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1. Identification and Characterisation of Cotton Boll Wall-Specific Gene Promoters for Future Transgenic Cotton Varieties

Author: Sharon J. Orford, Damien J. Lightfoot, and Jeremy N. Timmis
Subjects: Chalcone synthase, Genetics, Transformation (genetics), Reporter gene, biology, Transgene, In silico, biology.protein, Promoter, Plant Science, Genetically modified crops, Molecular Biology, Gene
Abstract: Current transgenic cotton varieties constitutively express transgenes encoding anti-pest proteins to protect against plant damage caused by insect attack. However, restricting the spatial expression of transgenes to the tissues in which their products are required is likely to improve crop performance and reduce environmental impacts. Therefore, we sought to identify native gene promoters that would restrict transgene expression to the boll wall of the cotton plant. Six abundant mRNAs that accumulated preferentially in the boll wall were identified, and the gene promoters of two of these mRNAs were identified, isolated and characterised. The promoters of a proline-rich protein gene (GhPRP3) and a chalcone synthase gene (GhCHS1) were demonstrated to drive boll wall-preferential expression of a reporter gene in a transient transformation system. In silico analyses of the GhPRP3 and GhCHS1 promoters identified numerous previously identified cis-acting regulatory elements (CAREs) as well as the presence of three novel shared CAREs. The identification and characterisation of these promoters provides an important step in the development of the next generation of transgenic plants.
Published: 2012
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2. Urinary bladder auto augmentation using INTEGRA® and SURGISIS®: an experimental model

Author: Saeed Ahmed, Jevon Gerath, J Orford, Andrew Barker, and Gera Parshotam Kumar
Subjects: medicine.medical_specialty, Urinary Bladder, Urology, urologic and male genital diseases, Statistics, Nonparametric, Postoperative Complications, Absorbable Implants, Intestine, Small, medicine, Animals, Sheep, Urinary bladder, Tissue Extracts, Experimental model, business.industry, Chondroitin Sulfates, General Medicine, Plastic Surgery Procedures, Elasticity, Surgery, medicine.anatomical_structure, Models, Animal, Pediatrics, Perinatology and Child Health, Female, Collagen, business, Omentum
Abstract: We present our experience with an experimental urinary bladder auto augmentation model using SURGISIS and INTEGRA (collagen layer) in comparison with seromuscular enterocystoplasty. The aim of the study was to evaluate the change in compliance and elasticity of the urinary bladder.Eighteen lambs were divided into three different groups. Auto augmentation was performed using the seromuscular layer of small bowel, SURGISIS or the collagen layer of INTEGRA. After 3 months of the initial procedure, the lambs were re-operated, the bladder compliance was measured and the urinary bladder was submitted for histological examination and assessment of elasticity. The lambs were euthanized.The postoperative period was uneventful in 17 lambs except for intestinal obstruction in one lamb from the seromuscular enterocystoplasty group. A statistically significant difference in compliance was observed with SURGISIS and the INTEGRA. Histologically, there was neovascularization in all the specimens from the SURGISIS and INTEGRA groups with the presence of fibrosis in the SURGISIS group. The INTEGRA group showed better elastic properties than the SURGISIS.Urinary bladder auto augmentation using the collagen layer of INTEGRA showed better functional and histological results when compared with SURGISIS and demucosalized enterocystoplasty in the present model.
Published: 2009
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3. Very high energy γ-ray observations of the binary PSR B1259–63/SS2883 around the 2007 Periastron

Author: A. A. Zdziarski, M. K. Daniel, Gavin Rowell, L. Venter, A. C. Clapson, M. C. Medina, T. J. L. McComb, Gilles Henri, Marek Sikora, W. Domainko, P. H. Tam, S. Rosier-Lees, P. Espigat, S. Schwemmer, Cameron B Rulten, Andrea Santangelo, Michal Dyrda, K. Katarzyński, M. Kerschhaggl, Michael Punch, Felix Aharonian, Guillaume Dubus, Jacek Niemiec, B. C. Raubenheimer, B. Giebels, A. R. Bazer-Bachi, F. Brun, O. Tibolla, A. Shalchi, D. Gerbig, M. Panter, J. L. Skilton, O. C. de Jager, S. Schwarzburg, D. Nedbal, M. Vivier, Karl Kosack, Christian Farnier, C. Stegmann, I. Jung, Stefan Wagner, Gisela Anton, Dieter Horns, Pierre Brun, Łukasz Stawarz, B. Rudak, Kathrin Egberts, G. Lamanna, B. Degrange, A. Cheesebrough, J. Dyks, Heinrich J. Völk, P. Vincent, I. D. Davids, Frank M. Rieger, D. Göring, David Maurin, S. Pita, V. Borrel, M. Tluczykont, Y. A. Gallant, Stefan Ohm, G. Coignet, J-F. Olive, Martin Ward, B. Behera, L. Rob, V. Sahakian, G. Vasileiadis, Rolf Bühler, Andreas Quirrenbach, J.-P. Tavernet, A. Hoffmann, J. F. Glicenstein, R. Kossakowski, F. M. Schöck, M. Paz Arribas, G. Heinzelmann, J. Bolmont, Ullrich Schwanke, M. Dalton, A. G. Akhperjanian, R. Steenkamp, G. Pedaletti, J.-P. Lenain, P. M. Chadwick, Francesca Volpe, B. Nicholas, Anna Szostek, F. Dubois, Konrad Bernlöhr, G. Superina, G. Pühlhofer, A. Fiasson, Timothé Boutelier, Emmanuel Moulin, Reinhard Schlickeiser, Hugh Dickinson, V. Marandon, Christo Venter, C. Jahn, U. F. Katz, A. Zech, A. Djannati-Ataï, M. Hauser, C. van Eldik, M. Holleran, M. Renaud, D. Hauser, D. Klochkov, Catherine Boisson, Rafal Moderski, Dimitrios Emmanoulopoulos, H. Sol, R. C. G. Chaves, S. M. Rayner, J. P. Vialle, P. Goret, Guy Pelletier, A. Förster, Martin Raue, S. Hoppe, A. Charbonnier, S. Heinz, L. O'c. Drury, M. Füßling, E. de Oña Wilhelmi, Sarah Kaufmann, L. Gérard, B. Glück, Nu. Komin, T. Bulik, Christoph Deil, T. Kneiske, I. Büsching, P.-O. Petrucci, L.-M. Chounet, Yvonne Becherini, D. Nekrassov, W. Kluźniak, A. Jacholkowska, G. Fontaine, S. J. Nolan, Jim Hinton, Dmitry Khangulyan, Thomas Lohse, Michał Ostrowski, K. J. Orford, J. Ripken, D. Keogh, Werner Hofmann, U. Barres de Almeida, F. Feinstein, Julien Masbou, Stefano Gabici, M. de Naurois, Alexandre Marcowith, O. Martineau-Huynh, B. Khélifi, G. Hermann, Regis Terrier, J. Ruppel, J. Brucker, D. Spangler, M. Naumann-Godo, F. Stinzing, A. Bochow, Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), APC - Astrophysique des Hautes Energies (APC - AHE), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), HESS, Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, and Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)
Subjects: [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], observational [methods], Flux, Astrophysics, 01 natural sciences, Spectral line, neutron [stars], Pulsar, 0103 physical sciences, Binary star, 010303 astronomy & astrophysics, Astroparticle physics, Physics, 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], binaries: general [stars], Gamma ray, observations [gamma rays], Astronomy, telescopes, Astronomy and Astrophysics, non-thermal [radiation mechanisms], Light curve, Neutron star, 13. Climate action, Space and Planetary Science
Abstract: Aims. This article presents very-high-energy (VHE; E > 100 GeV) data from the $\gamma$-ray binary PSR B1259-63 as taken during the years 2005, 2006 and before as well as shortly after the 2007 periastron passage. These data extend the knowledge of the lightcurve of this object to all phases of the 3.4 year binary orbit. The lightcurve constrains physical mechanisms present in this TeV source. Methods. Observations of VHE $\gamma$-rays with the HESS telescope array using the Imaging Atmospheric Cherenkov Technique were performed. The HESS instrument features an angular resolution of < 0.1° and an energy resolution of < 20%. Gamma-ray events in an energy range of 0.5-70 TeV were recorded. From these data, energy spectra and lightcurve with a monthly time sampling were extracted. Results. VHE $\gamma$-ray emission from PSR B1259-63 was detected with an overall significance of 9.5 standard deviations using 55h of exposure, obtained from April to August 2007. The monthly flux of $\gamma$-rays during the observation period was measured, yielding VHE lightcurve data for the early pre-periastron phase of the system for the first time. No spectral variability was found on timescales of months. The spectrum is described by a power law with a photon index of $\Gamma$ = 2.8 $\pm$ 0.2stat $\pm$ 0.2sys and flux normalisation $\Phi_{0}$ = (1.1 $\pm$ 0.1stat $\pm$ 0.2sys) $\times$ 10-12 TeV-1 cm-2 s-1. PSR B1259-63 was also monitored in 2005 and 2006, far from periastron passage, comprising 8.9 h and 7.5 h of exposure, respectively. No significant excess of $\gamma$-rays is seen in those observations. Conclusions. PSR B1259-63 has been re-confirmed as a variable TeV $\gamma$-ray emitter. The firm detection of VHE photons emitted at a true anomaly $\theta$$\approx$-0.35 of the pulsar orbit, i.e. already ~50 days prior to the periastron passage, disfavors the stellar disc target scenario as a primary emission mechanism, based on current knowledge about the companion star's disc inclination, extension, and density profile. Results. VHE $\gamma$-ray emission from PSR B1259-63 was detected with an overall significance of 9.5 standard deviations using 55h of exposure, obtained from April to August 2007. The monthly flux of $\gamma$-rays during the observation period was measured, yielding VHE lightcurve data for the early pre-periastron phase of the system for the first time. No spectral variability was found on timescales of months. The spectrum is described by a power law with a photon index of $\Gamma$ = 2.8 $\pm$ 0.2stat $\pm$ 0.2sys and flux normalisation $\Phi_{0}$ = (1.1 $\pm$ 0.1stat $\pm$ 0.2sys) $\times$ 10-12 TeV-1 cm-2 s-1. PSR B1259-63 was also monitored in 2005 and 2006, far from periastron passage, comprising 8.9 h and 7.5 h of exposure, respectively. No significant excess of $\gamma$-rays is seen in those observations. Conclusions. PSR B1259-63 has been re-confirmed as a variable TeV $\gamma$-ray emitter. The firm detection of VHE photons emitted at a true anomaly $\theta$$\approx$-0.35 of the pulsar orbit, i.e. already ~50 days prior to the periastron passage, disfavors the stellar disc target scenario as a primary emission mechanism, based on current knowledge about the companion star's disc inclination, extension, and density profile.
Published: 2009
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4. Simultaneous HESS and Chandra observations of Sagitarius A$^{\star}$ during an X-ray flare

Author: F. Aharonian, A. G. Akhperjanian, U. Barres de Almeida, A. R. Bazer-Bachi, Y. Becherini, B. Behera, W. Benbow, K. Bernlöhr, C. Boisson, A. Bochow, V. Borrel, I. Braun, E. Brion, J. Brucker, P. Brun, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, S. Carrigan, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L.-M. Chounet, A. C. Clapson, G. Coignet, M. Dalton, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, M. Füßling, S. Gabici, Y. A. Gallant, L. Gérard, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, C. Hadjichristidis, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, I. Jung, K. Katarzyński, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khélifi, D. Keogh, Nu. Komin, K. Kosack, G. Lamanna, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, M. C. Medina, R. Moderski, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Oña Wilhelmi, K. J. Orford, J. L. Osborne, M. Ostrowski, M. Panter, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. Rudak, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, J. L. Skilton, H. Sol, D. Spangler, Ł. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, C. van Eldik, G. Vasileiadis, C. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), HESS, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), 10859748 - Holleran, Mathew, 12006653 - Venter, Christo, 10179240 - Raubenheimer, Barend Christoffel, 13235176 - Büsching, Ingo, 10065857 - De Jager, Ocker Cornelis, Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris
Subjects: [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Event horizon, Astrophysics::High Energy Astrophysical Phenomena, Population, FOS: Physical sciences, Flux, Astrophysics, gamma-rays:observations, 01 natural sciences, law.invention, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Coincident, law, 0103 physical sciences, education, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, individuals: Sgr A* [X-rays], Supermassive black hole, education.field_of_study, 010308 nuclear & particles physics, Astrophysics (astro-ph), observations [gamma rays], Astronomy and Astrophysics, X-rays:individual sources:Sgr A, Particle acceleration, Sagittarius A, Space and Planetary Science, individuals: Sgr $A^{\star }$ [X-rays], Flare
Abstract: The rapidly varying (~10 minute timescale) non-thermal X-ray emission observed from Sgr A* implies that particle acceleration is occuring close to the event horizon of the supermassive black hole. The TeV gamma-ray source HESS J1745-290 is coincident with Sgr A* and may be closely related to its X-ray emission. Simultaneous X-ray and TeV observations are required to elucidate the relationship between these objects. We report on joint H.E.S.S./Chandra observations performed in July 2005, during which an X-ray flare was detected. Despite a factor of 9 increase in the X-ray flux of Sgr A*, no evidence is found for an increase in the TeV gamma-ray flux from this region. We find that an increase in the gamma-ray flux of a factor of 2 or greater can be excluded at a confidence level of 99%. This finding disfavours scenarios in which the keV and TeV emission are associated with the same population of accelerated particles and in which the bulk of the gamma-ray emission is produced within ~10^{14} cm (~100 R_S) of the supermassive black hole., 5 pages, 2 figures
Published: 2008
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5. Evidence for alternative splicing of MADS-box transcripts in developing cotton fibre cells

Author: Katharine M. Malone, Sharon J. Orford, Jeremy N. Timmis, and Damien J. Lightfoot
Subjects: DNA, Complementary, animal structures, Molecular Sequence Data, Gene Expression, MADS Domain Proteins, Biology, Genes, Plant, Exon, Complementary DNA, Gene expression, Genetics, Amino Acid Sequence, RNA, Messenger, Cloning, Molecular, Molecular Biology, Gene, Phylogeny, MADS-box, DNA Primers, Plant Proteins, Gossypium, Base Sequence, Sequence Homology, Amino Acid, Agamous, Alternative splicing, Intron, General Medicine, Alternative Splicing, RNA, Plant
Abstract: The MADS-box family of genes encodes transcription factors that have widely ranging roles in diverse aspects of plant development. In this study, four cotton MADS-box cDNA clones of the type II (MIKC) class were isolated, with phylogenetic analysis indicating that the cotton sequences are of the AGAMOUS subclass. The corresponding transcripts were detected in developing cotton fibre cells as well as in whole ovule and flower tissue, with differential expression in stems, leaves and roots. Reverse transcription PCR showed extensive alternative splicing in one of the reactions, and 11 mRNAs of different intron/exon composition and length were characterised. Sequence differences between the transcripts indicated that they could not be derived from the same pre-mRNA and that the sequenced transcript pool was derived from two distinct MADS-box genes. Several of the alternatively spliced transcripts potentially encoded proteins with altered K-domains and/or C-terminal regions and the variant proteins may have altered cellular roles. This work is the first that describes MADS-box gene expression in elongating cotton fibres and adds to a growing body of evidence for the prevalence of alternative splicing in the expression of MADS-box and other genes.
Published: 2007
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6. Incorporation of Integra® in tissue defects: a pilot study in the rat model

Author: Manasvi Upadhyaya, Nicholas Smith, J Orford, Ian Gollow, and Andrew Barker
Subjects: medicine.medical_specialty, medicine.medical_treatment, Diaphragm, Urinary Bladder, Neovascularization, Physiologic, Diaphragmatic breathing, Pilot Projects, Abdominal cavity, Abdominal wall, Fibrosis, medicine, Animals, Rats, Wistar, Urinary bladder, Debridement, business.industry, Abdominal Wall, Chondroitin Sulfates, General Medicine, medicine.disease, Rats, Diaphragm (structural system), Surgery, medicine.anatomical_structure, Pediatrics, Perinatology and Child Health, Collagen, Implant, business
Abstract: Integra® has been shown to be very useful in accelerating the growth of neodermis. It has found extensive use in case of burns as a primary dressing immediately after a burn, after release of contractures and following scar revision. It has been used to achieve cover after the debridement of extensive infective processes involving the skin. Encouraged by these results we have assessed the application of Integra® to augment and/or patch defects of the urinary bladder, diaphragm and the abdominal wall in the rat model. This was a pilot study and involved the incorporation of Integra® in the diaphragm, the urinary bladder (extramucosal) and the muscle layer of the abdominal wall. Eight adult Wistar rats were given general anaesthesia and Integra® was implanted with absorbable sutures at the sites mentioned. The omentum was hitched to the collagen matrix surface to revascularise the graft. The silicone was left in situ. The operative period was covered with antibiotics. The anaesthesia was then reversed. Postoperatively the rats were given analgesia and feeds started immediately. The rats were sacrificed after 3 weeks. The abdominal cavity was examined for adhesions. The Integra® implant along with adjacent tissue was harvested and examined histologically. There were no visible intra-abdominal adhesions. The histology revealed good degree of neovascularisation and fibrosis in and adjacent to the implant. This was comparable to the changes seen in the skin. This pilot study has shown that implanting Integra® invokes a similar response in deeper tissues and it can develop neovascularisation from the omentum. Hence, this could find some application in treating congenital conditions such as diaphragmatic hernias, abdominal wall defects and for bladders requiring augmentation. Our initial results are quite encouraging and we feel that this field should be further explored.
Published: 2007
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7. Discovery of the two 'wings' of the Kookaburra complex in VHE γ-rays with HESS

Author: F. Aharonian, A. G. Akhperjanian, A. R. Bazer-Bachi, M. Beilicke, W. Benbow, D. Berge, K. Bernlöhr, C. Boisson, O. Bolz, V. Borrel, I. Braun, A. M. Brown, R. Bühler, I. Büsching, S. Carrigan, P. M. Chadwick, L.-M. Chounet, R. Cornils, L. Costamante, B. Degrange, H. J. Dickinson, A. Djannati-Ataï, L. O'C. Drury, G. Dubus, K. Egberts, D. Emmanoulopoulos, P. Espigat, F. Feinstein, E. Ferrero, A. Fiasson, G. Fontaine, S. Funk, M. Füßling, Y. A. Gallant, B. Giebels, J. F. Glicenstein, P. Goret, C. Hadjichristidis, D. Hauser, M. Hauser, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, D. Horns, A. Jacholkowska, O. C. de Jager, E. Kendziorra, B. Khélifi, Nu. Komin, A. Konopelko, K. Kosack, I. J. Latham, R. Le Gallou, A. Lemière, M. Lemoine-Goumard, T. Lohse, J. M. Martin, O. Martineau-Huynh, A. Marcowith, C. Masterson, G. Maurin, T. J. L. McComb, M. de Naurois, D. Nedbal, S. J. Nolan, A. Noutsos, K. J. Orford, J. L. Osborne, M. Ouchrif, M. Panter, G. Pelletier, S. Pita, G. Pühlhofer, M. Punch, B. C. Raubenheimer, M. Raue, S. M. Rayner, A. Reimer, O. Reimer, J. Ripken, L. Rob, L. Rolland, G. Rowell, V. Sahakian, A. Santangelo, L. Saugé, S. Schlenker, R. Schlickeiser, R. Schröder, U. Schwanke, S. Schwarzburg, A. Shalchi, H. Sol, D. Spangler, F. Spanier, R. Steenkamp, C. Stegmann, G. Superina, J.-P. Tavernet, R. Terrier, C. G. Théoret, M. Tluczykont, C. van Eldik, G. Vasileiadis, C. Venter, P. Vincent, H. J. Völk, S. J. Wagner, and M. Ward
Subjects: Point spread function, Physics, Photon, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Cosmic microwave background, Gamma ray, Astronomy and Astrophysics, Radius, Astrophysics, 01 natural sciences, Pulsar, 13. Climate action, Space and Planetary Science, 0103 physical sciences, Light emission, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Cherenkov radiation
Abstract: Aims. Search for Very High Energy gamma-ray emission in the Kookaburra complex through observations with the H.E.S.S. array. Methods. Stereoscopic imaging of Cherenkov light emission of the gamma-ray showers in the atmosphere is used for the reconstruction and selection of the events to search for gamma-ray signals. Their spectrum is derived by a forward-folding maximum likelihood fit. Results. Two extended gamma-ray sources with an angular (68%) radius of 3.3-3.4' are discovered at high (>13sigma) statistical significance: HESS J1420-607 and HESS J1418-609. They exhibit a flux above 1 TeV of (2.97+/-0.18stat +/-0.60sys)x10-12 and (2.17+/-0.17stat +/-0.43sys)x10-12 cm-2 s-1, respectively, and similar hard photon indices ~2.2. Multi-wavelength comparisons show spatial coincidence with the wings of the Kookaburra. Two pulsar wind nebulae candidates, K3/PSR J1420-6048 and the Rabbit, lie on the edge of the H.E.S.S. sources. Conclusions. The two new sources confirm the non-thermal nature of at least parts of the two radio wings which overlap with the gamma-ray emission and establish their connection with the two X-ray pulsar wind nebulae candidates. Given the large point spread function of EGRET, the unidentified source(s) 3EG J1420-6038/GeV J1417-6100 could possibly be related to either or both H.E.S.S. sources. The most likely explanation for the Very High Energy gamma-rays discovered by H.E.S.S. is inverse Compton emission of accelerated electrons on the Cosmic Microwave Background near the two candidate pulsar wind nebulae, K3/PSR J1420-6048 and the Rabbit. Two scenarios which could lead to the observed large (~10 pc) offset-nebula type morphologies are briefly discussed.
Published: 2006
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8. Observations of Mkn 421 in 2004 with HESS at large zenith angles

Author: Aharonian, F., G. Akhperjanian, A., Aye, K.-M., R. Bazer-Bachi, A., Beilicke, M., Benbow, W., Berge, D., Berghaus, P., Bernlöhr, K., Boisson, C., Bolz, O., Braun, I., Breitling, F., M. Brown, A., Bussons Gordo, J., M. Chadwick, P., Chounet, L.-M., Cornils, R., Costamante, L., Degrange, B., Djannati-Ataï, A., O'C. Drury, L., Dubus, G., Emmanoulopoulos, D., Espigat, P., Feinstein, F., Fleury, P., Fontaine, G., Fuchs, Y., Funk, S., Gallant, Y.A., Giebels, B., Gillessen, S., F. Glicenstein, J., Goret, P., Hadjichristidis, C., Hauser, M., Heinzelmann, G., Henri, G., Hermann, G., A. Hinton, J., Hofmann, W., Holleran, M., Horns, D., C. De Jager, O., Khélifi, B., Komin, Nu., Konopelko, A., J. Latham, I., Le Gallou, R., Lemière, A., Lemoine, M., Leroy, N., Lohse, T., Marcowith, A., Masterson, C., J. L. Mccomb, T., De Naurois, M., J. Nolan, S., Noutsos, A., J. Orford, K., L. Osborne, J., Ouchrif, M., Panter, M., Pelletier, G., Pita, S., Pühlhofer, G., Punch, M., C. Raubenheimer, B., Raue, M., Raux, J., M. Rayner, S., Redondo, I., Reimer, A., Reimer, O., Ripken, J., Rob, L., Rolland, L., Rowell, G., Sahakian, V., Saugé, L., Schlenker, S., Schlickeiser, R., Schuster, C., Schwanke, U., Siewert, M., Sol, H., Steenkamp, R., Stegmann, C., Tavernet, J.-P., Terrier, R., Théoret, C.G., Tluczykont, M., Vasileiadis, G., Venter, C., Vincent, P., J. Völk, H., J. Wagner, S., AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), HESS, Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC)
Subjects: Physics, Photon, Spectral shape analysis, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), FOS: Physical sciences, galaxies: individual: Mkn 421, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, Standard deviation, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Amplitude, Flux (metallurgy), Space and Planetary Science, 0103 physical sciences, Cutoff, High Energy Stereoscopic System, 010303 astronomy & astrophysics, Zenith
Abstract: Mkn 421 was observed during a high flux state for nine nights in April and May 2004 with the fully operational High Energy Stereoscopic System (H.E.S.S.) in Namibia. The observations were carried out at zenith angles of 60$^\circ$--65$^\circ$, which result in an average energy threshold of 1.5 TeV and a collection area reaching 2~km$^2$ at 10~TeV. Roughly 7000 photons from Mkn~421 were accumulated with an average gamma-ray rate of 8 photons/min. The overall significance of the detection exceeds 100 standard deviations. The light-curve of integrated fluxes above 2~TeV shows changes of the diurnal flux up to a factor of 4.3. For nights of high flux, intra-night variability is detected with a decay time of less than 1 hour. The time averaged energy spectrum is curved and is well described by a power-law with a photon index $\egamm$ and an exponential cutoff at $\ecut$~TeV and an average integral flux above 2~TeV of 3 Crab flux units. Significant variations of the spectral shape are detected with a spectral hardening as the flux increases. Contemporaneous multi-wavelength observations at lower energies (X-rays and gamma-rays above $\approx 300$~GeV) indicate smaller relative variability amplitudes than seen above 2~TeV during high flux state observed in April 2004., Comment: 5 pages, 4 figures, published in A&A
Published: 2005
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9. Recent observations of VHE gamma rays from Cygnus X-3

Author: S. M. Rayner, D J Orford, K. E. Turver, V. G. Mannings, A. Carraminana, P. J. Edwards, P. M. Chadwick, K. T. S. Brazier, S.M. Bradbury, K. J. Orford, C. C. G. Bowden, Nigel Dipper, E. W. Lincoln, and T. J. L. McComb
Subjects: Physics, Telescope, Nuclear and High Energy Physics, High energy, Pulsar, law, Gamma ray, Northern Hemisphere, Astronomy, Astrophysics, Southern Hemisphere, Zenith, law.invention
Abstract: The authors' observations of Cygnus X-3 in 1981-88 have suggested that sporadic 12.6 ms pulsed very high energy gamma rays are produced at or near the maximum (phase 0.6) in the 4.8 h X-ray cycle. Cygnus X-3 was observed with the Durham University Mark IV Northern Hemisphere gamma-ray telescope in 1989, shortly after two radio outbursts were detected from the object. An analysis of these data suggests that 12.6 ms pulsar emission may be observed at a phase in the 4.8 h cycle some 1000 s before their prediction from previous measurements. This is in agreement with measurements made at Woomera by the University of Adelaide. More recent observations using the Mark III Southern Hemisphere telescope at large zenith angles have not provided any further evidence for pulsar activity.
Published: 1992
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10. Characterisation of six α-expansin genes in Gossypium hirsutum (upland cotton)

Author: Harmer Se, Sharon J. Orford, and Jeremy N. Timmis
Subjects: Transcription, Genetic, Molecular Sequence Data, Biology, Genes, Plant, Gossypium hirsutum, Cell wall, Expansin, Plant Growth Regulators, Gene Expression Regulation, Plant, Botany, Genetics, Genomic library, Amino Acid Sequence, Ovule, Molecular Biology, Gene, Phylogeny, Plant Proteins, Gossypium, Messenger RNA, Epidermis (botany), Reverse Transcriptase Polymerase Chain Reaction, Exons, General Medicine, Introns, Cell biology, Multigene Family, Sequence Alignment
Abstract: A genomic library screen and PCR-based strategies were employed to isolate six genes with sequence similarity to a cotton fibre-specific mRNA encoding an alpha-expansin. alpha-Expansins are cell wall proteins that facilitate cell wall extension by disruption of non-covalent bonds between wall components. The characterisation and expression analysis of these six novel genes ( GhExp1-GhExp6) is described. Four of them ( GhExp3- GhExp6) are expressed within multiple tissues of the cotton plant and two ( GhExp1 and GhExp2) give rise to transcripts that are specific to the developing cotton fibre. GhExp1 transcripts are highly abundant in the fibre, while transcripts for GhExp2 are detected at a low level. Cotton fibres are highly elongated cells of the ovule epidermis, and we envisage that GhExp1 may play an important role in cell wall extension during development.
Published: 2002
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11. Very high energy gamma-rays from Centaurus X-3: Indications and implications

Author: A. M. Atoyan, K.-M. Aye, P. M. Chadwick, M. K. Daniel, K. Lyons, T. J. L. McComb, J. M. McKenny, S. J. Nolan, K. J. Orford, J. L. Osborne, and S. M. Rayner
Subjects: Acceleration of particles, Observation, Astrophysics::High Energy Astrophysical Phenomena, Non-thermal, FOS: Physical sciences, Binary number, Astrophysics, Compact star, law.invention, Telescope, Acceleration, symbols.namesake, Pulsar, law, Radiation mechanisms, Theory, Rayleigh scattering, Physics, Astrophysics (astro-ph), Gamma ray, Astronomy and Astrophysics, CEN x-3, Stars, Neutron star, Space and Planetary Science, symbols, Gamma-rays
Abstract: A timing analysis of VHE gamma-ray observations of Cen X-3 taken with the University of Durham Mark 6 telescope was performed, using both Rayleigh and Bayesian statistics. Data from only 1 observation produced evidence for periodicity, in a 'soft' cut data set, with an overall chance probability, 18 pages, 10 figures to be published in Astronomy and Astrophysics
Published: 2002
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12. The psychological impact of recurrent miscarriage, and the role of counselling at a pre-pregnancy counselling clinic

Author: M. Kilby, J. Orford, R. Kirchmeier, G. Jongman, and E. Rowsell
Subjects: medicine.medical_specialty, Pre pregnancy, Avoidance coping, Obstetrics and Gynecology, medicine.disease, Hospital Anxiety and Depression Scale, Distress, Reproductive Medicine, Psychological adaptation, Pediatrics, Perinatology and Child Health, Recurrent miscarriage, medicine, Anxiety, medicine.symptom, Psychiatry, Psychology, General Psychology, Event scale
Abstract: The current study investigates the psychological impact of recurrent miscarriage, and ways in which intervention at a pre-pregnancy counselling clinic (PPCC) influences psychological adaptation. Thirty-seven women who had been referred to the PPCC following two or more miscarriages completed questionnaires at three time points. This sample was found to have particularly high levels of anxiety, as well as intrusive and avoidant distress (as measured by the Hospital Anxiety and Depression Scale and the Impact of Event Scale). It was hypothesised that levels of psychological distress would remain constant over the baseline period, and then decrease significantly following intervention at the PPCC. Although there was a reduction in scores over time, only the pattern of change for Impact of Event Scale avoidance provided support for this hypothesis. There was a reduction in both avoidance coping and active coping strategies over time, but these changes could not be attributed to the intervention. No evidence w...
Published: 2001
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13. Very High Energy Gamma Rays from Young Pulsars and Supernova Remnants in the Southern Hemisphere

Author: K. E. Turver, J. L. Osborne, P. M. Chadwick, T. J. L. McComb, K. Lyons, S. M. Rayner, K. J. Orford, and S. E. Shaw
Subjects: Physics, Astrophysics::High Energy Astrophysical Phenomena, Pulsar planet, Gamma ray, Astronomy, Astronomy and Astrophysics, Astrophysics, Vela, Supernova, Neutron star, Pulsar, Space and Planetary Science, Millisecond pulsar, Southern Hemisphere, Astrophysics::Galaxy Astrophysics
Abstract: Observations have been made with the University of Durham Mark 6 telescope of a number of southern hemisphere supernova remnants and young pulsars (Vela pulsar, PSR B1055-52, PSR J1105-6107, PSR J0537-6910, and PSR B0540-69). No very high energy gamma-ray emission, either steady or pulsed, has been detected from these objects. The implications of these results for theories of high-energy gamma-ray production in plerions and young pulsars are discussed.
Published: 2000
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14. The analysis of cosmic ray data

Author: K. J. Orford
Subjects: Physics, Nuclear and High Energy Physics, Astrophysics::High Energy Astrophysical Phenomena, Bayesian probability, Cosmic ray, Astrophysics
Abstract: Reviews statistical methods for 1- and 2-dimensional analysis of cosmic ray data including recent Bayesian analyses.
Published: 2000
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15. The correction of atmospheric Cerenkov images for the effect of the geomagnetic field

Author: S. M. Rayner, K. J. Orford, J. L. Osborne, S. E. Shaw, P. M. Chadwick, T. J. L. McComb, K. E. Turver, and K. Lyons
Subjects: Physics, Nuclear and High Energy Physics, High energy, Orientation (computer vision), business.industry, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Instrumentation and Methods for Astrophysics, Gamma ray, Cosmic ray, Astrophysics, First order, law.invention, Telescope, Optics, Earth's magnetic field, law, Sensitivity (control systems), business
Abstract: Imaging atmospheric Cerenkov telescopes use the differences in shape and orientation of the images of development of cascades to distinguish between very high energy gamma rays and the cosmic ray background. We have previously shown that these images may be distorted by the effects of the geomagnetic field, which decreases the sensitivity of a telescope. In this paper we propose an analysis technique which corrects for (in first order) the effects of the geomagnetic field on the orientation of gamma ray images. Applying this technique to observations of gamma ray sources, we demonstrate that these corrections reduce the effect of the geomagnetic field and improve the sensitivity of the University of Durham Mark 6 telescope.
Published: 1999
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16. A Search for Very High Energy Gamma Rays from Active Galactic Nuclei Visible from the Southern Hemisphere

Author: P. M. Chadwick, K. E. Turver, K. J. Orford, T. J. L. McComb, S. M. Rayner, S. E. Shaw, J. L. Osborne, and K. Lyons
Subjects: Physics, High energy, Active galactic nucleus, Space and Planetary Science, Gamma ray, Astronomy and Astrophysics, Astrophysics, Southern Hemisphere, Fermi Gamma-ray Space Telescope
Abstract: Observations have been made, using the University of Durham Mark 6 gamma ray telescope, of the very high energy gamma ray emission from a number of active galactic nuclei visible from the Southern hemisphere. Limits are presented to the VHE gamma ray emission from 1ES 0323+022, PKS 0829+046, 1ES 1101--232, Cen A, PKS 1514-24, RXJ 10578-275, and 1ES 2316-423, both for steady long-term emission and for outbursts of emission on timescales of 1 day.
Published: 1999
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17. Observations of TeV gamma rays from Markarian 501 at large zenith angles

Author: S. E. Shaw, P. M. Chadwick, K. E. Turver, J. L. Osborne, S. M. Rayner, K. J. Orford, T. J. L. McComb, and K. Lyons
Subjects: Physics, Nuclear and High Energy Physics, Range (particle radiation), Astrophysics (astro-ph), Gamma ray, FOS: Physical sciences, Astrophysics, law.invention, Telescope, law, Imaging technique, Blazar, Zenith, Flare
Abstract: TeV gamma rays from the blazar Markarian 501 have been detected with the University of Durham Mark 6 atmospheric Cerenkov telescope using the imaging technique at large zenith angles. Observations were made at zenith angles in the range 70 - 73 deg during 1997 July and August when Markarian 501 was undergoing a prolonged and strong flare., 7 pages, 2 figures, accepted for publication in J. Phys. G.: Nucl. Part. Phys
Published: 1999
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18. PKS 2155-304 - a source of VHE γ-rays

Author: P. M. Chadwick, T. J. L. McComb, K. Lyons, J. L. Osborne, S. McQueen, K. E. Turver, S. M. Rayner, S. E. Shaw, G. J. Wieczorek, and K. J. Orford
Subjects: Physics, PKS 2155-304, High energy, Gamma ray, Astronomy and Astrophysics, Astrophysics, Fermi Gamma-ray Space Telescope
Abstract: The close X-ray selected BL Lac PKS 2155--304 has been observed using the University of Durham Mark 6 very high energy (VHE) gamma ray telescope during 1996 September/October/November and 1997 October/November. VHE gamma rays with energy > 300 GeV were detected with a time-averaged integral flux of (4.2 +/- 0.7 (stat) +/- 2.0 (sys)) x 10^-11 cm^-2 s^-1. There is evidence for VHE gamma ray emission during our observations in 1996 September and 1997 October/November. The strongest emission was detected in 1997 November, when the object was producing the largest flux ever recorded in high-energy X-rays and was detected in > 100 MeV gamma-rays. The VHE and X-ray fluxes are correlated.
Published: 1999
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19. Characterisation of a cotton gene expressed late in fibre cell elongation

Author: Jeremy N. Timmis, N. S. Olesnicky, Thomas J. Carney, and Sharon J. Orford
Subjects: Genetics, Expressed sequence tag, cDNA library, Nucleic acid sequence, General Medicine, Biology, Genome, Molecular biology, Open reading frame, Fiber cell, Complementary DNA, Agronomy and Crop Science, Gene, Biotechnology
Abstract: Full-length transcripts corresponding to a cotton fibre-specific cDNA, pFS18, were isolated by cDNA library screening and 5′-RACE. The cDNA sequences contained a short open reading frame of only 71 amino acids which showed a limited amount of similarity to lipid transfer proteins. Southern analysis revealed the presence of 4–6 related genes in the tetraploid (AD) G. hirsutum genome, one of which, FS18A, was isolated and shown to contain a short open reading frame which originated from the ancestral A diploid genome. Sequence differences between the gene and the full-length pFS18 cDNA, together with the finding that pFS18 is transcribed from the D diploid genome, demonstrated that FS18A does not encode the abundant fibre-specific transcripts represented by pFS18. However, RT-PCR experiments showed that both pFS18 and FS18A-derived transcripts are present in fibre cells at elevated levels compared with other cotton tissues, with the accumulation of transcripts from both genes being greatest during and after the onset of secondary wall synthesis.
Published: 1999
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20. Dose response relationship between adriamycin and birth defects in a rat model of VATER association

Author: Daniel T. Cass and J Orford
Subjects: medicine.medical_specialty, Gastroenterology, Rats, Sprague-Dawley, Random Allocation, Internal medicine, medicine, Animals, Humans, Abnormalities, Multiple, Esophagus, Esophageal Atresia, Fetus, Dose-Response Relationship, Drug, Esophageal disease, business.industry, Abnormalities, Drug-Induced, Reproducibility of Results, General Medicine, medicine.disease, Rats, Dose–response relationship, medicine.anatomical_structure, Endocrinology, Doxorubicin, Atresia, Pediatrics, Perinatology and Child Health, Toxicity, Gestation, Female, Surgery, business, Kidney disease
Abstract: The aim of this study was to reproduce the animal model of esophageal atresia and the VATER association. The purpose was a dose response analysis of Adriamycin teratogenicity in the rat and comparison of these anomalies with the human VATER association.Twenty time-mated Sprague-Dawley rats received intraperitoneal Adriamycin (dose range, 0 to 2.5 mg/kg/d) for 4 consecutive gestational days E6 to E9. The embryos were harvested on day E21, inspected, weighed, and dissected with a binocular dissecting microscope. Statistical analysis was performed with exact chi2.Threshold doses of 1.25 and 1.5 mg/kg/d Adriamycin produced renal and gastrointestinal anomalies, respectively (exact chi2, P.00001). In doses below 1.25 mg/kg/d Adriamycin, no anomalies were seen, and in above-threshold doses, the frequency of anomalies rose sharply as the dose increased. At 2.25 mg/kg/d of Adriamycin all embryos were abnormal, and Adriamycin at 2.5 mg/kg/d led to resorption of all embryos.Adriamycin induced esophageal atresia, and VATER in the rat is a reproducible model that has many similarities to the VATER anomalies in the human. There is a relationship between dose and the frequency as well as severity of anomalies. Further studies of this model are likely to provide information relevant to the understanding of this human congenital disease.
Published: 1999
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21. Very High Energy Gamma Rays from PKS 2155−304

Author: S. M. Rayner, P. M. Chadwick, J. L. Osborne, K. E. Turver, T. J. L. McComb, K. Lyons, K. J. Orford, S. E. Shaw, and G. J. Wieczorek
Subjects: Physics, PKS 2155-304, Telescope, High energy, Space and Planetary Science, law, Gamma ray, Astronomy and Astrophysics, Astrophysics, law.invention
Abstract: The close X-ray-selected BL Lac PKS 2155-304 has been observed using the University of Durham Mark 6 very high energy (VHE) gamma-ray telescope during 1996 September/October/November and 1997 October/November. VHE gamma rays with energy more than 300 GeV were detected from this object with a time-averaged integral flux of (4.2±0.7stat±2.0sys)×10−11 cm-2 s-1. There is evidence for VHE gamma-ray emission during our observations in 1996 September and 1997 October/November, with the strongest emission being detected in 1997 November, when the object was producing the largest flux ever recorded in high-energy X-rays and it was detected as a source of gamma rays of energy greater than 100 MeV. The VHE and X-ray fluxes show evidence of a correlation.
Published: 1999
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22. [Untitled]

Author: K. J. Orford, T. R. Kendall, K. Tindale, S. E. Hilton, S. P. Tummey, Nigel Dipper, M. D. Roberts, I. D. Roberts, J. Holder, M. Robertshaw, J. E. Dickinson, C. M. Moore, M. R. Dickinson, S. E. Shaw, W. Hogg, P. Cottle, P. Armstrong, T. J. L. McComb, K. E. Turver, S. M. Rayner, and P. M. Chadwick
Subjects: Physics, Astrophysics::High Energy Astrophysical Phenomena, Hadron, Astrophysics::Instrumentation and Methods for Astrophysics, Gamma ray, Astronomy, Astronomy and Astrophysics, Gamma-ray astronomy, law.invention, Telescope, Space and Planetary Science, law, High Energy Physics::Experiment, Astrophysics::Galaxy Astrophysics, Fermi Gamma-ray Space Telescope
Abstract: The design, construction and operation of the University of Durham ground-based gamma ray telescope is discussed. The telescope has been designed to detect gamma rays in the ≤ 200 GeV region and to achieve good discrimination between gamma ray and hadron initiated showers in the higher energy region (≳ 300 GeV). The telescope was commissioned in 1995 and a description of its design and operation is presented, together with a verification of the telescope's performance.
Published: 1999
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23. Abundant mRNAs specific to the developing cotton fibre

Author: Jeremy N. Timmis and Sharon J. Orford
Subjects: education.field_of_study, Sequence analysis, cDNA library, Population, Nucleic acid sequence, General Medicine, Biology, Molecular biology, Complementary DNA, Gene expression, Genetics, Nucleic acid, education, Agronomy and Crop Science, Gene, Biotechnology
Abstract: Five fibre-specific cDNA clones were isolated by differential screening of a cDNA library from cotton fibres, a developmentally synchronous population of non-dividing cells. The genes corresponding to these cDNAs were expressed preferentially in fibre cells and exhibited differing patterns of temporal expression during fibre development. One cDNA encoded a lipid transfer protein (LTP), and a second encoded a member of a group of well-characterised proline-rich proteins (PRP) from plants. The presence of signal peptide-encoding sequences suggests that both the LTP and the PRP are targeted to the extracellular matrix of the fibre, and a role is envisaged for each in cell elongation. Sequence analysis showed that a third clone was similar to a previously reported fibre-specific sequence of unknown function, whilst the remaining two cDNA clones showed no sequence similarity to previously reported plant nucleic acids.
Published: 1997
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24. Power, Powerlessness and Addiction

Author: J Orford
Abstract: Addiction exercises enormous power over all those who are touched by it. This book argues that power and powerlessness have been neglected in addiction studies and that they are a unifying theme that brings together different areas of research from the field including the disempowering nature of addiction; effects on family, community and the workplace; epidemiological and ethnographic work; studies of the legal and illegal supply; and theories of treatment and change. Examples of alcohol, drug and gambling addiction are used to discuss the evidence that addiction is most disempowering where social resources to resist it are weakest; the ways in which the dominant discourses about addictive behaviour encourage the attributing of responsibility for addiction to individuals and divert attention from the powerful who benefit from addiction; and the ways in which the voices of those whose interests are least well-served by addiction are silenced.
Published: 2013
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25. Elimination of red noise in pulsar searches

Author: K. J. Orford
Subjects: Physics, Pulsar, Colors of noise, Epoch (reference date), Astrophysics::High Energy Astrophysical Phenomena, Probability distribution, Astronomy and Astrophysics, Folding (DSP implementation), Astrophysics, Statistical physics, Very high energy gamma ray astronomy, Statistic, Statistical hypothesis testing
Abstract: The Rayleigh test has become a standard statistical test used in Very High Energy Gamma Ray Astronomy for searching for evidence of periodic gamma-ray emission. This is because it is easy to calculate, robust in use, and involves no arbitrary choice of parameter, unlike tests such as binned χ 2 (epoch folding). The validity of the test depends on the conditions of the application. In the case of long-period pulsars in data sets of a few hours duration one problem is red noise in which the theoretical probability distribution is incorrect at low periods. A re-formulation of the Rayleigh test statistic is supplied which removes this problem.
Published: 1996
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26. 10.9 Coastal Gravel Systems

Author: E. Anthony and J. Orford
Subjects: Geography, Berm, Process dynamics, Sediment, Geotechnical engineering, Geomorphology, Microscale chemistry, Beach morphodynamics
Abstract: Gravel beaches occupy a dominantly reflective morphodynamic domain, which has so far been relatively unexplored compared to their sandier counterparts. The dynamics of gravel beachfaces are considered in terms of step and berm evolution and their contribution to profile variation. Extensions of gravel profile types are considered in terms of relative gravel to sand volumes under the profile. The use of sediment assemblages and their association with both process dynamics and microscale morphology are presented via the concept of mosaics, which is considered to be the best approach toward better definition of microscale gravel beach morphodynamic regimes. There are limited morphodynamic links with gravel barrier evolution, though the mosaics as a statement of long-term barrier stability might be considered as a likelihood statement of potential future change.
Published: 2013
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27. A burst of pulsed VHE gamma rays from AE Aquarii

Author: M. R. Dickinson, M. D. Roberts, S. M. Rayner, P. M. Chadwick, I. D. Roberts, K. J. Orford, K. E. Turver, T. J. L. McComb, S. P. Tummey, J. E. Dickinson, J. Holder, and Nigel Dipper
Subjects: Physics, Brightness, Phase (waves), Gamma ray, Astronomy, Flux, Astronomy and Astrophysics, Cosmic ray, Astrophysics, Threshold energy, Luminosity, law.invention, Telescope, law
Abstract: We report the results of observations of AE Aquarii made on 25 occasions between July 1992 and October 1993 with the University of Durham very high energy (VHE) gamma-ray telescopes at Narrabri, N.S.W., Australia. The observations lasted for a total of 78 h and no persistent low-level pulsed emission was detected above an energy threshold of 350 GeV. However, an excess of pulsed VHE γ-rays was observed on 1993 October 11. The burst lasted for approximately 4200 s and occurred at phase 0.62–0.74 in the 9.88 h orbital cycle. The count rate excess was significant at the 0.99997 level and the periodicity was at the second harmonic of the 33 s period The hadron-induced background in the burst data has been suppressed by applying simple imaging techniques to those events recorded by an individual telescope and using trigonometric height of maximum analysis for the events recorded by two telescopes. These two independent results together provide evidence at a probability of chance occurrence of 10−7, after allowing for degrees of freedom, for the emission of a burst of pulsed γ-rays from AE Aquarii with threshold energy > 350 GeV, which show the characteristic features of γ-ray induced cascades. There is also some evidence to suggest that the brightness spectrum of Cerenkov events recorded during the burst is harder than that recorded in a sample of the background. The flux during the burst was approximately 4% of the total cosmic ray background at E> 350 GeV, corresponding to a peak pulsed luminosity of 1032 erg s−1
Published: 1995
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28. Bleomycin therapy for cystic hygroma

Author: J Murphy, Andrew Barker, S Thonell, J Orford, and P.A. King
Subjects: Male, medicine.medical_specialty, medicine.medical_treatment, Bleomycin Injection, Injections, Intralesional, Bleomycin, Skin Discoloration, chemistry.chemical_compound, Sclerotherapy, Lymphangioma, medicine, Humans, Child, Chemotherapy, business.industry, Infant, Cystic hygroma, General Medicine, medicine.disease, Sclerosing Solutions, Surgery, chemistry, Head and Neck Neoplasms, Cellulitis, Pediatrics, Perinatology and Child Health, Vomiting, Female, Lymphangioma, Cystic, medicine.symptom, business
Abstract: Intralesional bleomycin injection was used as sclerosant therapy for sixteen patients with cystic hygroma. An excellent (complete clinical resolution) response was obtained in seven (44%) patients, a good (> 50% response) result in seven (44%), and a poor or no response in two (12%). Minor transient side effects (fever, vomiting, cellulitis, skin discoloration) were seen in six patients, and there were no serious side effects. The results suggest that bleomycin intralesional sclerosant is effective therapy for cystic hygroma, with response rates comparable to those of surgical removal, but with the advantage of avoiding inadvertent nerve damage and scarring.
Published: 1995
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29. Lower threshold energy gamma ray Cerenkov telescopes

Author: K. J. Orford
Subjects: Background noise, Physics, Optics, Lower threshold, Space and Planetary Science, business.industry, Detector, Gamma ray, Astronomy and Astrophysics, Threshold energy, business, Coincidence
Abstract: A method is described for reducing the threshold energy of atmospheric Cerenkov telescopes which comprise two or more light collectors operated in coincidence. The reduction in threshold energy is greater for higher coincidence multiplicity. The method is applicable to any system of two or more detectors which operate with a combination of independent background noise and samples of a common signal.
Published: 1995
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30. Dilated and echogenic fetal bowel and postnatal outcomes: a surgical perspective. Case series and literature review

Author: Jan E. Dickinson, C.R. Jackson, Corrado Minutillo, and J Orford
Subjects: medicine.medical_specialty, Meconium Ileus, Cystic fibrosis, Pregnancy, Echogenic fetal bowel, medicine, Humans, Retrospective Studies, Ultrasonography, business.industry, Obstetrics, Intestinal atresia, Infant, Newborn, Retrospective cohort study, medicine.disease, digestive system diseases, Surgery, Bowel obstruction, Intestines, Fetal Diseases, Intestinal Diseases, medicine.anatomical_structure, Pediatrics, Perinatology and Child Health, Echogenic Bowel, Abdomen, Female, business, Dilatation, Pathologic
Abstract: INTRODUCTION: Foetal dilated or echogenic bowel have been described as markers for a variety of conditions including bowel obstruction, chromosomal and infectious disorders and cystic fibrosis. We aim to describe possible surgical interventions and outcomes. METHODS: A 5-year review was performed of the clinical course of infants with antenatally diagnosed isolated echogenic bowel and/or dilated bowel or intraabdominal echogenic foci presenting at Princess Margaret Hospital for Children, Perth, Western Australia. RESULTS: Abnormal antenatal findings were present in 35 foetuses. Twelve babies underwent surgery for intestinal atresia, meconium ileus and duplication cysts. Postoperative courses and outcomes were good. CONCLUSIONS: Echogenic bowel on antenatal ultrasound is a non-specific marker for a variety of disorders. Although associated with higher rates of foetal loss, the majority of neonates are normal at delivery. Bowel dilatation with or without echogenicity is often predictive of bowel obstruction requiring surgery. Surgical outcomes are, however, very good. Echogenic foci elsewhere in the abdomen have little postnatal significance.
Published: 2010

31. Discovery of VHE γ-rays from the BL Lacertae object PKS 0548-322

Author: Yvonne Becherini, A. Cheesebrough, S. M. Rayner, J. P. Vialle, G. Pedaletti, Joachim Ripken, A. Hoffmann, A. Förster, Martin Raue, J. F. Glicenstein, P.-O. Petrucci, B. Behera, L. Rob, Stefan Wagner, J. L. Skilton, G. Vasileiadis, D. Nekrassov, Michael Punch, J. Ruppel, M. K. Daniel, Christoph Deil, T. Kneiske, M. Kerschhagg, K. Egberts, Anna Szostek, Gilles Henri, L.-M. Chounet, P. M. Chadwick, G. Pelletier, L. Venter, A. C. Clapson, W. Domainko, P. H. Tam, Gerard Fontaine, A. Djannati-Ataï, A. Marcowith, Christo Venter, C. Jahn, Thomas Lohse, Guillaume Dubus, M. de Naurois, J. Brucker, G. Lamanna, F. Volp, M. Panter, U. Katz, E. Moulin, Tomasz Bulik, R. Moderski, M. Füssling, A. Zech, D. Hauser, Frank M. Rieger, T. J. L. McComb, F. Stinzing, A. Shalchi, A. Jacholkowska, B. Giebels, A. R. Bazer-Bachi, S. Schwemmer, S. Rosier-Lees, A. Charbonnier, F. Feinstein, D. Spangler, S. Heinz, Andrea Santangelo, R. C. G. Chaves, O. C. de Jager, J. M. Martin, P. Espigat, D. Khangulyan, W. Kluźniak, B. C. Raubenheimer, U. Barres de Almeida, S. Hoppe, A. Bochow, S. Schwarzburg, S. J. Nolan, D. Keogh, Jacek Niemiec, Jim Hinton, David Maurin, M. Vivier, L. O'c. Drury, C. Boisson, J-F. Olive, Dieter Horns, A. A. Zdziarski, Christian Stegmann, Stefan Ohm, Gavin Rowell, D. Gerbig, J.-P. Tavernet, Gisela Anton, S. Pita, C. B. Rulten, Francois Brun, C. van Eldik, Michal Ostrowski, J. Dyks, J.-P. Lenain, Stefano Gabici, D. Emmanoulopoulos, C. Farnier, Werner Hofmann, D. Nedbal, E. de Oña Wilhelm, G. Heinzelmann, Isak Delberth Davids, Regis Terrier, K. Kosack, Konrad Bernlöhr, A. Fiasson, B. Khélifi, G. Superina, Helene Sol, G. Hermann, G. Pühlhofer, Lukasz Stawarz, Michal Dyrda, K. J. Orford, M. Naumann-Godo, J. Bolmont, Rolf Bühler, Andreas Quirrenbach, B. Nicholas, V. Sahakian, Martin Ward, M. Sikora, Franky Dubois, Felix Aharonian, Reinhard Schlickeiser, F. M. Schöck, Riaan Steenkamp, M. Paz Arribas, Hugh Dickinson, Ullrich Schwanke, M. Dalton, Julien Masbou, M. C. Medina, A. G. Akhperjanian, Eckhard Kendziorra, V. Marandon, M. Hauser, M. Holleran, Heinrich J. Völk, M. Renaud, I. Jung, B. Rudak, Olivier Martineau-Huynh, B. Degrange, I. Büsching, Timothé Boutelier, Nu. Komin, P. Goret, Y. A. Gallant, Sarah Kaufmann, Pascal Vincent, L. Gérard, B. Glück, O. Tibolla, Wystan Benbow, Pierre Brun, D. Göring, V. Borrel, M. Tluczykont, R. Schröder, G. Coignet, Krzysztof Katarzynski, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), HESS, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris
Subjects: BL Lacertae objects: individual: PKS 0548-322, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Swift Gamma-Ray Burst Mission, Photon, Astrophysics::High Energy Astrophysical Phenomena, galaxies: active, Flux, Astrophysics, 7. Clean energy, 01 natural sciences, law.invention, law, 0103 physical sciences, 010303 astronomy & astrophysics, Physics, 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Gamma ray, Astronomy, observations [gamma rays], Astronomy and Astrophysics, Synchrotron, individual: PKS 0548-322 [BL Lacertae objects], Crab Nebula, Space and Planetary Science, active [galaxies], Spectral energy distribution, gamma rays: observations, BL Lac object
Abstract: 6 pages, 3 figures; PKS 0548-322 (z=0.069) is a "high-frequency-peaked'' BL Lac object and a candidate very high energy (VHE, E>100 GeV) gamma-ray emitter, due to its high X-ray and radio flux. Observations at the VHE band provide insights into the origin of very energetic particles present in this source and the radiation processes at work. We report observations made between October 2004 and January 2008 with the H.E.S.S. array, a four imaging atmospheric-Cherenkov telescopes. Contemporaneous UV and X-ray observations with the Swift satellite in November 2006 are also reported. PKS 0548-322 is detected for the first time in the VHE band with H.E.S.S. We measure an excess of 216 gamma-rays corresponding to a significance of 5.6 standard deviations. The photon spectrum of the source is described by a power-law, with a photon index of Gamma=2.86 +/- 0.34 (stat) +/- 0.10 (sys). The integral flux above 200 GeV is 1.3 % of the flux of the Crab Nebula, and is consistent with being constant in time. Contemporaneous Swift/XRT observations reveal an X-ray flux between 2 and 10 keV of F_{2-10 keV}=2.3 +/- 0.2 x 10^{-11} erg.cm^{-2}. s^{-1}, an intermediate intensity state with respect to previous observations. The spectral energy distribution can be reproduced using a simple one-zone synchrotron self Compton model, with parameters similar those observed for other sources of this type.
Published: 2010
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32. Erratum to 'Observations of the Sagittarius dwarf galaxy by the HESS experiment and search for a dark matter signal' [Astropart. Phys. 29(1) (2008) 55--62]

Author: R. Schröder, C. van Eldik, D. Nedbal, Dimitrios Emmanoulopoulos, M. Holleran, S. M. Rayner, J. P. Vialle, G. Coignet, Seb. Funk, S. Schlenker, Conor Masterson, Michael Punch, J. L. Osborne, F. Feinstein, M. Lemoine-Goumard, D. Hauser, M. Beilicke, M. Panter, Luigi Costamante, A. Djannati-Ataï, Reinhard Schlickeiser, Wystan Benbow, A. R. Bazer-Bachi, Heinrich J. Völk, C. Stegmann, A. Shalchi, Rolf Bühler, P. H. Tam, I. Büsching, Kathrin Egberts, S. Schwarzburg, Felix Spanier, B. Degrange, Christian Farnier, Ullrich Schwanke, V. Sahakian, P. Vincent, L. Rolland, T. J. L. McComb, Alexandre Marcowith, O. C. de Jager, P. Espigat, Dieter Horns, Y. A. Gallant, Hugh Dickinson, T. Boutelier, A. Fiasson, C. Boisson, Martin Ward, Eric Nuss, A. G. Akhperjanian, Eckhard Kendziorra, S. Ranchon, M. Vivier, Gilles Henri, D. Spangler, David Berge, Stefan Wagner, Gerd Pühlhofer, C. Hadjichristidis, O. Martineau-Huynh, J.-P. Tavernet, R. Steenkamp, Felix Aharonian, P. M. Chadwick, Ilana M. Braun, Thomas Lohse, A. Lemiere, S. Pita, Guillaume Dubus, M. de Naurois, Helene Sol, M. Tluczykont, Svenja Carrigan, Guillaume Maurin, J. Ripken, B. Khélifi, G. Hermann, Regis Terrier, P.-O. Petrucci, L. Saugé, Werner Hofmann, Karl Kosack, I. J. Latham, G. Pelletier, J.-P. Olive, L.-M. Chounet, Stefan Funk, B. Giebels, S. Schwemmer, V. Borrel, Andrea Santangelo, Christo Venter, P. Goret, Luke O'c. Drury, B. C. Raubenheimer, E. Ferrero, Martin Raue, M. Füßling, Gavin Rowell, A. Hoffmann, G. Lamanna, B. Glück, A. Jacholkowska, A. M. Brown, E. Brion, J. F. Glicenstein, G. Fontaine, L. Rob, S. Hoppe, R. Le Gallou, M. Kerschhaggl, G. Vasileiadis, G. Heinzelmann, S. J. Nolan, J. M. Martin, M. Hauser, Nu. Komin, O. Bolz, Konrad Bernlöhr, G. Superina, Jim Hinton, K. J. Orford, R. Cornils, S. Rosier-Lees, E. Moulin, A. Noutsos, Faure, Alexandre, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Kernphysik (MPIK), Yerevan Physics Institute, Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Heinrich Heine Universität Düsseldorf = Heinrich Heine University [Düsseldorf], CERN [Genève], Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Department of Physics, University of Durham, South Road, Unit for Space Physics, North-West University, Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Dublin Institute for Advanced Studies (DIAS), Landessternwarte Königstuhl (LSW), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Humboldt University Of Berlin, Dr. Karl Remeis-Sternwarte, Astronomisches Institut, Universität Erlangen-Nuremberg, Eberhard Karls Universität Tübingen = Eberhard Karls University of Tuebingen, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institute of Particle and Nuclear Physics, Charles University (IPNP), University of Adelaide, Institut für Theoretische Physik, Ruhr-Universität Bochum, and University of Namibia
Subjects: Physics, 010308 nuclear & particles physics, Milky Way, Dark matter, Astronomy, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, Signal, Dwarf spheroidal galaxy, Dark matter halo, 0103 physical sciences, 010306 general physics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Sagittarius, Galaxy rotation curve, ComputingMilieux_MISCELLANEOUS, Dwarf galaxy
Abstract: International audience
Published: 2010
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33. 350 GeV gamma rays from AE Aqr

Author: S. M. Rayner, J. E. Dickinson, P. M. Chadwick, S.M. Bradbury, E. W. Lincoln, T. J. L. McComb, K. J. Orford, K. E. Turver, P. J. Edwards, C. C. G. Bowden, and Nigel Dipper
Subjects: Physics, Wavelength, Gamma ray, Astronomy, Astronomy and Astrophysics, Astrophysics, Dark period
Abstract: We report here the results of VHE γ-ray observations made during 1990 and 1991 using the Durham University Mark III and IV VHE γ-ray telescopes at Narrabri, N.S.W., Australia. There are 4 separate datasets, each obtained from observations over typically 10 days during a lunar dark period. The dataset from October 1990 exhibits periodicity at a chance probability of 1 × 10 -4 , and a similar effect is noted in the dataset from August 1991 at 1.6 × 10 −2 . In both cases, most of the power is in the second harmonic; the period is constant over at least 10 days and similar to that seen at optical wavelengths. No significant signal was detected in the September 1991 and October 1991 datasets. In addition, a strong and highly significant outburst lasting about 1 minute on 13 October 1990 and detected by two independent telescopes is reported. This outburst shows the 33 s periodic pulse structure and the pulses are in phase with those observed during the strongest sustained periodic signal in our data, from an observation lasting 3 h and taken 48 h previously. A second, weaker burst was also observed during August 1991.
Published: 1992
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34. Further observations of VHE gamma rays from Vela X-1

Author: E. W. Lincoln, T. J. L. McComb, S. M. Bradbury, C. C. G. Bowden, Nigel Dipper, K. E. Turver, P. J. Edwards, K. J. Orford, S. M. Rayner, J. E. Dickinson, and P. M. Chadwick
Subjects: Physics, Nuclear and High Energy Physics, Pulsar, Signal strength, Gamma ray, Astronomy, Astrophysics, Vela
Abstract: Observations of Vel X-1 were made in February 1991 using the University of Durham Mark III and IV VHE gamma-ray telescopes at Narrabri, New South Wales, Australia. The complete data-set shows evidence for weak but apparently constant periodicity at the X-ray pulsar period with a signal strength compatible with the authors' earlier measurements. In addition, on two occasions (February 13 and February 22 1991) they have evidence for short (1800 s) outbursts of emission of gamma rays modulated with the pulsar period. These outbursts occur at the same orbital phase (0.68), and the periodic effects noted during the outbursts have probabilities of change occurrence of 5.9*10-4 and 4.4*10-7.
Published: 1992
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35. The effect of the geomagnetic field on TeV gamma -ray detection

Author: Nigel Dipper, K. E. Turver, K. J. Orford, P. J. Edwards, S. M. Rayner, C. C. G. Bowden, S. M. Bradbury, P. M. Chadwick, E. W. Lincoln, T. J. L. McComb, and J. E. Dickinson
Subjects: Physics, Nuclear and High Energy Physics, Range (particle radiation), Proton, Field (physics), High-energy astronomy, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics, law.invention, Atmosphere, Telescope, Crab Nebula, Earth's magnetic field, law
Abstract: Very high energy (VHE) gamma -ray astronomy using the ground based atmospheric Cerenkov technique is an important new field of high energy astrophysics and a range of VHE gamma -ray sources has been detected at various levels of significance by a number of experimental groups. Outstanding evidence for gamma -rays from the Crab Nebula was obtained by the Whipple collaboration. This involved the use of a sophisticated technique based on computer simulations to select gamma -ray-like events from the proton induced background When this same technique was applied to data from other sources detected using an earlier version of the Whipple telescope, the evidence for a gamma -ray signal disappeared. The inability to reconcile the Whipple result from the Crab Nebula with both the failure of the Whipple camera to detect other objects and the detections made with other non-imaging telescopes has caused some concern at a critical time in the evolution of this branch of high energy astrophysics. In an attempt to reconcile these results, the authors have made a detailed study of the effects of the geomagnetic field on the electron-photon cascades. They have simulated the Cerenkov light produced by individual protons and gamma -rays at different orientations in the atmosphere, and made measurements of the sensitivity of the observations to the geomagnetic field. Indications are that these geomagnetic effects may be a cause of the differing results.
Published: 1992
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36. Detection of Gamma Rays From a Starburst Galaxy

Author: S. Schwarzburg, J. Dyks, O. C. de Jager, Jim Hinton, U. Schwanke, Dmitry Khangulyan, Frank M. Rieger, M. K. Daniel, W. Kluźniak, M. Kerschhaggl, R. C. G. Chaves, J-F. Olive, K. J. Orford, S. Hoppe, M. Vivier, B. Behera, Stefan Ohm, Anna Szostek, F. Dubois, Petter Hofverberg, Dimitrios Emmanoulopoulos, L. Rob, Nu. Komin, Stefan Wagner, M. de Naurois, Gisela Anton, S. Schwemmer, P. Espigat, Alexandre Marcowith, Y. A. Gallant, P. Goret, J. Mehault, Andrea Santangelo, A. A. Zdziarski, M. Naumann-Godo, S. Rosier-Lees, Emmanuel Moulin, A. Charbonnier, F. Stinzing, G. Pedaletti, J.-P. Lenain, S. Heinz, J. Ripken, Francesca Volpe, M. Panter, B. Nicholas, Jacek Niemiec, M. Füßling, E. de Oña Wilhelmi, G. Fontaine, Olaf Reimer, J.F. Glicenstein, Sarah Kaufmann, U. Barres de Almeida, A. C. Clapson, F. Brun, L. Gérard, B. Glück, A. Djannati-Ataï, Tomasz Bulik, J. Ruppel, L.-M. Chounet, D. Klochkov, G. Vasileiadis, Guillaume Dubus, A. Jacholkowska, Michael Punch, J. Brucker, F. Feinstein, D. Göring, Olivier Martineau-Huynh, D. Keogh, A. Bochow, W. Domainko, P. H. Tam, Gavin Rowell, David Maurin, A. Fiasson, Julien Masbou, Thomas Lohse, V. Borrel, V. Sahakian, Michal Dyrda, Timothé Boutelier, Stefano Gabici, P.-O. Petrucci, Yvonne Becherini, S. J. Nolan, Rolf Bühler, Andreas Quirrenbach, G. Lamanna, Christian Farnier, B. C. Raubenheimer, M. Renaud, J. P. Tavernet, M. C. Medina, Dieter Horns, Konrad Bernlöhr, G. Superina, G. Pühlhofer, D. Nekrassov, Werner Hofmann, Michał Ostrowski, Fabio Acero, K. Katarzyński, A. R. Bazer-Bachi, B. Khélifi, German Hermann, Regis Terrier, Catherine Boisson, Christoph Deil, T. Kneiske, D. Gerbig, Gilles Henri, Pierre Brun, D. Nedbal, S. Pita, M. Tluczykont, P. Vincent, Martin Ward, Cameron B Rulten, M. Sikora, Felix Aharonian, Stephen Fegan, T. J. L. McComb, A. Hoffmann, K. Kosack, J. L. Skilton, Łukasz Stawarz, Heinrich J. Völk, C. van Eldik, L. Venter, G. Coignet, M. Hauser, D. Hauser, I. Büsching, A. Cheesebrough, R. Kossakowski, O. Tibolla, L. O'c. Drury, C. Stegmann, I. Jung, R. Steenkamp, B. Rudak, Kathrin Egberts, B. Degrange, G. Heinzelmann, J. Bolmont, Christo Venter, C. Jahn, U. F. Katz, R. Moderski, A. Zech, Reinhard Schlickeiser, Hugh Dickinson, V. Marandon, I. D. Davids, P. M. Chadwick, M. Raue, S. M. Rayner, J. P. Vialle, Guy Pelletier, B. Giebels, A. Förster, Helene Sol, F. M. Schöck, M. Paz Arribas, M. Dalton, A. G. Akhperjanian, A. Shalchi, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), HESS, Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), Astroparticle physics, Physics, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Multidisciplinary, 010308 nuclear & particles physics, Milky Way, Astrophysics::High Energy Astrophysical Phenomena, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Gamma ray, FOS: Physical sciences, Astronomy, Cosmic ray, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Electromagnetic radiation, Galaxy, 3. Good health, Supernova, 0103 physical sciences, Astrophysics - High Energy Astrophysical Phenomena, 010303 astronomy & astrophysics, Cherenkov radiation, Astrophysics::Galaxy Astrophysics
Abstract: Starburst galaxies exhibit in their central regions a highly increased rate of supernovae, the remnants of which are thought to accelerate energetic cosmic rays up to energies of ~ 10^15 eV. We report the detection of gamma rays -- tracers of such cosmic rays -- from the starburst galaxy NGC 253 using the H.E.S.S. array of imaging atmospheric Cherenkov telescopes. The gamma-ray flux above 220 GeV is F = (5.5 +/- 1.0stat +/- 2.8sys) x 10^-13 ph. s-1 cm-2, implying a cosmic-ray density about three orders of magnitude larger than that in the center of the Milky Way. The fraction of cosmic-ray energy channeled into gamma rays in this starburst environment is 5 times larger than that in our Galaxy., 24 pages, 8 figures, published in Science Express, see: http://www.sciencemag.org/cgi/content/abstract/1178826
Published: 2009
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37. Very high energy gamma-ray observations of the galaxy clusters Abell 496 and Abell 85 with H.E.S.S

Author: F. Aharonian, A. G. Akhperjanian, G. Anton, U. Barres de Almeida, A. R. Bazer-Bachi, Y. Becherini, B. Behera, K. Bernlöhr, C. Boisson, A. Bochow, V. Borrel, I. Braun, E. Brion, J. Brucker, P. Brun, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L.-M. Chounet, A. C. Clapson, G. Coignet, M. Dalton, M. K. Daniel, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, M. Füßling, S. Gabici, Y. A. Gallant, L. Gérard, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, I. Jung, K. Katarzyński, U. Katz, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khélifi, D. Keogh, Nu. Komin, K. Kosack, G. Lamanna, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, M. C. Medina, R. Moderski, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Oña Wilhelmi, K. J. Orford, M. Ostrowski, M. Panter, M. Paz Arribas, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. Rudak, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, J. L. Skilton, H. Sol, D. Spangler, Ł. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, A. Szostek, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, C. van Eldik, G. Vasileiadis, C. Venter, L. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), HESS, Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)
Subjects: [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::High Energy Astrophysical Phenomena, Flux, FOS: Physical sciences, Cosmic ray, IACT, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Gamma rays: observations, 01 natural sciences, 7. Clean energy, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], 0103 physical sciences, Cluster (physics), 010303 astronomy & astrophysics, Galaxy cluster, Abell 85, Physics, Accretion (meteorology), 010308 nuclear & particles physics, Astrophysics (astro-ph), Gamma ray, observations [gamma rays], Astronomy and Astrophysics, Galaxy, Space and Planetary Science, clusters: individual: Abell 496 [galaxies], Galaxies: clusters: individual: Abell 496, clusters: individual: Abell 85 [galaxies]
Abstract: Aims: The nearby galaxy clusters Abell 496 and Abell 85 are studied in the very high energy (VHE, E > 100 GeV) band to investigate VHE cosmic rays (CRs) in this class of objects which are the largest gravitationally bound systems in the Universe. Methods: H.E.S.S., an array of four Imaging Atmospheric Cherenkov Telescopes (IACT), is used to observe the targets in the range of VHE gamma rays. Results: No significant gamma-ray signal is found at the respective position of the two clusters with several different source size assumptions for each target. In particular, emission regions corresponding to the high density core, to the extension of the entire X-ray emission in these clusters, and to the very extended region where the accretion shock is expected, are investigated. Upper limits are derived for the gamma-ray flux at energies E>570 GeV for Abell 496 and E>460 GeV for Abell 85. Conclusions: From the non-detection in VHE gamma rays, upper limits on the total energy of hadronic CRs in the clusters are calculated. If the cosmic-ray energy density follows the large scale gas density profile, the limit on the fraction of energy in these non-thermal particles with respect to the total thermal energy of the intra-cluster medium (ICM) is 51% for Abell 496 and only 8% for Abell 85 due to its larger mass and higher gas density. These upper limits are compared with theoretical estimates. They predict about ~10% of the thermal energy of the ICM in non-thermal particles. The observations presented here can constrain these predictions especially for the case of the Abell 85 cluster., 11 pages, 4 figures, accepted for publication in A&A
Published: 2009
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38. HESS upper limits on very high energy gamma-ray emission from the microquasar GRS 1915+105

Author: O. C. de Jager, S. Vorobiov, M. Vivier, Jim Hinton, G. Fontaine, Michael Punch, Joachim Ripken, Dmitry Khangulyan, M. Kerschhaggl, V. Sahakian, D. Keogh, Michał Ostrowski, Werner Hofmann, Stefan Wagner, Gisela Anton, M. Hauser, G. Pedaletti, J.-P. Lenain, M. K. Daniel, K. J. Orford, Francesca Volpe, A. Hoffmann, B. Nicholas, C. van Eldik, R. C. G. Chaves, Pierre Brun, M. Holleran, S. Hoppe, A. Shalchi, J. F. Glicenstein, A. C. Clapson, Guillaume Dubus, S. J. Nolan, Christian Farnier, D. Göring, Dieter Horns, P. M. Chadwick, Andreas Quirrenbach, S. Schwemmer, Gilles Henri, Frank M. Rieger, I. Büsching, S. Pita, S. Schwarzburg, Andrea Santangelo, A. A. Zdziarski, A. Djannati-Ataï, M. Tluczykont, L.-M. Chounet, M. Panter, D. Klochkov, Reinhard Schlickeiser, Rafal Moderski, Christoph Deil, Y. A. Gallant, T. Kneiske, Nu. Komin, B. Giebels, J. Dyks, A. Cheesebrough, Hugh Dickinson, W. Kluźniak, B. Behera, P. Goret, Jan Conrad, V. Marandon, L. Rob, P.-O. Petrucci, I. D. Davids, B. Khélifi, D. Nekrassov, Yvonne Becherini, G. Hermann, J. L. Skilton, Regis Terrier, W. Domainko, P. H. Tam, L. Fallon, A. Jacholkowska, Anna Szostek, F. Dubois, Christo Venter, D. Nedbal, Marek Sikora, M. Füßling, Petter Hofverberg, E. de Oña Wilhelmi, F. M. Schöck, G. Lamanna, C. Jahn, M. Paz Arribas, Sarah Kaufmann, U. F. Katz, G. Vasileiadis, V. Borrel, A. Zech, Ullrich Schwanke, S. M. Rayner, M. Dalton, L. Gérard, A. Charbonnier, Michal Dyrda, B. Glück, J. P. Vialle, Łukasz Stawarz, H. Sol, Cameron B Rulten, S. Heinz, P. Espigat, Tomasz Bulik, A. G. Akhperjanian, B. C. Raubenheimer, Guy Pelletier, R. Steenkamp, A. Förster, Martin Raue, O. Tibolla, M. Renaud, A. Fiasson, Thomas Lohse, Timothé Boutelier, A. R. Bazer-Bachi, Jacek Niemiec, Heinrich J. Völk, L. O'c. Drury, Olaf Reimer, G. Heinzelmann, Gavin Rowell, J. Bolmont, D. Gerbig, Felix Aharonian, J. Ruppel, Catherine Boisson, Peter Eger, Stephen Fegan, R. de los Reyes, J. Brucker, Emmanuel Moulin, M. Naumann-Godo, F. Stinzing, P. Vincent, C. Stegmann, Martin Ward, Felix Ryde, Iurii Sushch, R. Kossakowski, I. Jung, B. Rudak, Kathrin Egberts, B. Degrange, A. Bochow, S. Rosier-Lees, K. Kosack, Konrad Bernlöhr, G. Superina, G. Pühlhofer, Fabio Acero, Stefan Ohm, J-F. Olive, G. Coignet, K. Katarzyński, M. de Naurois, Alexandre Marcowith, J. Mehault, David Maurin, L. Venter, J.-P. Tavernet, T. J. L. McComb, F. Feinstein, F. Brun, Julien Masbou, Stefano Gabici, U. Barres de Almeida, A. Schönwald, M. C. Medina, Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), HESS, Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)
Subjects: [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::High Energy Astrophysical Phenomena, Context (language use), Astrophysics, 01 natural sciences, Luminosity, law.invention, Telescope, X-rays: binaries, Astrophysical jet, law, individuals: GRS 1915+105 [X-rays], 0103 physical sciences, 010303 astronomy & astrophysics, Cherenkov radiation, Astrophysics::Galaxy Astrophysics, X-rays: individuals: GRS 1915+105, Astroparticle physics, Physics, 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Gamma ray, Astronomy, observations [gamma rays], Astronomy and Astrophysics, Particle acceleration, Space and Planetary Science, binaries [X-rays], gamma rays: observations
Abstract: Context. High energy particles reside in the relativistic jets of microquasars, making them possible sources of very high energy radiation (VHE, >100 GeV). Detecting this emission would provide a new handle on jet physics. Aims. Observations of the microquasar GRS 1915+105 with the HESS telescope array were undertaken in 2004-2008 to search for VHE emission. Methods. Stereoscopic imaging of Cherenkov radiation from extensive air showers is used to reconstruct the energy and direction of the incident gamma rays. Results. There is no evidence for a VHE gamma-ray signal either from the direction of the microquasar or its vicinity. An upper limit of $6.1\times 10^$ ph cm-2 s-1 (99.9% confidence level) is set on the photon flux above 410 GeV, equivalent to a VHE luminosity of ${\sim} 10^$ erg s-1 at 11 kpc. Conclusions. The VHE to X-ray luminosity ratio in GRS 1915+105 is at least four orders of magnitude lower than the ratio observed in gamma-ray binaries. The VHE radiative efficiency of the compact jet is less than 0.01% based on its estimated total power of 1038 erg s-1. Particle acceleration in GRS 1915+105 is not efficient at high energies and/or the magnetic field is too strong. It is also possible that VHE gamma-rays are produced by GRS 1915+105, but the emission is highly time-dependent.
Published: 2009
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39. HESS observations of $\gamma$-ray bursts in 2003-2007

Author: F. Aharonian, A. G. Akhperjanian, U. Barres de Almeida, A. R. Bazer-Bachi, B. Behera, W. Benbow, K. Bernlöhr, C. Boisson, A. Bochow, V. Borrel, I. Braun, E. Brion, J. Brucker, P. Brun, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, S. Carrigan, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L.-M. Chounet, A. C. Clapson, G. Coignet, M. Dalton, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, M. Füßling, S. Gabici, Y. A. Gallant, L. Gérard, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, C. Hadjichristidis, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, I. Jung, K. Katarzyński, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khélifi, D. Keogh, Nu. Komin, K. Kosack, G. Lamanna, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, M. C. Medina, R. Moderski, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Oña Wilhelmi, K. J. Orford, J. L. Osborne, M. Ostrowski, M. Panter, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. Rudak, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, J. L. Skilton, H. Sol, D. Spangler, Ł. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, C. van Eldik, G. Vasileiadis, C. Venter, L. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, and A. Zech
Subjects: Physics, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Instrumentation and Methods for Astrophysics, Flux, bursts [gamma rays], observations [gamma rays], Astronomy and Astrophysics, Astrophysics, Photon energy, 01 natural sciences, Redshift, Space and Planetary Science, 0103 physical sciences, Background light, Gamma-ray burst, 010303 astronomy & astrophysics, Cherenkov radiation
Abstract: Very-high-energy (VHE; >~100 GeV) gamma-rays are expected from gamma-ray bursts (GRBs) in some scenarios. Exploring this photon energy regime is necessary for understanding the energetics and properties of GRBs. GRBs have been one of the prime targets for the H.E.S.S. experiment, which makes use of four Imaging Atmospheric Cherenkov Telescopes (IACTs) to detect VHE gamma-rays. Dedicated observations of 32 GRB positions were made in the years 2003-2007 and a search for VHE gamma-ray counterparts of these GRBs was made. Depending on the visibility and observing conditions, the observations mostly start minutes to hours after the burst and typically last two hours. Results from observations of 22 GRB positions are presented and evidence of a VHE signal was found neither in observations of any individual GRBs, nor from stacking data from subsets of GRBs with higher expected VHE flux according to a model-independent ranking scheme. Upper limits for the VHE gamma-ray flux from the GRB positions were derived. For those GRBs with measured redshifts, differential upper limits at the energy threshold after correcting for absorption due to extra-galactic background light are also presented.
Published: 2009

40. Simultaneous multiwavelength observations of the second exceptional $\gamma$-ray flare of PKS 2155–304 in July 2006

Author: F. Aharonian, A. G. Akhperjanian, G. Anton, U. Barres de Almeida, A. R. Bazer-Bachi, Y. Becherini, B. Behera, W. Benbow, K. Bernlöhr, C. Boisson, A. Bochow, V. Borrel, E. Brion, J. Brucker, P. Brun, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L.-M. Chounet, A. C. Clapson, G. Coignet, L. Costamante, M. Dalton, M. K. Daniel, I. D. Davids, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, M. Füßling, S. Gabici, Y. A. Gallant, L. Gérard, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, D. Göhring, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, C. Jahn, I. Jung, K. Katarzyński, U. Katz, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khélifi, D. Keogh, W. Kluźniak, T. Kneiske, Nu. Komin, K. Kosack, G. Lamanna, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, M. C. Medina, R. Moderski, L. A. G. Monard, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Oña Wilhelmi, K. J. Orford, M. Ostrowski, M. Panter, M. Paz Arribas, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. Rudak, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, M. Sikora, J. L. Skilton, H. Sol, D. Spangler, Ł. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, A. Szostek, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, M. Tluczykont, C. van Eldik, G. Vasileiadis, C. Venter, L. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), HESS, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO), [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::High Energy Astrophysical Phenomena, Phase (waves), FOS: Physical sciences, Astrophysics, 01 natural sciences, Spectral line, law.invention, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Flux (metallurgy), law, 0103 physical sciences, 010303 astronomy & astrophysics, PKS 2155-304, Physics, 010308 nuclear & particles physics, Gamma ray, observations [gamma rays], Astronomy and Astrophysics, Light curve, galaxies [X-rays], Space and Planetary Science, active [galaxies], BL Lacertae objects: individual: PKS 2155–304 [galaxies], Astrophysics - Cosmology and Nongalactic Astrophysics, Flare, BL Lac object
Abstract: Simultaneous HESS/CHANDRA/optical observations were performed on the BL Lac object PKS 2155-304 in the night of July 29-30 2006, when the source underwent its second major gamma-ray outburst in Summer 2006. This event took place about 44 hours after the July 28 outburst, known for its ultrafast variability. An unprecedented 6 to 8 hours of uninterrupted coverage was achieved, with spectra and light curves measured down to 7 and 2-minute timescales, respectively. The gamma-ray flux reached a maximum of 11x the Crab flux (>400 GeV), with rise/decay timescales of ~1 hour, plus a few smaller-amplitude flares superimposed on the decaying phase. The emission in the X-ray and VHE bands is strongly correlated, both in flux and spectrum, with no evidence of lags. The VHE spectrum shows a curvature that is variable with time and stronger at higher fluxes. The huge VHE variations (22x) are only accompanied by small-amplitude X-ray and optical variations (factor 2 and 15% respectively). The source has shown for the first time in an HBL a large Compton dominance (L_C/L_S ~10) -- rapidly evolving -- and a cubic relation between VHE and X-ray flux variations, during a decaying phase. These results challenge the common scenarios for the TeV-blazar emission., 22 pages, 16 figures, accepted for publication in A&A
Published: 2009
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41. Discovery of very high energy $\gamma$-ray emission from Centaurus A with H.E.S.S

Author: F. Aharonian, A. G. Akhperjanian, G. Anton, U. Barres de Almeida, A. R. Bazer-Bachi, Y. Becherini, B. Behera, W. Benbow, K. Bernlöhr, C. Boisson, A. Bochow, V. Borrel, E. Brion, J. Brucker, P. Brun, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L.-M. Chounet, A. C. Clapson, G. Coignet, M. Dalton, M. K. Daniel, I. D. Davids, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, M. Füßling, S. Gabici, Y. A. Gallant, L. Gérard, B. Giebels, J.-F. Glicenstein, B. Glück, P. Goret, D. Göhring, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, C. Jahn, I. Jung, K. Katarzyński, U. Katz, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khélifi, D. Keogh, W. Kluźniak, T. Kneiske, Nu. Komin, K. Kosack, G. Lamanna, I. J. Latham, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, M. C. Medina, R. Moderski, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Oña Wilhelmi, K. J. Orford, M. Ostrowski, M. Panter, M. Paz Arribas, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. Rudak, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, M. Sikora, J. L. Skilton, H. Sol, D. Spangler, Ł. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, A. Szostek, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, M. Tluczykont, C. van Eldik, G. Vasileiadis, C. Venter, L. Venter, J. P. Vialle, P. Vincent, J. Vink, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), HESS, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO), Radio galaxy, [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::High Energy Astrophysical Phenomena, Centaurus A, FOS: Physical sciences, Flux, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Luminosity, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], individual (Cen A) [galaxies], 0103 physical sciences, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, 010308 nuclear & particles physics, Gamma ray, observations [gamma rays], Astronomy and Astrophysics, Cherenkov Telescope Array, Particle acceleration, Crab Nebula, Space and Planetary Science, active [galaxies], Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We report the discovery of faint very high energy (VHE, E>100 GeV) gamma-ray emission from the radio galaxy Centaurus A in observations performed with the H.E.S.S. experiment, an imaging atmospheric Cherenkov telescope array consisting of four telescopes located in Namibia. Centaurus A has been observed for more than 120 h. A signal with a statistical significance of 5.0 sigma is detected from the region including the radio core and the inner kpc jets. The integral flux above an energy threshold of ~250 GeV is measured to be ~0.8 % of the flux of the Crab Nebula (apparent luminosity: L(>250 GeV)~2.6x10^39 erg s^-1, adopting a distance of 3.8 Mpc. The spectrum can be described by a power law with a photon index of 2.7 +/- 0.5_stat +/- 0.2_sys. No significant flux variability is detected in the data set. However, the low flux only allows detection of variability on the timescale of days to flux increments above a factor of ~15-20 (3 sigma and 4 sigma, respectively). The discovery of VHE gamma-ray emission from Centaurus A reveals particle acceleration in the source to >TeV energies and, together with M 87, establishes radio galaxies as a class of VHE emitters., 5 pages, 4 figures, accepted for publication in ApJ Letters
Published: 2009
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42. A search for a dark matter annihilation signal towards the Canis Major overdensity with H.E.S.S

Author: F. Aharonian, A. G. Akhperjanian, U. Barres de Almeida, A. R. Bazer-Bachi, B. Behera, W. Benbow, K. Bernlöhr, C. Boisson, V. Bochow, V. Borrel, I. Braun, E. Brion, J. Brucker, P. Brun, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, S. Carrigan, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L.-M. Chounet, A. C. Clapson, G. Coignet, L. Costamante, M. Dalton, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, M. Füssling, S. Gabici, Y. A. Gallant, L. Gérard, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, C. Hadjichristidis, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, I. Jung, K. Katarzyński, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khélifi, D. Keogh, Nu. Komin, K. Kosack, G. Lamanna, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, C. Medina, R. Moderski, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Oña Wilhelmi, K. J. Orford, J. L. Osborne, M. Ostrowski, M. Panter, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. Rudak, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, J. L. Skilton, H. Sol, D. Spangler, L. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, C. van Eldik, G. Vasileiadis, C. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), APC - Astrophysique des Hautes Energies (APC - AHE), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), AstroParticule et Cosmologie (APC (UMR_7164)), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), HESS, Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)
Subjects: Structure formation, dwarf [galaxies], [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::High Energy Astrophysical Phenomena, Dark matter, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, dark matter, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], WIMP, 0103 physical sciences, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Dwarf galaxy, Physics, Annihilation, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astrophysics (astro-ph), Order (ring theory), observations [gamma rays], Astronomy and Astrophysics, Space and Planetary Science, Neutralino, Halo
Abstract: A search for a dark matter (DM) annihilation signal into $\gamma$-rays toward the direction of the Canis Major (CMa) overdensity is presented. The nature of CMa is still controversial and one scenario represents it as a dwarf galaxy, making it an interesting candidate for DM annihilation searches. A total of 9.6 hours of high quality data were collected with the H.E.S.S. array of Imaging Atmospheric Cherenkov Telescopes (IACTs) and no evidence for a very high energy $\gamma$-ray signal is found. Upper limits on the CMa dwarf galaxy mass of the order of 10$^{9}$ M$_{\odot}$ are derived at the 95% C.L. assuming neutralino masses in the range 500 GeV - 10 TeV and relatively large annihilation cross-sections. Constraints on the velocity-weighted annihilation cross section $$, are calculated for specific WIMP scenarios, using a NFW model for the DM halo profile and taking advantage of numerical simulations of hierarchical structure formation. 95% C.L. exclusion limits of the order of 5 $\times$ 10$^{-24}$ cm$^{3}$ s$^{-1}$ are reached in the 500 GeV - 10 TeV DM particle mass interval, assuming a total halo mass of 3 $\times$ 10$^{8}$ M$_{\odot}$., Comment: Accepted for publication in ApJ
Published: 2009
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43. HESS Observations and VLT Spectroscopy of PG 1553+113

Author: G. Heinzelmann, K. J. Orford, David Maurin, J.-P. Tavernet, J.-P. Lenain, W. Domainko, F. Schock, A. A. Zdziarski, P. H. Tam, Gerard Fontaine, J. Ripken, Michał Ostrowski, J. Ruppel, Gerd Pühlhofer, Gavin Rowell, A. Djannati-Ataï, Seb. Funk, R. Schröder, F. Dubois, Dimitrios Emmanoulopoulos, A. R. Bazer-Bachi, F. Feinstein, L. O'c. Drury, Felix Aharonian, V. Sahakian, B. Behera, Helene Sol, D. Spangler, Jean Michel Martin, Anne Lemiere, E. de Oña Wilhelmi, O. C. de Jager, Conor Masterson, L. Rob, P. Espigat, Nu. Komin, D. Nedbal, Luigi Costamante, Michael Punch, Christo Venter, C. Farnier, A. Fiasson, A. Shalchi, D. Keogh, P. Goret, Reinhard Schlickeiser, Karl Kosack, M. Vivier, A. Zech, G. Coignet, B. Khélifi, Hugh Dickinson, G. Hermann, Rolf Bühler, D. Hauser, Stefan Wagner, S. Schwarzburg, M. Füßling, M. Beilicke, G. Vasileiadis, Thomas Lohse, B. C. Raubenheimer, U. Barres de Almeida, Werner Hofmann, Martin Ward, B. Glück, Stefan Ohm, Wystan Benbow, S. M. Rayner, J. P. Vialle, Olivier Martineau-Huynh, S. Pita, A. C. Clapson, C. Hadjichristidis, J.-P. Olive, Dieter Horns, Timothé Boutelier, Ullrich Schwanke, M. Dalton, V. Borrel, A. Förster, Martin Raue, J. Dyks, J. L. Osborne, Regis Terrier, Guillaume Dubus, C. Boisson, Y. A. Gallant, A. G. Akhperjanian, Eckhard Kendziorra, P. M. Chadwick, M. Kerschhaggl, R. Steenkamp, Pascal Vincent, M. de Naurois, Heinrich J. Völk, K. Katarzynski, Gilles Henri, Rafal Moderski, Konrad Bernlöhr, Jim Hinton, B. Giebels, G. Superina, A. Hoffmann, E. Brion, J. F. Glicenstein, Matthieu Renaud, R. Cornils, S. Rosier-Lees, A. M. Brown, T. J. L. McComb, Svenja Carrigan, G. Pelletier, I. J. Latham, L. Stawarz, Emmanuel Moulin, C. Stegmann, I. Jung, B. Rudak, Kathrin Egberts, B. Degrange, S. Schwemmer, Andrea Santangelo, S. Ranchon, M. Panter, Ilana M. Braun, P.-O. Petrucci, Gilles Maurin, Tomasz Bulik, A. Jacholkowska, L. Rolland, M. Hauser, S. J. Nolan, C. van Eldik, M. Holleran, G. Lamanna, S. Hoppe, I. Büsching, O. Bolz, L.-M. Chounet, A. Marcowith, M. Lemoine-Goumard, G. Pedaletti, Francesca Volpe, Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), APC - Astrophysique des Hautes Energies (APC - AHE), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), AstroParticule et Cosmologie (APC (UMR_7164)), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), HESS, Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), 10859748 - Holleran, Mathew, 12006653 - Venter, Christo, 10065857 - De Jager, Ocker Cornelis, 13235176 - Büsching, Ingo, and 10179240 - Raubenheimer, Barend Christoffel
Subjects: [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], FOS: Physical sciences, Flux, Astrophysics, 01 natural sciences, Spectral line, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], BL Lacertae objects: individual: PG1553+113 [galaxies], 0103 physical sciences, Emission spectrum, High Energy Stereoscopic System, Spectroscopy, 010303 astronomy & astrophysics, BL Lacertae objects: individual: PG 1553+113 [galaxies], Physics, Very Large Telescope, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astrophysics (astro-ph), observations [gamma rays], Astronomy, Astronomy and Astrophysics, Redshift, Crab Nebula, Space and Planetary Science, active [galaxies]
Abstract: AIMS: The properties of the very high energy (VHE; E>100 GeV) gamma-ray emission from the high-frequency peaked BL Lac PG 1553+113 are investigated. An attempt is made to measure the currently unknown redshift of this object. METHODS: VHE Observations of PG 1553+113 were made with the High Energy Stereoscopic System (HESS) in 2005 and 2006. H+K (1.45-2.45 micron) spectroscopy of PG 1553+113 was performed in March 2006 with SINFONI, an integral field spectrometer of the ESO Very Large Telescope (VLT) in Chile. RESULTS: A VHE signal, ~10 standard deviations, is detected by HESS during the 2 years of observations (24.8 hours live time). The integral flux above 300 GeV is (4.6 +- 0.6{stat} +- 0.9{syst}) x 10^{-12} cm^{-2} s^{-1}, corresponding to ~3.4% of the flux from the Crab Nebula above the same threshold. The time-averaged energy spectrum is measured from 225 GeV to ~1.3 TeV, and is characterized by a very soft power law (photon index of Gamma = 4.5 +- 0.3{stat} +- 0.1{syst}). No evidence for any flux or spectral variations is found on any sampled time scale within the VHE data. The redshift of PG 1553+113 could not be determined. Indeed, even though the measured SINFONI spectrum is the most sensitive ever reported for this object at near infrared wavelengths, and the sensitivity is comparable to the best spectroscopy at other wavelengths, no absorption or emission lines were found in the H+K spectrum presented here., 9 pages, 12 Figures; Accepted for publication in Astronomy & Astrophysics; (Revision has simple typo in table 1 MJD column corrected.)
Published: 2008
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44. H.E.S.S. Observations of the Prompt and Afterglow Phases of GRB 060602B

Author: F. Aharonian, A. G. Akhperjanian, U. Barres De Almeida, A. R. Bazer-Bachi, B. Behera, M. Beilicke, W. Benbow, K. Bernlöhr, C. Boisson, V. Borrel, I. Braun, E. Brion, J. Brucker, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, S. Carrigan, P. M. Chadwick, R. Chaves, L.-M. Chounet, A. C. Clapson, G. Coignet, R. Cornils, L. Costamante, M. Dalton, B. Degrange, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, M. Füßling, S. Gabici, Y. A. Gallant, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, C. Hadjichristidis, D. Hauser, M. Hauser, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, I. Jung, K. Katarzyński, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khélifi, D. Keogh, Nu. Komin, K. Kosack, G. Lamanna, I. J. Latham, J.-P. Lenain, T. Lohse, J. M. Martin, O. Martineau-Huynh, A. Marcowith, C. Masterson, D. Maurin, T. J. L. McComb, R. Moderski, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, S. J. Nolan, S. Ohm, J.-P. Olive, E. de Oña Wilhelmi, K. J. Orford, J. L. Osborne, M. Ostrowski, M. Panter, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. Rudak, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, H. Sol, D. Spangler, Ł. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, P. H. Tam, J.-P. Tavernet, R. Terrier, C. van Eldik, G. Vasileiadis, C. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), APC - Astrophysique des Hautes Energies (APC - AHE), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), AstroParticule et Cosmologie (APC (UMR_7164)), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), HESS, Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)
Subjects: [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::High Energy Astrophysical Phenomena, Flux, FOS: Physical sciences, Context (language use), Astrophysics, 01 natural sciences, law.invention, Telescope, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], law, 0103 physical sciences, High Energy Stereoscopic System, 010303 astronomy & astrophysics, Cherenkov radiation, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Galactic Center, Astrophysics (astro-ph), bursts [gamma rays], observations [gamma rays], Astronomy and Astrophysics, 3. Good health, Afterglow, 13. Climate action, Space and Planetary Science, Gamma-ray burst
Abstract: We report on the first completely simultaneous observation of a gamma-ray burst (GRB) using an array of Imaging Atmospheric Cherenkov Telescopes which is sensitive to photons in the very-high-energy (VHE) gamma-ray range (>~100 GeV). On 2006 June 2, the Swift Burst Alert Telescope (BAT) registered an unusually soft gamma-ray burst (GRB 060602B). The burst position was under observation using the High Energy Stereoscopic System (H.E.S.S.) at the time the burst occurred. Data were taken before, during, and after the burst. A total of 5 hours of observations were obtained during the night of 2006 June 2-3, and 5 additional hours were obtained over the next 3 nights. No VHE gamma-ray signal was found during the period covered by the H.E.S.S. observations. The 99% confidence level flux upper limit (>1 TeV) for the prompt phase (9s) of GRB 060602B is 2.9x10^-9 erg cm^-2 s^-1. Due to the very soft BAT spectrum of the burst compared to other Swift GRBs and its proximity to the Galactic center, the burst is likely associated with a Galactic X-ray burster, although the possibility of it being a cosmological GRB cannot be ruled out. We discuss the implications of our flux limits in the context of these two bursting scenarios., 8 pages, 4 figures, 1 table; ApJ in press
Published: 2008
Full Text: View/download PDF

45. HESS very-high-energy gamma-ray sources without identified counterparts

Author: F. Aharonian, A. G. Akhperjanian, U. Barres de Almeida, A. R. Bazer-Bachi, B. Behera, M. Beilicke, W. Benbow, K. Bernlöhr, C. Boisson, O. Bolz, V. Borrel, I. Braun, E. Brion, A. M. Brown, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, S. Carrigan, P. M. Chadwick, L.-M. Chounet, A. C. Clapson, G. Coignet, R. Cornils, L. Costamante, M. Dalton, B. Degrange, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, S. Funk, M. Füßling, Y. A. Gallant, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, C. Hadjichristidis, D. Hauser, M. Hauser, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, I. Jung, K. Katarzyński, E. Kendziorra, M. Kerschhaggl, B. Khélifi, D. Keogh, Nu. Komin, K. Kosack, G. Lamanna, I. J. Latham, A. Lemière, M. Lemoine-Goumard, J.-P. Lenain, T. Lohse, J. M. Martin, O. Martineau-Huynh, A. Marcowith, C. Masterson, D. Maurin, G. Maurin, T. J. L. McComb, R. Moderski, E. Moulin, M. de Naurois, D. Nedbal, S. J. Nolan, S. Ohm, J.-P. Olive, E. de Oña Wilhelmi, K. J. Orford, J. L. Osborne, M. Ostrowski, M. Panter, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, S. Ranchon, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, J. Ripken, L. Rob, L. Rolland, S. Rosier-Lees, G. Rowell, B. Rudak, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, H. Sol, D. Spangler, Ł. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, P. H. Tam, J.-P. Tavernet, R. Terrier, C. van Eldik, G. Vasileiadis, C. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), APC - Astrophysique des Hautes Energies (APC - AHE), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), AstroParticule et Cosmologie (APC (UMR_7164)), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), HESS, Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC)
Subjects: [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], media_common.quotation_subject, Astrophysics::High Energy Astrophysical Phenomena, Population, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Spectral line, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], cosmic rays, surveys, 0103 physical sciences, education, 010303 astronomy & astrophysics, Galaxy: general, Cherenkov radiation, general [Galaxy], media_common, Physics, Astrophysical Processes, education.field_of_study, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Gamma ray, observations [gamma rays], Astronomy and Astrophysics, Galactic plane, Galaxy, Space and Planetary Science, Sky, gamma rays: observations
Abstract: Context.The detection of gamma rays in the very-high-energy (VHE) energy range (100 GeV-100 TeV) provides a direct view of the parent population of ultra-relativistic particles found in astrophysical sources. For this reason, VHE gamma rays are useful for understanding the underlying astrophysical processes in non-thermal sources. Aims.We investigate unidentified VHE gamma-ray sources that have been discovered with HESS in the most sensitive blind survey of the Galactic plane at VHE energies conducted so far. Methods.The HESS array of imaging atmospheric Cherenkov telescopes (IACTs) has a high sensitivity compared with previous instruments (~ in 25 h observation time for a point-source detection), and with its large field of view, is well suited for scan-based observations. The on-going HESS survey of the inner Galaxy has revealed a large number of new VHE sources, and for each we attempt to associate the VHE emission with multi-wavelength data in the radio through X-ray wavebands. Results. For each of the eight unidentified VHE sources considered here, we present the energy spectra and sky maps of the sources and their environment. The VHE morphology is compared with available multi-wavelength data (mainly radio and X-rays). No plausible counterparts are found.
Published: 2008
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46. Enhancement of the gamma ray signal in atmospheric Cerenkov light measurements using the University of Durham VHE gamma ray telescopes

Author: Nigel Dipper, E. W. Lincoln, T. J. L. McComb, K. E. Turver, K. T. S. Brazier, P. M. Chadwick, A. Carraminana, K. J. Orford, S. M. Rayner, and V. G. Mannings
Subjects: Physics, Nuclear and High Energy Physics, business.industry, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Instrumentation and Methods for Astrophysics, Gamma ray, Astronomy, Cosmic ray, Field of view, Atomic and Molecular Physics, and Optics, law.invention, Telescope, Optics, Crab Nebula, Pulsar, law, business, Cherenkov radiation, Fermi Gamma-ray Space Telescope
Abstract: The design of two types of very high energy (VHE) gamma ray telescope which have the capability to enhance the gamma ray signal is discussed. The performance of the array of Cerenkov light telescopes operated at Dugway from 1981 – 1984 to provide within field of view arrival direction measurements from inter telescope fast timing is assessed, and is compared with that of a large telescope now operating at Narrabri which has focal plane detectors incorporating a coincidence “guard ring” system. We conclude that the coincidence guard ring technique applied to a large collecting area telescope offers the greater sensitivity.
Published: 1990
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47. 400 Gev gamma rays from the X-ray pulsar 1E2259+586

Author: E. W. Lincoln, T. J. L. McComb, K. T. S. Brazier, Nigel Dipper, S. M. Rayner, K. E. Turver, A. Carraminana, V. G. Mannings, K. J. Orford, and P. M. Chadwick
Subjects: Physics, Nuclear and High Energy Physics, Radiation flux, Pulsar, Gamma ray, Astronomy, Cosmic ray, Astrophysics, Electromagnetic radiation, Atomic and Molecular Physics, and Optics, Luminosity, X-ray pulsar, Fermi Gamma-ray Space Telescope
Abstract: We report observations of the X-ray pulsar 1E2259+586 made in 1988 October using the very high energy gamma ray telescope operating in La Palma. We find evidence significant at the 5.3 × 10 −5 level for the emission of 400 GeV gamma rays pulsating at 6.9790s. The flux of gamma rays is (2.0 ± 0.8) × 10 −10 cm −2 s −1 corresponding to VHE gamma ray luminosity of (5.3 ± 2.1) × 10 35 erg s −1 .
Published: 1990
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48. Analytical treatment of oversampling

Author: K. J. Orford
Subjects: Physics, Monte Carlo method, Analytical technique, Astronomy and Astrophysics, Data set, symbols.namesake, Fourier transform, Space and Planetary Science, symbols, Oversampling, Rayleigh scattering, Algorithm, Statistic, Statistical hypothesis testing
Abstract: During searches for periodicity in very high energy (VHE) gamma ray data, the freedom usually exists to place a trial period anywhere within the spacing between independent periods normally associated with a Fourier transform of data of finite duration. The problem has been previously addressed by Monte Carlo techniques, which are limited by the demands of computing time to small data sets and signal strengths. This letter provides an analytical technique for calculating the oversampling factor for any data set size and any statistical test. The method is illustrated using the Rayleigh statistic, which is widely used in testing for periodicity
Published: 1990
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49. The fiber specificity of the cotton FSltp4 gene promoter is regulated by an AT-rich promoter region and the AT-hook transcription factor GhAT1

Author: Sharon J. Orford, Jeremy N. Timmis, Sven K Delaney, and Michael Martin-Harris
Subjects: Physiology, Transgene, Response element, Molecular Sequence Data, Plant Science, AT-hook, Biology, Transcription (biology), Gene Expression Regulation, Plant, Tobacco, Amino Acid Sequence, Cotton Fiber, Promoter Regions, Genetic, Gene, Transcription factor, Plant Proteins, Gossypium, Base Sequence, Promoter, Cell Biology, General Medicine, Plants, Genetically Modified, Molecular biology, Plant Leaves, Fiber cell, Transcription Factors
Abstract: Fiber-specific genes are expressed preferentially or exclusively in cotton (Gossypium spp.) fiber and are thought to have important functions in fiber development. The promoters of these genes are of interest because they control transcription in the fiber cell and may be used in the genetic manipulation of fiber quality. The promoter of a cotton lipid transfer protein gene, FSltp4, was isolated and shown to direct fiber-specific transcription of an abundant mRNA in cotton. In transgenic tobacco, this promoter was strongly active in leaf trichomes. Deletion analysis of the promoter identified an AT-rich 84 bp fiber specificity region (FSR) necessary for activity exclusively in the fiber cells. Cotton fiber proteins that bind the FSR were isolated using a yeast one-hybrid assay. One of these was a putative AT-hook transcription factor (GhAT1) containing two AT-hook motifs. GhAT1 was shown to be nuclear localized, and GhAT1 transcripts were found to be preferentially expressed in ovules and non-fiber tissues. Overexpression of GhAT1 strongly repressed the activity of the FSltp4 promoter in the trichomes of transgenic tobacco. These results suggest that GhAT1 assists in the specification of fiber cells by repressing FSltp4 in the non-fiber tissues of the cotton plant.
Published: 2007

50. Detection of extended very-high-energy gamma-ray emission towards the young stellar cluster Westerlund 2

Author: F. Aharonian, A. G. Akhperjanian, A. R. Bazer-Bachi, M. Beilicke, W. Benbow, D. Berge, K. Bernlöhr, C. Boisson, O. Bolz, V. Borrel, I. Braun, E. Brion, A. M. Brown, R. Bühler, I. Büsching, T. Boutelier, S. Carrigan, P. M. Chadwick, L.-M. Chounet, G. Coignet, R. Cornils, L. Costamante, B. Degrange, H. J. Dickinson, A. Djannati-Ataï, L. O'C. Drury, G. Dubus, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, E. Ferrero, A. Fiasson, G. Fontaine, Seb. Funk, S. Funk, M. Füßling, Y. A. Gallant, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, C. Hadjichristidis, D. Hauser, M. Hauser, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, E. Kendziorra, M. Kerschhaggl, B. Khélifi, Nu. Komin, K. Kosack, G. Lamanna, I. J. Latham, R. Le Gallou, A. Lemière, M. Lemoine-Goumard, T. Lohse, J. M. Martin, O. Martineau-Huynh, A. Marcowith, C. Masterson, G. Maurin, T. J. L. McComb, E. Moulin, M. de Naurois, D. Nedbal, S. J. Nolan, A. Noutsos, J-P. Olive, K. J. Orford, J. L. Osborne, M. Panter, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, S. Ranchon, B. C. Raubenheimer, M. Raue, S. M. Rayner, A. Reimer, O. Reimer, J. Ripken, L. Rob, L. Rolland, S. Rosier-Lees, G. Rowell, V. Sahakian, A. Santangelo, L. Saugé, S. Schlenker, R. Schlickeiser, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, H. Sol, D. Spangler, F. Spanier, R. Steenkamp, C. Stegmann, G. Superina, P. H. Tam, J.-P. Tavernet, R. Terrier, M. Tluczykont, C. van Eldik, G. Vasileiadis, C. Venter, J. P. Vialle, P. Vincent, H. J. Völk, S. J. Wagner, M. Ward, Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), APC - Astrophysique des Hautes Energies (APC - AHE), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), HESS, Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)
Subjects: [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::High Energy Astrophysical Phenomena, ISM: star forming regions, FOS: Physical sciences, RCW 49 (NGC 3247, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, law.invention, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Telescope, law, 0103 physical sciences, Cluster (physics), Astrophysics::Solar and Stellar Astrophysics, ISM: individual objects: HESS J1023-575, 010303 astronomy & astrophysics, Cherenkov radiation, Astrophysics::Galaxy Astrophysics, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astrophysics (astro-ph), Gamma ray, Astronomy and Astrophysics, G284.3-0.3), Interstellar medium, Stars, 13. Climate action, Space and Planetary Science, WR 20a, Light emission, gamma rays: observations, Open cluster
Abstract: Results from gamma-ray observations by the H.E.S.S. telescope array in the direction of the young stellar cluster Westerlund 2 are presented. Stereoscopic imaging of Cherenkov light emission of gamma-ray induced showers in the atmosphere is used to study the celestial region around the massive Wolf-Rayet (WR) binary WR 20a. Spectral and positional analysis is performed using standard event reconstruction techniques and parameter cuts. The detection of a new gamma-ray source is reported from H.E.S.S. observations in 2006. HESS J1023-575 is found to be coincident with the young stellar cluster Westerlund 2 in the well-known HII complex RCW 49. The source is detected with a statistical significance of more than 9 sigma, and shows extension beyond a point-like object within the H.E.S.S. point-spread function. The differential gamma-ray spectrum of the emission region is measured over approximately two orders of magnitude in flux. The spatial coincidence between HESS J1023-575 and the young open cluster Westerlund 2, hosting e.g. the massive WR binary WR 20a, requires a look into a variety of potential models to account for the observed very-high-energy (VHE) gamma-ray emission. Considered emission scenarios include emission from the colliding wind zone of WR 20a, collective stellar winds from the extraordinary ensemble of hot and massive stars in the stellar cluster Westerlund 2, diffusive shock acceleration in the wind-blown bubble itself, and supersonic winds breaking out into the interstellar medium (ISM). The observed source extension argues against a single star origin of the observed VHE emission., 7 pages, 5 figures, accepted for publication in A&A
Published: 2007
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