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201. 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

202. Reconfigurable Multifunctional Operation Using Optical Injection-Locked Vertical-Cavity Surface-Emitting Lasers

Author

Constance J. Chang-Hasnain, Devang Parekh, Werner Hofmann, Alan E. Willner, Bo Zhang, Xiaoxue Zhao, M.-C. Amann, and Yang Yue

Subjects
Injection locking, Engineering, Interferometry, Optics, Multi-mode optical fiber, business.industry, Single-mode optical fiber, Delay line interferometer, business, Optical filter, Atomic and Molecular Physics, and Optics, Clock recovery, Vertical-cavity surface-emitting laser
Abstract

In this paper, we extend the system application of optical injection-locked (OIL) vertical-cavity surface-emitting lasers (VCSELs) to future optical networks by realizing multifunctional operation using a filter-assisted OIL-VCSEL scheme that can be reconfigured. By using a single chirp-adjustable injection-locked VCSEL (either single mode or multimode) followed by a tunable delay line interferometer, we experimentally demonstrate three functions, showing ultra-wide band (UWB) monocycle generation, nonreturn-to-zero (NRZ) to pseudoreturn-to-zero (PRZ) data format conversion, and NRZ-data clock recovery at 10 Gb/s.

Published
2009

203. Size-distribution dependent lung deposition of diesel exhaust particles

Author

Barouch Giechaskiel, B. Alföldy, Werner Hofmann, and Yannis Drossinos

Subjects
Fluid Flow and Transfer Processes, Atmospheric Science, Environmental Engineering, Diesel exhaust, Particle number, Chemistry, Mechanical Engineering, Analytical chemistry, Nucleation, Mineralogy, Fraction (chemistry), Pollution, Deposition (aerosol physics), Ultrafine particle, Mass concentration (chemistry), Mass fraction
Abstract

Lung deposition fractions of nine experimental particle number distributions emitted by various light duty diesel vehicles with different after-treatment devices and fuels were calculated with a stochastic lung deposition model. The emitted volatile and non-volatile mass fractions were treated separately as the corresponding biological response in the human respiratory tract differs. The health related effects of the volatile mass fraction, referred to as the chemical effect, were associated with the deposited volatile mass. The deposited volatile mass depends on the total emitted volatile mass concentration, on its distribution (mass median diameter of nucleation mode and surface area median of the accumulation mode), and on the ratio of the volatile mass in the nucleation and accumulation modes. The effect of the non-volatile mass fraction, referred to as the physical effect, was associated with the surface area distribution of the accumulation mode. The deposited surface area of the non-volatile fraction depends on its emitted concentration and on the surface area median diameter of the size distribution. The calculations suggest the importance of selecting the appropriate distribution (surface, volatile or non-volatile mass) for an assessment of the health effects of diesel exhaust particles, and the importance of combined particulate mass and number distribution measurements.

Published
2009

204. V0 production in p+A collisions at $\sqrt{s}=41.6$ GeV

Author

A. Michetti, Y. Guilitsky, S. Kupper, T. Hott, B. Lewendel, P. Conde, S. Xella-Hansen, Igor Golutvin, K. Ehret, J. Kessler, Antonio Sbrizzi, Yu. Zaitsev, Peter Buchholz, Y. Bagaturia, T. Jagla, X. Dong, Ll. Garrido, T. Kvaratskheliia, H. Deppe, E. B. Klinkby, Laura Silva, P. Kreuzer, F. Sanchez, S. Solunin, Wouter Hulsbergen, C. Bauer, I. Gorbounov, Andrej Gorišek, A. H. Walenta, D. Reßing, C. Cruse, A. J. Schwartz, Jose M Hernandez, M. A. Pleier, I. Massa, M. Danilov, Helmut Wolters, Farid Ould-Saada, Maurizio Piccinini, A. Belkov, U. Schwanke, B. Giacobbe, R. Spighi, J. Bastos, R. Pernack, D. Krücker, S. Prystupa, Yu. A. Golubkov, O. Igonkina, M. Funcke, M. Poli, R. Pestotnik, I. Abt, H. Rick, O. Barsukova, A. Bertin, T. Živko, Mikhail Zavertyaev, Valery Pugatch, A. Zhelezov, Laura Fabbri, Alexander Spiridonov, S. Essenov, M. Adams, S. De Castro, J. Groth-Jensen, M. zur Nedden, I. Rostovtseva, M. T. Nunez Pardo de Vera, M. Agari, A. Stanovnik, N.N. Karpenko, S. Keller, C. Padilla, Kwong Lau, Antonio Zoccoli, H. Schröder, Ulrich Werthenbach, A. S. Schwarz, Y. Vassiliev, H. B. Dreis, T. Zeuner, Vladimir Popov, U. Uwer, S. Masciocchi, F. Eisele, João Carvalho, H. Albrecht, K. M. Danielsen, J. Gläß, B. Lomonosov, M. Medinnis, M. Negodaev, A. Wurz, S. Karabekyan, J. Spengler, Y. Pylypchenko, Nicola Semprini-Cesari, Dmitry Emeliyanov, R. Mankel, Mauro Villa, Vasco Amaral, Reinhard Männer, R. Wurth, D. Pose, M. Nörenberg, M. Feuerstack-Raible, Mogens Dam, A. Bogatyrev, R. Mizuk, B. Schmidt, Imma Riu, Samo Korpar, C. Stegmann, Marcus Hohlmann, P. Križan, A. Golutvin, B. Bobchenko, Z. Zheng, Th. S. Bauer, A. Vitale, C. B. Krauss, C. van Eldik, U. Husemann, L. Sozuer, S. J. Aplin, B. Schwingenheuer, I. Kisel, A. Lanyov, I. Matchikhilian, R. Zimmermann, T. Buran, M. Böcker, B. A. Petersen, J. Pyrlik, Pietro Faccioli, V. Aushev, M. Ispiryan, F. Sciacca, S. Gradl, I. Belotelov, H. Kapitza, V. Rybnikov, I. Tsakov, M. Bruinsma, Kendall Reeves, Marco Bruschi, Maksym Titov, F. Grimaldi, M. Symalla, Vladislav Balagura, J. J. Wang, A. Schreiner, H. S. Subramania, J.D. Hansen, M. Bräuer, M. Walter, F. Khasanov, M. Starič, J. Batista, António Amorim, A. Somov, D. Peralta, I. Vukotic, Peter Robmann, K. T. Knöpfle, G. Medin, S. Somov, Aleksandar Aleksandrov, M. Ouchrif, R. Muresan, C. Jiang, I. Tikhomirov, B. Schwenninger, Yu.T. Kiryushin, M. Bargiotti, Sebastian Nowak, D. Wegener, S. Shuvalov, H. Wahlberg, W. Gradl, M. Schmelling, J. Flammer, B. Fominykh, Yu.V. Mikhailov, D. C. Goulart, Werner Hofmann, A. Gellrich, O. Gouchtchine, G. Bohm, Hermann Kolanoski, Thomas Lohse, D. Goloubkov, V. Egorytchev, and M. Mevius

Subjects
Astrofísica, Teoria quàntica de camps, Physics and Astronomy (miscellaneous), Astronomy, Nuclear physics, Astrophysics, 01 natural sciences, Partícules (Física nuclear), High Energy Physics - Experiment, symbols.namesake, Cross section (physics), String models, 0103 physical sciences, Feynman diagram, ddc:530, Nuclear Experiment, 010306 general physics, Engineering (miscellaneous), Particles (Nuclear physics), Physics, Models de corda, 010308 nuclear & particles physics, Hyperon, Function (mathematics), Quantum field theory, Transverse plane, Astronomia, symbols, High Energy Physics::Experiment, Física nuclear, Production (computer science), Atomic number, Atomic physics, Bar (unit)
Abstract

Inclusive doubly differential cross sections d^2\sigma_{pA}/dx_Fdp_T^2 as a function of Feynman-x (x_F) and transverse momentum (p_T) for the production of K^0_s, Lambda^0 and anti-Lambda^0 in proton-nucleus interactions at 920 GeV are presented. The measurements were performed by HERA-B in the negative x_F range (-0.12, Comment: 17 pages, 9 figures, 8 tables; minor revisions based on comments from the journal referee

Published
2009

205. Stochastic Aspects of Primary Cellular Consequences of Radon Inhalation

Author

István Szőke, Árpád Farkas, Werner Hofmann, and Imre Balásházy

Subjects
Models, Anatomic, New Mexico, Respiratory System, Biophysics, chemistry.chemical_element, Radon, Inhaled air, Radiation Dosage, Models, Biological, Mining, Particle dynamics, Humans, Dosimetry, Radiology, Nuclear Medicine and imaging, Radiometry, Cell Nucleus, Inhalation Exposure, Stochastic Processes, Radiation, Cell Death, Inhalation, Epithelial Cells, Alpha Particles, respiratory tract diseases, Radiation exposure, chemistry, Cellular distribution, Uranium, Biological system, Bronchial epithelium
Abstract

In this study, a composite, biophysical mechanism-based microdosimetric model was developed for the assessment of the primary cellular consequences of radon inhalation. Based on the concentration of radio-aerosols in the inhaled air and the duration of exposure, this mathematical approach allows the computation of the distribution of cellular burdens and the resulting distribution of cellular inactivation and oncogenic transformation probabilities within the epithelium of the human central airways. The composite model is composed of three major parts. The first part is a lung-particle interaction model applying computational fluid and particle dynamics (CFPD) methods. The second part is a lung dosimetry model that quantifies the cellular distribution of radiation exposure within the bronchial epithelium. The third part of the composite model is the unit-track-length model, which allows the prediction of the biological outcome of the exposure at the cellular level. Computations were made for different exposure durations for a miner working in a New Mexico uranium mine. The spatial pattern of the exposed cell nuclei along the epithelium, the distributions of single and multiple alpha-particle hits, the distributions of cell nucleus doses, and cell inactivation and cell transformation probabilities as a function of the number of inhalations (length of exposure) were investigated and compared for up to 500 inhalations.

Published
2009

206. InP-Based Long-Wavelength VCSELs and VCSEL Arrays

Author

Werner Hofmann and Markus-Christian Amann

Subjects
Materials science, business.industry, Laser, Multiplexing, Atomic and Molecular Physics, and Optics, Vertical-cavity surface-emitting laser, Semiconductor laser theory, law.invention, Optics, Tunnel junction, law, Wavelength-division multiplexing, Optoelectronics, Equivalent circuit, Laser power scaling, Electrical and Electronic Engineering, business
Abstract

Long-wavelength, InP-based, vertical-cavity surface-emitting lasers with buried tunnel junction (LW-BTJ-VCSELs) and VCSEL arrays are presented. Emitting at the telecommunications wavelengths around 1.3 and 1.55 mum, these devices show high modulation bandwidth in excess of 10 GHz over a wide temperature range. Small-signal equivalent circuits for the parasitic and intrinsic response are given. Various data-transmission experiments are performed with data rates up to 12.5 Gb/s over different fiber channels. 1-D LW-BTJ-VCSEL arrays can be used in wavelength-division multiplexing systems for high bandwidth per fiber channel. 2-D high-speed arrays with 64 individually addressable channels are presented that are particularly suited for optical ultrabroadband interconnects. Furthermore, large-scale arrays are investigated for high-power applications. In a detailed investigation, we derive scaling rules considering the influence of aperture, array size, and pitch on laser power. At room temperature, optical output powers in the watt regime have been realized at 1.55 mum. Divergence angles are as low as 13deg-17deg full-width at half-maximum. Wall plug efficiencies in excess of 20% over a wide current range and high-temperature operation up to 80degC are obtained.

Published
2009

207. Modellrechnungen zur Deposition nicht-sphärischer Teilchen in den oberen Luftwegen der menschlichen Lunge

Author

Robert Sturm and Werner Hofmann

Subjects
Gynecology, Physics, medicine.medical_specialty, Radiological and Ultrasound Technology, Biophysics, medicine, Radiology, Nuclear Medicine and imaging
Abstract

Zusammenfassung Im vorliegenden Beitrag soll ein Computermodell zur Beschreibung der Deposition nicht-spharischer Teilchen im oberen respiratorischen Trakt des Menschen zur Vorstellung gelangen. Als Grundlage fur die theoretische Approximation dient das Konzept des aerodynamischen Durchmessers, dessen Berechnung auf neuesten Erkenntnissen erfolgte und auf dessen Basis Depositionsmuster fur verschiedene Teilchenarten (Fasern und Plattchen) und Atmungsbedingungen (Atmung im Sitzen, bei leichter sowie bei schwerer Tatigkeit) simuliert wurden. Bei zylindrischen Fasern mit einem Durchmesser ⩾1 μ m bewirkt eine Steigerung der aspect ratio β (=Teilchenlange/Teilchendurchmesser) eine signifikante Verschiebung der Deposition in die obersten Bereiche des Respirationstraktes (Oropharynx, Larynx, Trachea), wobei entsprechender Effekt durch die Erhohung des inhalativen Flusses noch eine zusatzliche Verstarkung erfahrt. Bei oblaten Partikeln mit einem Durchmesser ⩾1 μ m wird durch die Verringerung der aspect ratio eine Verlagerung der Deposition in tiefere Lungenregionen, also der umgekehrte Effekt wie bei den Fasern bewirkt. Die Erhohung des Inhalationsflusses fuhrt hier nur bedingt zu einer Effektumkehrung.

Published
2009

208. Modelling of cell deaths and cell transformations of inhaled radon in homes and mines based on a biophysical and microdosimetric model

Author

Imre Balásházy, Werner Hofmann, Árpád Farkas, and István Szőke

Subjects
Cell Death, Radiological and Ultrasound Technology, New Mexico, chemistry.chemical_element, Soil science, Radon, Models, Biological, Mining, respiratory tract diseases, Toxicology, Uranium mine, Cell Transformation, Neoplastic, Inhalation, chemistry, Air Pollutants, Radioactive, Particle dynamics, Air Pollution, Indoor, Body Burden, Humans, Environmental science, Dosimetry, Radiology, Nuclear Medicine and imaging, Radiometry, Lung
Abstract

In this study a biophysical mechanism-based microdosimetric model was applied to predict the biological effects of inhaled radon progenies in homes and in uranium mines.The radon daughter concentrations of more than 2000 homes were averaged in case of home exposure and the New Mexico uranium mine data were used in case of exposure in mines. The complex microdosimetric model applied in this work was developed by combining a computational fluid and particle dynamics (CFPD) lung model with a lung dosimetry model that quantify the local distribution of radiation burden and the Unit-Track-Length Model, which characterizes the biological outcome of the exposure.Our results show that the inhomogeneity of radon daughter deposition is stronger in the case of mines. Consequently, the numbers of cells which receive multiple hits and the maxima of radiation burdens are significantly higher in mines. In contrast to this, the distributions and maximum values of cell transformation probabilities are very similar in the two cases.If the same amounts of inhaled progenies are considered then primary cellular consequences are very similar in case of homes and mines, however, the local maxima of radiation burden are higher in mines.

Published
2008

209. Semi-Empirical Stochastic Model of Aerosol Bolus Dispersion in the Human Lung

Author

Ełzbieta Pawłak, Werner Hofmann, and Robert Sturm

Subjects
Aerosols, Models, Anatomic, Stochastic Processes, Chemistry, Stochastic modelling, Quantitative Biology::Tissues and Organs, Health, Toxicology and Mutagenesis, Physics::Medical Physics, Monte Carlo method, Exhalation, Mechanics, respiratory system, Toxicology, Standard deviation, respiratory tract diseases, Aerosol, Bolus (medicine), Anesthesia, Administration, Inhalation, Convective mixing, Humans, Computer Simulation, Lung, Bifurcation
Abstract

Aerosol bolus dispersion, that is, the broadening of an inhaled narrow aerosol bolus upon exhalation, was simulated by Monte Carlo methods using a stochastic, asymmetric morphometric model of the human lung. Physical mechanisms considered to contribute to bolus dispersion were (1) axial diffusion in conductive airways, approximated by effective diffusivities, (2) convective mixing at airway bifurcation sites, (3) differences in inspiratory and expiratory velocity profiles, (4) mixing with residual air in alveoli, and (5) inhomogeneous ventilation of the lung lobes due to asymmetric flow spitting at bifurcations and asymmetric and asynchronous filling of the five lung lobes. Theoretical predictions of the bolus dispersion model were compared to experimental data for 79 healthy volunteers, which provide detailed information on statistical bolus parameters (half-width, standard deviation, skewness, and mode shift) and total bolus deposition as a function of the depth of bolus penetration into the airway system. Predicted bolus dispersion and deposition data show excellent agreement with the published experimental data, suggesting that axial diffusion in conductive airways and convective mixing in alveoli, resulting in irreversible particle transport, are the major determinants of bolus dispersion. The variability and asymmetry of the branching airway network, leading to asymmetric flow splitting at airway bifurcations, greatly enhances the effect of irreversibility and the resulting dispersion of the inhaled bolus.

Published
2008

210. Single-mode and tunable VCSELs in the near- to mid-infrared

Author

Markus-Christian Amann and Werner Hofmann

Subjects
Tunable diode laser absorption spectroscopy, Materials science, business.industry, Single-mode optical fiber, Laser, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, law.invention, Vertical-cavity surface-emitting laser, Wavelength, Optics, law, Wavelength-division multiplexing, Optoelectronics, Electrical and Electronic Engineering, business, Tunable laser, Spectral purity
Abstract

Single-mode, long-wavelength vertical-cavity surface-emitting lasers (VCSELs) in the near- to mid-infrared covering the wavelength range from 1.3 to 2.3 are presented. This wide spectral emission range opens applications in gas sensing and optical interconnects. All these lasers are monolithically grown in the InGaAlAs-InP material system utilizing a buried tunnel junction (BTJ) as current aperture. Fabricated with a novel high-speed design with reduced parasitics, bandwidths in excess of 10 GHz at 1.3 and 1.55 µm have been achieved. Therefore, the coarse wavelength division multiplexing (CWDM) wavelength range of 1.3 to 1.6 µm at 10 Gb/s can be accomplished with one technology. Error-free data-transmission at 10 Gb/s over a fiber link of 20 km is demonstrated. One-dimensional arrays have been fabricated with emission wavelengths addressable by current tuning. Micro-electro-mechanical system (MEMS) tunable devices provide an extended tuning range in excess of 50 nm with high spectral purity. All these devices feature continuous-wave (CW) operation with typical single-mode output powers exceeding 1 mW. The operation voltage is around 1-1.5 V and power consumption is as low as 10-20 mW. Furthermore, we have also developed VCSELs based on GaSb, targeting at the wavelength range from 2.3 to 3.0 µm. The functionality of tunable diode laser spectroscopy (TDLS) systems is shown by presenting a laser hygrometer applying a 1.84-µm VCSEL.

Published
2008

211. Detrimental and Protective Bystander Effects: A Model Approach

Author

J. L. Redpath, Douglas Crawford-Brown, Werner Hofmann, R. E. J. Mitchel, and Helmut Schöllnberger

Subjects
Radiation, Cell Survival, Low dose, Biophysics, Dose-Response Relationship, Radiation, Bystander Effect, Biology, Radiation Dosage, Models, Biological, Article, Cell Transformation, Neoplastic, Cytoprotection, Apoptosis, Immunology, Bystander effect, Computer Simulation, Radiology, Nuclear Medicine and imaging, Neoplastic transformation, Cell survival
Abstract

This work integrates two important cellular responses to low doses, detrimental bystander effects and apoptosis-mediated protective bystander effects, into a multistage model for chromosome aberrations and in vitro neoplastic transformation: the State-Vector Model. The new models were tested on representative data sets that show supralinear or U-shaped dose responses. The original model without the new low-dose features was also tested for consistency with LNT-shaped dose responses. Reductions of in vitro neoplastic transformation frequencies below the spontaneous level have been reported after exposure of cells to low doses of low-LET radiation. In the current study, this protective effect is explained with by-stander-induced apoptosis. An important data set that shows a low-dose detrimental bystander effect for chromosome aberrations was successfully fitted by additional terms within the cell initiation stage. It was found that this approach is equivalent to bystander-induced clonal expansion of initiated cells. This study is an important step toward a comprehensive model that contains all essential biological mechanisms that can influence dose–response curves at low doses.

Published
2007

212. Measurement of D0, D+, Ds + and D*+ production in fixed target 920 GeV proton–nucleus collisions

Author

Laura Silva, D. Goloubkov, I. Matchikhilian, Maurizio Piccinini, V. Egorytchev, S. Solunin, I. Abt, R. Pernack, M. Mevius, F. Sanchez, Peter Robmann, P. Kreuzer, B. Schwenninger, H. B. Dreis, Vladimir Popov, C. B. Krauss, I. Belotelov, H. S. Subramania, D. Skrk, M. Schmelling, U. Schwanke, B. Lomonosov, Dmitry Emeliyanov, Marcus Hohlmann, S. De Castro, K. M. Danielsen, Reinhard Männer, Yu.T. Kiryushin, U. Husemann, M. Medinnis, Y. Pylypchenko, Mikhail Zavertyaev, R. Zimmermann, J. Flammer, I. Rostovtseva, Y. Vassiliev, O. Barsukova, A. H. Walenta, H. Schröder, M. Adams, J. J. Wang, S. Shuvalov, Z. Zheng, M. Ispiryan, T. Živko, S. Gradl, Thomas Lohse, Mauro Villa, S. Essenov, E. B. Klinkby, S. Keller, S. Somov, S. Karabekyan, M. Bräuer, M. Walter, Aleksandar Aleksandrov, A. Gellrich, F. Eisele, M. Ouchrif, O. Gouchtchine, R. Muresan, M. Nörenberg, N.N. Karpenko, Vladislav Balagura, G. Bohm, J.D. Hansen, Laura Fabbri, J. Groth-Jensen, Hermann Kolanoski, J. Bastos, Imma Riu, António Amorim, C. Padilla, H. Deppe, P. Križan, V. Rybnikov, S. Kupper, I. Tikhomirov, A. Golutvin, B. Bobchenko, K. T. Knöpfle, C. van Eldik, Andrej Gorišek, Nicola Semprini-Cesari, A. Belkov, L. Garrido, M. Negodaev, C. Stegmann, A. Bogatyrev, M. Feuerstack-Raible, Mogens Dam, A. Schreiner, A. Vitale, T. Buran, J. Gläß, D. Krücker, I. Kisel, J. Spengler, S. Xella-Hansen, B. A. Petersen, Pietro Faccioli, Yu. A. Golubkov, V. Aushev, B. Fominykh, I. Tsakov, Yu.V. Mikhailov, A. Lanyov, R. Spighi, F. Sciacca, F. Grimaldi, S. Korpar, C. Bauer, D. C. Goulart, D. Reßing, M. Symalla, A. J. Schwartz, Jose M Hernandez, R. Pestotnik, Werner Hofmann, A. Michetti, H. Albrecht, M. Böcker, Marco Bruschi, I. Gorbounov, A. Bertin, B. Lewendel, Peter Buchholz, B. Schmidt, R. Mankel, B. Giacobbe, Y. Bagaturia, R. Wurth, D. Pose, Y. Guilitsky, S. Prystupa, Wouter Hulsbergen, K. Ehret, M. Funcke, J. Kessler, Antonio Sbrizzi, S. J. Aplin, Helmut Wolters, B. Schwingenheuer, Farid Ould-Saada, T. Jagla, X. Dong, F. Khasanov, S. Masciocchi, T. Kvaratskheliia, J. Batista, M. Danilov, J. Pyrlik, R. Mizuk, O. Igonkina, M. zur Nedden, M. Poli, Kwong Lau, M. Starič, A. S. Schwarz, Alexander Spiridonov, U. Uwer, Valery Pugatch, D. Peralta, A. Zhelezov, M. Bruinsma, A. Somov, Kendall Reeves, Aleš Stanovnik, G. Medin, I. Vukotic, João Carvalho, H. Rick, H. Kapitza, T. Zeuner, Antonio Zoccoli, I. Massa, Vasco Amaral, A. Wurz, T. Hott, P. Conde, Igor Golutvin, Yu. Zaitsev, C. Cruse, M. A. Pleier, Th. Bauer, Sebastian Nowak, D. Wegener, H. Wahlberg, W. Gradl, C. Jiang, M. Bargiotti, M. T. Nunez Pardo de Vera, M. Agari, Ulrich Werthenbach, L. Sozuer, Maksym Titov, I. ABT, M. ADAMS, M. AGARI, H. ALBRECHT, A. ALEKSANDROV, V. AMARAL, A. AMORIM, S.J. APLIN, V. AUSHEV, Y. BAGATURIA, V. BALAGURA, M. BARGIOTTI, O. BARSUKOVA, J. BASTOS, J. BATISTA, C. BAUER, TH.S. BAUER, A. BELKOV, AR. BELKOV, I. BELOTELOV, A. BERTIN, B. BOBCHENKO, M. BOCKER, A. BOGATYREV, G. BOHM, M. BRAUER, M. BRUINSMA, M. BRUSCHI, P. BUCHHOLZ, T. BURAN, J. CARVALHO, P. CONDE, C. CRUSE, M. DAM, K.M. DANIELSEN, M. DANILOV, S. DE CASTRO, H. DEPPE, X. DONG, H.B. DREIS, V. EGORYTCHEV, K. EHRET, F. EISELE, D. EMELIYANOV, S. ESSENOV, L. FABBRI, P. FACCIOLI, M. FEUERSTACK-RAIBLE, J. FLAMMER, B. FOMINYKH, M. FUNCKE, LL. GARRIDO, A. GELLRICH, B. GIACOBBE, J. GLA), D. GOLOUBKOV, Y. GOLUBKOV, A. GOLUTVIN, I. GOLUTVIN, I. GORBOUNOV, A. GORISEK, O. GOUCHTCHINE, D.C. GOULART, S. GRADL, W. GRADL, F. GRIMALDI, J. GROTH-JENSEN, YU. GUILITSKY, J.D. HANSEN, J.M. HERNANDEZ, W. HOFMANN, M. HOHLMANN, T. HOTT, W. HULSBERGEN, U. HUSEMANN, O. IGONKINA, M. ISPIRYAN, T. JAGLA, C. JIANG, H. KAPITZA, S. KARABEKYAN, N. KARPENKO, S. KELLER, J. KESSLER, F. KHASANOV, YU. KIRYUSHIN, I. KISEL, E. KLINKBY, K.T. KNOPFLE, H. KOLANOSKI, S. KORPAR, C. KRAUSS, P. KREUZER, P. KRIZAN, D. KRUCKER, S. KUPPER, T. KVARATSKHELIIA, A. LANYOV, K. LAU, B. LEWENDEL, T. LOHSE, B. LOMONOSOV, R. MANNER, R. MANKEL, S. MASCIOCCHI, I. MASSA, I. MATCHIKHILIAN, G. MEDIN, M. MEDINNIS, M. MEVIUS, A. MICHETTI, YU. MIKHAILOV, R. MIZUK, R. MURESAN, M. ZUR NEDDEN, M. NEGODAEV, M. NORENBERG, S. NOWAK, M.T. NUNEZ PARDO DE VERA, M. OUCHRIF, F. OULD-SAADA, C. PADILLA, D. PERALTA, R. PERNACK, R. PESTOTNIK, B.A. PETERSEN, M. PICCININI, M.A. PLEIER, M. POLI, V. POPOV, D. POSE, S. PRYSTUPA, V. PUGATCH, Y. PYLYPCHENKO, J. PYRLIK, K. REEVES, D. RESSING, H. RICK, I. RIU, P. ROBMANN, I. ROSTOVTSEVA, V. RYBNIKOV, F. SANCHEZ, A. SBRIZZI, M. SCHMELLING, B. SCHMIDT, A. SCHREINER, H. SCHRODER, U. SCHWANKE, A.J. SCHWARTZ, A.S. SCHWARZ, B. SCHWENNINGER, B. SCHWINGENHEUER, F. SCIACCA, N. SEMPRINI-CESARI, S. SHUVALOV, L. SILVA, D. SKRK, L. SOZUER, S. SOLUNIN, A. SOMOV, S. SOMOV, J. SPENGLER, R. SPIGHI, A. SPIRIDONOV, A. STANOVNIK, M. STARIC, C. STEGMANN, H.S. SUBRAMANIA, M. SYMALLA, I. TIKHOMIROV, M. TITOV, I. TSAKOV, U. UWER, C. VAN ELDIK, YU. VASSILIEV, M. VILLA, A. VITALE, I. VUKOTIC, H. WAHLBERG, A.H. WALENTA, M. WALTER, J.J. WANG, D. WEGENER, U. WERTHENBACH, H. WOLTERS, R. WURTH, A. WURZ, S. XELLA-HANSEN, YU. ZAITSEV, M. ZAVERTYAEV, T. ZEUNER, A. ZHELEZOV, Z. ZHENG, R. ZIMMERMANN, T. ZIVKO, and A. ZOCCOLI

Subjects
Mass number, Physics, Particle physics, Physics and Astronomy (miscellaneous), Proton, Meson, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, HERA, 01 natural sciences, High Energy Physics - Experiment, Nuclear physics, symbols.namesake, 0103 physical sciences, symbols, Feynman diagram, ddc:530, High Energy Physics::Experiment, Rapidity, Nuclear Experiment, 010306 general physics, Engineering (miscellaneous), Storage ring, HERA-B
Abstract

The inclusive production cross sections of the charmed mesons D^0, D^+, D_s^+ and D^{*+} have been measured in interactions of 920 GeV protons on C, Ti, and W targets with the HERA-B detector at the HERA storage ring. Differential cross sections as a function of transverse momentum and Feynman's x variable are given for the central rapidity region and for transverse momenta up to $\pT=3.5$ GeV/$c$. The atomic mass number dependence and the leading to non-leading particle production asymmetries are presented as well., Comment: Submitted to EPJ C

Published
2007

213. Comparison of radon lung dosimetry models for the estimation of dose uncertainties

Author

Renate Winkler-Heil, Werner Hofmann, A. Birchall, and J. W. Marsh

Subjects
Two generation, chemistry.chemical_element, Radon, Radiation Dosage, Models, Biological, Sensitivity and Specificity, Statistics, Humans, Dosimetry, Computer Simulation, Radiology, Nuclear Medicine and imaging, Radiometry, Lung, Mathematics, Aerosols, Inhalation Exposure, Radiation, Radiological and Ultrasound Technology, business.industry, Public Health, Environmental and Occupational Health, Reproducibility of Results, General Medicine, chemistry, Organ Specificity, Radon Progeny, Nuclear medicine, business, Dose conversion
Abstract

In order to investigate the degree of dose uncertainty produced by different models, three dosimetry models were compared with each other, representing different classes of models: (i) The RADEP/IMBA model based on the ICRP Human Respiratory Tract Model, a deterministic regional compartment model, (ii) the RADOS model, a deterministic airway generation model and (iii) the IDEAL dosimetry model, a stochastic airway generation model. The outputs of the three models for defined mining exposure conditions were compared at three different levels: deposition fractions for attached and unattached radon progeny; nuclear transformations, reflecting the combined effect of deposition and clearance; and resulting cellular doses. Resulting dose exposure conversion factors ranged from 7.8 (median) mSv/WLM (IDEAL) to 11.8 mSv/WLM (RADEP/IMBA), with 8.3 mSv/WLM (RADOS) as an intermediate value. Despite methodological and computational differences between the three models, resulting dose conversion factors do not appreciably differ from each other, although predictions by the two generation models are consistently smaller than that for the RADEP/IMBA model.

Published
2007

214. Effect of inhomogeneous activity distributions and airway geometry on cellular doses in radon lung dosimetry

Author

Árpád Farkas, István Szőke, Werner Hofmann, and Imre Balásházy

Subjects
Materials science, chemistry.chemical_element, Linear energy transfer, Radon, Geometry, Radiation Dosage, Models, Biological, Sensitivity and Specificity, Humans, Deposition (phase transition), Dosimetry, Computer Simulation, Radiology, Nuclear Medicine and imaging, Nuclide, Radiometry, Lung, Bifurcation, Aerosols, Inhalation Exposure, Radiation, Radiological and Ultrasound Technology, Public Health, Environmental and Occupational Health, Reproducibility of Results, General Medicine, respiratory system, Ridge (differential geometry), respiratory tract diseases, Distribution (mathematics), chemistry, Organ Specificity, Anisotropy
Abstract

The human tracheobronchial system has a very complex structure including cylindrical airway ducts connected by airway bifurcation units. The deposition of the inhaled aerosols within the airways exhibits a very inhomogeneous pattern. The formation of deposition hot spots near the carinal ridge has been confirmed by experimental and computational fluid and particle dynamics (CFPD) methods. In spite of these observations, current radon lung dosimetry models apply infinitely long cylinders as models of the airway system and assume uniform deposition of the inhaled radon progenies along the airway walls. The aim of this study is to investigate the effect of airway geometry and non-uniform activity distributions within bronchial bifurcations on cellular dose distributions. In order to answer these questions, the nuclear doses of the bronchial epithelium were calculated in three different irradiation situations. (1) First, CFPD methods were applied to calculate the distribution of the deposited alpha-emitting nuclides in a numerically constructed idealised airway bifurcation. (2) Second, the deposited radionuclides were randomly distributed along the surface of the above-mentioned geometry. (3) Finally, calculations were made in cylindrical geometries corresponding to the parent and daughter branches of the bifurcation geometry assuming random nuclide activity distribution. In all three models, the same 218 Po and 214 Po surface activities per tissue volumes were assumed. Two conclusions can be drawn from this analysis: (i) average nuclear doses are very similar in all three cases (minor differences can be attributed to differences in the linear energy transfer (LET) spectra) and (ii) dose distributions are significantly different in all three cases, with the highest doses at the carinal ridge in case 3.

Published
2007

215. Internal microdosimetry of inhaled radon progeny in bronchial airways: advantages and limitations

Author

Werner Hofmann, Hatim Fakir, Pascal Pihet, University of Salzburg, and Institut de Radioprotection et de Sûreté Nucléaire (IRSN)

Subjects
aerosol, [SDV]Life Sciences [q-bio], 030218 nuclear medicine & medical imaging, 0302 clinical medicine, Models, carcinogenicity, Inhalation exposure, Inhalation Exposure, evaluation, Radiation, quantitative analysis, Radiological and Ultrasound Technology, Biological modeling, Low dose, article, radiation carcinogenesis, methodology, General Medicine, microdosimetry, Monte Carlo method, bioassay, Organ Specificity, Radon, Radon Progeny, 030220 oncology & carcinogenesis, radiation dose distribution, Biological Assay, radiation dose, Radiation response, radiation response, Radiation Carcinogenesis, chemistry.chemical_element, Bronchi, Dose distribution, Radiation Dosage, Models, Biological, Sensitivity and Specificity, 03 medical and health sciences, Humans, controlled study, Computer Simulation, Radiology, Nuclear Medicine and imaging, human, Radiometry, reproducibility, Aerosols, business.industry, antibody specificity, Public Health, Environmental and Occupational Health, Reproducibility of Results, bronchus, biological model, Biological, respiratory tract diseases, lung cancer, chemistry, exposure, alpha radiation, Nuclear medicine, business, metabolism, Biomedical engineering
Abstract

The objective of the present study was to identify advantages and limitations of the application of microdosimetric concepts for inhaled radon progeny activities in the lungs. The methods employed for this analysis were a recently developed Monte-Carlo microdosimetry code for the calculation of energy deposition in bronchial target cells and the Probability Per Unit Track Length (PPUTL) model, which relates these microdosimetric parameters to cellular radiation effects. The major advantages of internal microdosimetry of radon progeny in bronchial airways are: (i) quantitative characterisation of non-uniform dose distributions and identification of target sites with enhanced carcinogenic potential, (ii) quantification of low doses of alpha particles by the number of cells hit and the dose received by those cells, (iii) illustration of the random variations of cellular doses by specific energy distributions and (iv) establishment of a direct link to cellular radiobiological effects. At present, a major limitation of microdosimetry is the extrapolation of the response of individual cells to the resulting tissue response, which is still not fully explored. © The Author 2007. Published by Oxford University Press. All rights reserved.

Published
2007

216. Monte-Carlo-Modell der Aerosolbolusdispersion in der menschlichen Lunge – Teil 2: Modellvorhersagen für die kranke Lunge

Author

Robert Sturm, Werner Hofmann, and Ełzbieta Pawłak

Subjects
Chronic bronchitis, Lung, Radiological and Ultrasound Technology, business.industry, Biophysics, Healthy subjects, respiratory system, Airway obstruction, medicine.disease, Cystic fibrosis, Normal case, respiratory tract diseases, Bolus (medicine), medicine.anatomical_structure, Medicine, Radiology, Nuclear Medicine and imaging, Airway, business, Nuclear medicine
Abstract

After a mathematical extension of the existing model for the theoretical description of the aerosol bolus dispersion, the behavior of particle pulses in diseased lung structures was simulated. The geometry usedJbr healthy lungs was modified in two aspects: First, a modelling of possible airway obstructions, which usually occur in patients with chronic bronchitis, chronic asthma or cystic fibrosis, was carried out and, second, a theoretical approximation of the emphysema, being observed in lungs of smokers, but also as an accompanying phenomenon in obstructive diseases, was established. According to the modified model, in lungs with airway obstructions the exhaled bolus exhibited a decreased dispersion with respect to healthy subjects, whereas in emphysematous lungs the respective half-width of the peak was increased. Standard deviation and skewness of the bolus were similarly influenced by the modified lung architecture. A combination of airway obstruction and emphysema caused an extensive compensation of individual dispersion effects, complicating a secure distinction from the healthy lung. According to the model, a special diagnostic value may be assigned to the bolus deposition, showing significant deviations from the normal case for all simulated diseases.

Published
2007

217. Closing in on the gamma-ray sky

Author

Jim Hinton and Werner Hofmann

Subjects
Physics, Electromagnetic spectrum, media_common.quotation_subject, Gamma ray, Physics::Optics, General Physics and Astronomy, Astrophysics, Radiation, Wavelength, Sky, Octave, Closing (morphology), Microwave, media_common
Abstract

Over the last century our window on the universe has been widened by a staggering amount. From observations in the visible region of the electromagnetic spectrum, which spans one octave, astronomers have extended their view in two different directions. We are now able to study the cosmos in the long-wavelength radio and microwave regions right up to the ultrashort wavelengths of X-rays and gamma radiation – an increase of over 70 octaves. As many celestial objects and processes are only accessible at wavelengths beyond the optical range, this has provided us with a much more complete view of the universe.

Published
2007

218. Aerosol Drug Delivery Optimization by Computational Methods for the Characterization of Total and Regional Deposition of Therapeutic Aerosols in the Respiratory System

Author

István Szőke, B. Alföldy, Imre Balásházy, Andrea J. Molnar, Werner Hofmann, and Erika Kis

Subjects
Lung deposition, Chemistry, Nanotechnology, General Medicine, respiratory system, Aerosol, Deposition (aerosol physics), Drug Discovery, Drug delivery, Breathing, Molecular Medicine, Biochemical engineering, Respiratory system, Aerosol drug delivery
Abstract

The intake of medicines in form of aerosols is becoming increasingly popular, especially in the treatment of different lung diseases and allergies. In addition, there is a great interest to utilize the inhalation pathway for systemic therapy. Hence, determination of the required local distribution of inhaled therapeutic aerosols within the respiratory system is a key issue of modern aerosol drug design. In general, deposition characteristics of inhaled particles depend on the properties of the aerosols, the breathing mode and the geometry of the airways. All three parameters must be analyzed for the optimal design of therapeutic aerosols. A recommended way of drug inhalation may differ for various illnesses and patients. There are two different modeling directions for the description of deposition characteristics of inhaled drugs in the respiratory system. One way is the application of lung deposition models for the determination of total, regional and airway generation-specific deposition, and the other way is the usage of computational fluid dynamics techniques for the characterization of local deposition patterns, which, at present, cannot be applied to the whole respiratory system. This computational fluid dynamics approaches will be analyzed in another study. This work describes the general background of aerosol drug delivery optimization, summarizes previous important studies in the field, and provides a comprehensive discussion about numerical lung modeling and the salient features of the newest models and techniques. In the last part, the stochastic lung deposition model is applied to determine the optimal particle size and breathing technique for bronchial and pulmonary drug delivery.

Published
2007

219. 40 GHz Bandwidth and 64 GHz Resonance Frequency in Injection-Locked 1.55 $\mu$m VCSELs

Author

M.-C. Amann, Lukas Chrostowski, W.W. Chow, Werner Hofmann, B. Faraji, and Sebastian Wieczorek

Subjects
Frequency response, Materials science, business.industry, Bandwidth (signal processing), Physics::Optics, Rate equation, Laser, Atomic and Molecular Physics, and Optics, Semiconductor laser theory, law.invention, Vertical-cavity surface-emitting laser, Injection locking, Optics, law, Broadband, Optoelectronics, Electrical and Electronic Engineering, business
Abstract

Injection locking is shown to greatly enhance the resonance frequency of 1.55 mum vertical-cavity surface-emitting lasers (VCSELs), from 10 to 60 GHz, under ultrahigh injection locking conditions. Using injection locking to increase the laser resonance frequency, together with a low parasitic VCSEL design, a 3 dB bandwidth of over 40 GHz was attained, a record broadband performance for directly modulated VCSELs. VCSELs with slightly detuned polarization modes are injection locked with controlled polarization angles. For the first time, a dual-resonance frequency response is observed, and is explained with a two polarization-mode injection-locked rate equation model.

Published
2007

220. Results on $$\beta \beta $$ β β decay with emission of two neutrinos or Majorons in $$^{76}$$ 76 Ge from GERDA Phase I

Author

M. Shirchenko, I. V. Kirpichnikov, C. A. Ur, E. V. Demidova, N. Barros, Oliver Schulz, V. Egorov, E. Doroshkevich, Alberto Pullia, O. Fedorova, A. V. Veresnikova, A. Chernogorov, K. N. Gusev, Alessandro Bettini, Allen Caldwell, J. Janicskó Csáthy, R. Falkenstein, A. Kirsch, A. Garfagnini, Stefano Riboldi, D. Borowicz, N. Frodyma, S. Belogurov, E. Medinaceli, D. R. Zinatulina, M. Misiaszek, A. Domula, M. Balata, O.I. Kochetov, Stefan Schönert, D. Budjáš, C. Macolino, B. Lehnert, A. Wegmann, I. Zhitnikov, Igor Nemchenok, A. Hegai, P. Grabmayr, Cinzia Sada, Thomas Kihm, C. Schmitt, Matthias Laubenstein, Ivano Lippi, P. Zavarise, V.B. Brudanin, Hardy Simgen, Giovanni Benato, I. R. Barabanov, L. Vanhoefer, S. V. Zhukov, L. B. Bezrukov, M. Junker, V. Wagner, K. Panas, M. M. Wojcik, S. T. Belyaev, V. I. Gurentsov, Bela Majorovits, T. Bode, V. N. Kornoukhov, K. Pelczar, K. von Sturm, K. Freund, Luca Stanco, A. A. Vasenko, B. Schwingenheuer, Mikael Hult, A. M. Gangapshev, N. Becerici-Schmidt, M. Heisel, Laura Baudis, H. Wilsenach, S. Hemmer, M. Stepaniuk, Guillaume Lutter, A. M. Bakalyarov, M. Salathe, Manfred Lindner, H. Y. Liao, Christian Bauer, J. Schreiner, E. Bellotti, K. T. Knöpfle, A. Lubashevskiy, R. Brugnera, V. V. Kuzminov, Bayarto Lubsandorzhiev, Matteo Agostini, J. Jochum, P. Moseev, Luciano Pandola, A. A. Klimenko, T. Wester, N. Rumyantseva, A.A. Smolnikov, G. Zuzel, C. Cattadori, Kai Zuber, V. V. Kazalov, G. Heusser, Werner Hofmann, V. I. Lebedev, D. Palioselitis, M. Allardt, A. Lazzaro, O. Selivanenko, V. D'Andrea, W. Maneschg, E. A. Yanovich, L. V. Inzhechik, A. di Vacri, and Marc Walter

Subjects
Nuclear physics, Physics, Physics and Astronomy (miscellaneous), Phase (waves), Order (ring theory), Beta (velocity), Neutrino, Engineering (miscellaneous), Beta decay, Majoron, Semiconductor detector
Abstract

A search for neutrinoless $\beta\beta$ decay processes accompanied with Majoron emission has been performed using data collected during Phase I of the GERmanium Detector Array (GERDA) experiment at the Laboratori Nazionali del Gran Sasso of INFN (Italy). Processes with spectral indices n = 1, 2, 3, 7 were searched for. No signals were found and lower limits of the order of 10$^{23}$ yr on their half-lives were derived, yielding substantially improved results compared to previous experiments with $^{76}$Ge. A new result for the half-life of the neutrino-accompanied $\beta\beta$ decay of $^{76}$Ge with significantly reduced uncertainties is also given, resulting in $T^{2\nu}_{1/2} = (1.926 \pm 0.095)\cdot10^{21}$ yr.

Published
2015

221. Analyses of local dose distributions in the lungs for the determination of risk apportionment factors

Author

Lukas Pichelstorfer, Renate Winkler-Heil, Werner Hofmann, and M. Hussain

Subjects
Adult, Male, Veterinary medicine, chemistry.chemical_element, Radon, Dose distribution, Biology, Radiation Dosage, Models, Biological, Risk Assessment, chemistry.chemical_compound, Apportionment, Regional cancer, Administration, Inhalation, medicine, Animals, Humans, Radiology, Nuclear Medicine and imaging, Computer Simulation, Tissue Distribution, Lung cancer, Radiometry, Thorotrast, Lung, Radiation, Models, Statistical, Radiological and Ultrasound Technology, Inhalation, Public Health, Environmental and Occupational Health, Exhalation, Absorption, Radiation, General Medicine, Radiation Exposure, medicine.disease, respiratory tract diseases, Rats, chemistry, Air Pollutants, Radioactive, Air Pollution, Indoor
Abstract

For radiation protection purposes, the relative contributions of bronchial (BB), bronchiolar (bb) and alveolar-interstitial (AI) doses to lung cancer risk are represented by their corresponding apportionment factors. The current assumption of equal apportionment factors can be tested by comparing different radon and thoron progeny exposures, which produce different regional dose distributions, with the pathologically observed regional cancer distributions: (1) radon progeny inhalation, (2) thoron progeny inhalation, (3) thoron and thoron progeny exhalation (Thorotrast patients) and (4) RP inhalation in rats, and cigarette smoke inhalation as smoking is the dominant cause of lung cancer. Comparison with the pathologically observed regional cancer distributions suggests (1) a smaller apportionment factor for the AI region as compared with BB and bb regions and (2) a higher value for the BB region relative to that for the bb region.

Published
2015

222. From cellular doses to average lung dose

Author

Renate Winkler-Heil and Werner Hofmann

Subjects
Lung Neoplasms, Neoplasms, Radiation-Induced, Dose enhancement, Risk Assessment, Basal (phylogenetics), Cigarette smoking, Prevalence, Medicine, Background Radiation, Humans, Radiology, Nuclear Medicine and imaging, Air Pollution, Radioactive, Computer Simulation, Progenitor cell, Lung cancer, Radiation, Lung, Models, Statistical, Radiological and Ultrasound Technology, business.industry, Smoking, Public Health, Environmental and Occupational Health, General Medicine, respiratory system, Radiation Exposure, medicine.disease, respiratory tract diseases, medicine.anatomical_structure, Radon Progeny, Radon, Air Pollution, Indoor, Austria, Immunology, business, Airway
Abstract

Sensitive basal and secretory cells receive a wide range of doses in human bronchial and bronchiolar airways. Variations of cellular doses arise from the location of target cells in the bronchial epithelium of a given airway and the asymmetry and variability of airway dimensions of the lung among airways in a given airway generation and among bronchial and bronchiolar airway generations. To derive a single value for the average lung dose which can be related to epidemiologically observed lung cancer risk, appropriate weighting scenarios have to be applied. Potential biological weighting parameters are the relative frequency of target cells, the number of progenitor cells, the contribution of dose enhancement at airway bifurcations, the promotional effect of cigarette smoking and, finally, the application of appropriate regional apportionment factors. Depending on the choice of weighting parameters, detriment-weighted average lung doses can vary by a factor of up to 4 for given radon progeny exposure conditions.

Published
2015

223. Effect of Oral Pathway on Charged Particles Deposition in Human Bronchial Airways

Author

Khan Alam, Werner Hofmann, Renate Winker-Heil, Hussain Majid, and Pierre Madl

Subjects
Pulmonary and Respiratory Medicine, Pathology, medicine.medical_specialty, 010504 meteorology & atmospheric sciences, Inhalation, Chemistry, Pharmaceutical Science, Exhalation, Human airway, respiratory system, 030210 environmental & occupational health, 01 natural sciences, Charged particle, respiratory tract diseases, 03 medical and health sciences, 0302 clinical medicine, medicine, Biophysics, Pharmacology (medical), Deposition (chemistry), 0105 earth and related environmental sciences
Abstract

In vitro studies to investigate the effect of charged particle deposition in the oral pathway of human adults have demonstrated substantial increases in deposition due to an induced charge effect. In the current study, charged particle deposition in the oral pathway was incorporated in the stochastic human airway generation model IDEAL (Inhalation, Deposition, and Exhalation of Aerosols in the Lung) to quantify their effect on bronchial airways deposition.Calculation of increased oral deposition due to charged particles was performed by a modified version of IDEAL for oral pathway, whereas deposition in the bronchial airways was carried out by the already employed efficiency equation. Deposition calculations were performed for 3, 4.5, and 6 μm particles at flow rates of 15 and 30 L/min.The enhancement in deposition is found to be 40 times higher in oral pathway and 6 times higher in bronchial airways for 3 μm size particles carrying 2500 elementary charges. For particles larger than 3 μm, deposition by impaction dominates over deposition by particle charges, and hence higher deposition in oral pathway is observed primarily due to impaction. As a consequence of this increased oral deposition, bronchial airways deposition decreases.By controlling breathing, aerosol properties, and electrostatic charge, targeted deposition in the human airways can be improved. Hence, charged particles can therefore be utilized to give better control on regional drug delivery in the lungs or to filter out toxic constituents.

Published
2015

224. Production, characterization and operation of $$^{76}$$ 76 Ge enriched BEGe detectors in GERDA

Author

Laura Baudis, Matthias Laubenstein, W. Hampel, E. V. Demidova, E. Bellotti, P. Zavarise, H. Y. Liao, V. Wagner, L. B. Bezrukov, E. Shevchik, G. Pessina, A. A. Vasenko, J. Jochum, Thomas Kihm, K. N. Gusev, C. Gotti, Oliver Schulz, Stefan Schönert, Alberto Pullia, D. Budjáš, V. I. Lebedev, A. Garfagnini, K. Freund, C. Macolino, H. Strecker, Marcin Wójcik, P. Grabmayr, D. Palioselitis, N. Becerici-Schmidt, J. Janicskó Csáthy, B. Schwingenheuer, T. Wester, S. Belogurov, A.A. Smolnikov, E. Andreotti, B. Lehnert, C. Cattadori, Kai Zuber, H. Wilsenach, I. Zhitnikov, Alessandro Bettini, R. Brugnera, A. Kirsch, L. V. Inzhechik, A. Wegmann, Ivano Lippi, D. Borowicz, Igor Nemchenok, Luca Stanco, Manfred Lindner, Marc Walter, V. V. Kuzminov, Bela Majorovits, I. R. Barabanov, C. Schmitt, Matteo Agostini, Stefano Riboldi, S. V. Zhukov, K. T. Knöpfle, M. Salathe, M. Misiaszek, M. Shirchenko, G. Zuzel, M. Balata, C. O'Shaughnessy, L. Vanhoefer, T. Bode, Luciano Pandola, V. V. Kazalov, Christian Bauer, A. A. Klimenko, A. Lubashevskiy, N. Rumyantseva, A. Hegai, M. Allardt, N. Barros, V. Egorov, D. R. Zinatulina, A. Chernogorov, I. V. Kirpichnikov, Mikael Hult, C. A. Ur, S. Hemmer, O.I. Kochetov, S. T. Belyaev, J. Schreiner, A. M. Gangapshev, Cinzia Sada, Giovanni Benato, M. Junker, V. D'Andrea, A. Lazzaro, G. Heusser, A. Domula, R. Falkenstein, Werner Hofmann, V. I. Gurentsov, V.B. Brudanin, L. Ioannucci, Hardy Simgen, M. Heisel, Bayarto Lubsandorzhiev, K. von Sturm, A. Caldwel, V. N. Kornoukhov, K. Pelczar, Guillaume Lutter, A. M. Bakalyarov, W. Maneschg, N. Frodyma, E. A. Yanovich, and Stefano Nisi

Subjects
Physics, Cryostat, Physics and Astronomy (miscellaneous), Physics::Instrumentation and Detectors, 010308 nuclear & particles physics, Detector, chemistry.chemical_element, Cosmic ray, Germanium, 7. Clean energy, 01 natural sciences, Semiconductor detector, Nuclear physics, chemistry, Double beta decay, 0103 physical sciences, High Energy Physics::Experiment, Nuclear Experiment, 010306 general physics, Engineering (miscellaneous), Energy (signal processing), Diode
Abstract

The GERmanium Detector Array (GERDA) at the Gran Sasso Underground Laboratory (LNGS) searches for the neutrinoless double beta decay (0{\nu}{\beta}{\beta}) of $^{76}$Ge. Germanium detectors made of material with an enriched $^{76}$Ge fraction act simultaneously as sources and detectors for this decay. During Phase I of the experiment mainly refurbished semi-coaxial Ge detectors from former experiments were used. For the upcoming Phase II, 30 new $^{76}$Ge enriched detectors of broad energy germanium (BEGe)-type were produced. A subgroup of these detectors has already been deployed in GERDA during Phase I. The present paper reviews the complete production chain of these BEGe detectors including isotopic enrichment, purification, crystal growth and diode production. The efforts in optimizing the mass yield and in minimizing the exposure of the $^{76}$Ge enriched germanium to cosmic radiation during processing are described. Furthermore, characterization measurements in vacuum cryostats of the first subgroup of seven BEGe detectors and their long-term behavior in liquid argon are discussed. The detector performance fulfills the requirements needed for the physics goals of GERDA Phase~II.

Published
2015

225. [Assessment II: settings, systematics and tools]

Author

Werner Hofmann, S. Krupp, and U. Sommeregger

Subjects
Systematics, Aged, 80 and over, Male, Health (social science), Psychometrics, business.industry, Data science, Risk Assessment, United States, Issues, ethics and legal aspects, Germany, Surveys and Questionnaires, Medicine, Humans, Female, Geriatrics and Gerontology, business, Gerontology, Geriatric Assessment, Aged
Published
2015

226. The exceptionally powerful TeV gamma-ray emitters in the Large Magellanic Cloud

Author

J.-P. Lenain, A. Foerster, S. Krakau, F. Schüssler, Jim Hinton, Andrew M. Taylor, Julien Lefaucheur, Alison Mitchell, Matthias Weidinger, A. Djannati-Ataï, D. Klochkov, Martin Ward, Nu. Komin, M. Panter, M. Renaud, Alicja Wierzcholska, T. Garrigoux, Ignasi Reichardt, A. A. Zdziarski, S. Rosier-Lees, S. Schwarzburg, S. Balenderan, Markus Holler, Felix Jankowsky, M. Mohamed, Felix Aharonian, J. Becker-Tjus, H. Laffon, J. Mehault, L. O’C. Drury, U. Katz, P. Espigat, Chia-Chun Lu, K. Valerius, F. Krayzel, Igor Oya, J. Dyks, Francois Brun, Riaan Steenkamp, Werner Hofmann, M. Chrétien, G. Heinzelmann, N. Maxted, Tanya Edwards, Helen Poon, M. Füßling, C. B. Rulten V. Sahakian, Faical Ait Benkhali, Svenja Carrigan, A. Lopatin, Y. A. Gallant, H.-S. Zechlin, D. Gottschall, Anne Lemiere, M. J. Vorster, E. Birsin, Sarah Kaufmann, M. Gajdus, K. Kosack, Konrad Bernlöhr, R. C. G. Chaves, S. J. Nolan, Pascal Vincent, G. Pühlhofer, Axel Donath, D. Kolitzus, R. D. Parsons, G. Pelletier, S. Bernhard, Christian Stegmann, M. Mayer, J. Perez, A. Reimer, Johan Bregeon, K. Morå, Christo Venter, B. van Soelen, M. Kieffer, M. Zacharias, O. Hervet, Robert Wagner, Joachim Hahn, Mateusz Janiak, I. Jung, B. Rudak, Kathrin Egberts, Thomas Lohse, A. G. Akhperjanian, M. V. Fernandes, Andreas Quirrenbach, B. Degrange, A. Marcowith, S. Schwemmer, Andrea Santangelo, Gianluca Giavitto, Jacek Niemiec, C. Jahn, Michael Punch, P.P. Krüger, A. Wörnlein, S. Häffner, M. Ostrowski, A. Ivascenko, Jacco Vink, Peter Eger, S. J. Fegan, R. Moderski, Aion Viana, Sabrina Casanova, Olaf Reimer, Guillaume Dubus, H. J. Voelk, Denis Wouters, A. Zech, U. Schwanke, Frank M. Rieger, P. M. Chadwick, Krzysztof Katarzynski, Gilles Maurin, Catherine Boisson, Vincent Marandon, B. Opitz, M.-H. Grondin, Markus Böttcher, Reinhard Schlickeiser, Pol Bordas, P.-O. Petrucci, David Berge, David Sánchez, M. Grudzińska, N. W. Pekeur, Gavin Rowell, M. Bryan, D. Zaborov, R. de los Reyes, André Schulz, M. S. Meyer, C. Romoli, H. Odaka, M. Dalton, L. B. Oakes, E. O. Angüner, Johannes Veh, Thomas Murach, S. Colafrancesco, Dieter Horns, Michael Backes, Quirin Weitzel, J. Bolmont, C. Farnier, W. Kluźniak, M. Tluczykont, G. Spengler, Victor Zabalza, Daniela Hadasch, U. Menzler, B. Khélifi, G. Hermann, L. Rob, V. Lefranc, D. Fernandez, T. J. L. McComb, Andreas Hillert, M. A. Kastendieck, G. Vasileiadis, K. Dutson, F. Spies, P. Brun, C. Trichard, I. D. Davids, P. de Wilt, P. J. Meintjes, Gilles Henri, Y. Cui, C. Couturier, David Salek, E. Moulin, Tomasz Bulik, A. Jacholkowska, B. Peyaud, W. Domainko, R. White, A. Balzer, Christoph Deil, Felix Spanier, S. Klepser, Nachiketa Chakraborty, M. Lemoine-Goumard, R. Chalme-Calvet, P. Wagner, J.-P. Tavernet, Francesca Volpe, G. Lamanna, Jan Conrad, F. Stinzing, B. Giebels, G. Fontaine, Ramin Marx, A. Fiasson, T. Vuillaume, S. J. Wagner, P. Willmann, K. Stycz, Michal Dyrda, J. F. Glicenstein, M. de Naurois, Ruizhi Yang, Thomas Tavernier, Yvonne Becherini, Petter Hofverberg, F. Feinstein, Marek Jamrozy, Stefan Ohm, Helene Sol, S. Pita, J. Harris, Stefano Gabici, Regis Terrier, Ł. Stawarz, I. Sushch, S. Raab, A. Abramowski, M. Paz Arribas, J. Biteau, A. Barnacka, G. Cologna, C. van Eldik, H.E.S.S. Collaboration, Département de Physique des Particules (ex SPP) (DPP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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), Département d'Astrophysique (ex SAP) (DAP), HESS, Département de Physique des Particules (ex SPP) (DPhP), and High Energy Astrophys. & Astropart. Phys (API, FNWI)

Subjects
Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Superbubble, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Pulsar wind nebula, Pulsar, 0103 physical sciences, Satellite galaxy, Astrophysics::Solar and Stellar Astrophysics, Large Magellanic Cloud, Supernova remnant, HESS - Abteilung Hofmann, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Multidisciplinary, 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Institut für Physik und Astronomie, Astronomy, Galaxy, Supernova, ddc:500, Astrophysics - High Energy Astrophysical Phenomena
Abstract

The Large Magellanic Cloud, a satellite galaxy of the Milky Way, has been observed with the High Energy Stereoscopic System (H.E.S.S.) above an energy of 100 billion electron volts for a deep exposure of 210 hours. Three sources of different types were detected: the pulsar wind nebula of the most energetic pulsar known N 157B, the radio-loud supernova remnant N 132D and the largest non-thermal X-ray shell - the superbubble 30 Dor C. The unique object SN 1987A is, surprisingly, not detected, which constrains the theoretical framework of particle acceleration in very young supernova remnants. These detections reveal the most energetic tip of a gamma-ray source population in an external galaxy, and provide via 30 Dor C the unambiguous detection of gamma-ray emission from a superbubble., Published in Science Magazine (Jan. 23, 2015). This ArXiv version has the supplementary online material incorporated as an appendix to the main paper

Published
2015

228. Cross Calibration of Telescope Optical Throughput Efficiencies using Reconstructed Shower Energies for the Cherenkov Telescope Array

Author

Konrad Bernlöhr, Alison Mitchell, Werner Hofmann, and R. D. Parsons

Subjects
Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, IACT, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, law.invention, Telescope, Optics, law, 0103 physical sciences, Calibration, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Throughput (business), Instrumentation and Methods for Astrophysics (astro-ph.IM), Cherenkov radiation, Event reconstruction, Physics, 010308 nuclear & particles physics, business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Gamma-ray astronomy, Cherenkov Telescope Array, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, business
Abstract

For reliable event reconstruction of Imaging Atmospheric Cherenkov Telescopes (IACTs), calibration of the optical throughput efficiency is required. Within current facilities, this is achieved through the use of ring shaped images generated by muons. Here, a complementary approach is explored, achieving cross calibration of elements of IACT arrays through pairwise comparisons between telescopes, focussing on its applicability to the upcoming Cherenkov Telescope Array (CTA). Intercalibration of telescopes of a particular type using eventwise comparisons of shower image amplitudes has previously been demonstrated to recover the relative telescope optical responses. A method utilising the reconstructed energy as an alternative to image amplitude is presented, enabling cross calibration between telescopes of varying types within an IACT array. Monte Carlo studies for two plausible CTA layouts have shown that this calibration procedure recovers the relative telescope response efficiencies at the few percent level., Comment: 8 pages, 4 figures, accepted for publication in Astroparticle Physics

Published
2015
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229. Improvement of the energy resolution via an optimized digital signal processing in GERDA Phase I

Author

M. Shirchenko, D. Palioselitis, Laura Baudis, I. V. Kirpichnikov, J. Janicskó Csáthy, I. Zhitnikov, Oliver Schulz, H. Y. Liao, W. Maneschg, E. A. Yanovich, N. Barros, Alberto Pullia, J. Jochum, V. N. Kornoukhov, K. Pelczar, A. Garfagnini, L. V. Inzhechik, A.-K. Schütz, A. Hegai, C. Macolino, V. I. Gurentsov, Manfred Lindner, V. V. Kazalov, Allen Caldwell, A. V. Veresnikova, A. Wegmann, Igor Nemchenok, Marc Walter, Guillaume Lutter, A. M. Bakalyarov, V. I. Lebedev, M. Heisel, Bayarto Lubsandorzhiev, A. Chernogorov, T. Wester, B. Lehnert, O. Fedorova, A.A. Smolnikov, Bela Majorovits, K. von Sturm, C. Cattadori, Matthias Laubenstein, P. Zavarise, Kai Zuber, M. Balata, N. Frodyma, R. Brugnera, O. Selivanenko, D. Budjáš, V. Egorov, V. Wagner, K. N. Gusev, E. V. Demidova, L. Vanhoefer, V. V. Kuzminov, Matteo Agostini, T. Bode, Ivano Lippi, A. di Vacri, O.I. Kochetov, Werner Hofmann, E. Bellotti, M. Allardt, A. A. Vasenko, E. Doroshkevich, L. B. Bezrukov, E. Medinaceli, Stefan Schönert, Christian Bauer, S. T. Belyaev, K. Freund, A. Lubashevskiy, A. M. Gangapshev, S. Belogurov, M. Salathe, B. Schwingenheuer, R. Falkenstein, Cinzia Sada, C. Schmitt, Giovanni Benato, Stefano Riboldi, Thomas Kihm, D. R. Zinatulina, C. A. Ur, A. Domula, P. Moseev, G. Heusser, Luciano Pandola, M. Misiaszek, A. A. Klimenko, Marcin Wójcik, P. Grabmayr, N. Rumyantseva, Alessandro Bettini, V.B. Brudanin, A. Kirsch, Hardy Simgen, Mikael Hult, S. Hemmer, J. Schreiner, B. Schneider, I. R. Barabanov, S. V. Zhukov, N. Becerici-Schmidt, H. Wilsenach, M. Stepaniuk, K. Panas, D. Borowicz, Luca Stanco, K. T. Knöpfle, G. Zuzel, V. D'Andrea, A. Lazzaro, and M. Junker

Subjects
Physics - Instrumentation and Detectors, Physics and Astronomy (miscellaneous), Isotopes of germanium, Q value, Physics::Instrumentation and Detectors, Phase (waves), FOS: Physical sciences, GERMANIUM DETECTORS, 01 natural sciences, Noise (electronics), Particle detector, GERDA - Abteilung Hofmann, Nuclear physics, Nuclear magnetic resonance, Double beta decay, 0103 physical sciences, CHARGE MEASUREMENTS, Nuclear Experiment (nucl-ex), 010306 general physics, SILICON, Engineering (miscellaneous), Nuclear Experiment, Physics, 010308 nuclear & particles physics, Instrumentation and Detectors (physics.ins-det), MINIMUM-NOISE, GENIUS, GE-76, DECAY, PROJECT, Radioactive decay, Energy (signal processing), OPTIMUM FILTERS
Abstract

An optimized digital shaping filter has been developed for the GERDA experiment which searches for neutrinoless double beta decay in 76Ge. The GERDA Phase I energy calibration data have been reprocessed and an average improvement of 0.3 keV in energy resolution (FWHM) at the 76Ge Q value for 0\nu\beta\beta decay is obtained. This is possible thanks to the enhanced low-frequency noise rejection of this Zero Area Cusp (ZAC) signal shaping fillter., Comment: 12 pages, 16 figures

Published
2015

230. Discovery of the VHE gamma-ray source HESS J1832-093 in the vicinity of SNR G22.7-0.2

Author

Julien Lefaucheur, J. Biteau, Matteo Cerruti, M. Holler, Matthias Weidinger, F. Krayzel, Tanya Edwards, M. Paz Arribas, Christo Venter, Dirk Lennarz, K. Dutson, F. Spies, Mateusz Janiak, Alexandre Marcowith, C. Jahn, S. Raab, A. Abramowski, C. L. Naumann, R. C. G. Chaves, M. K. Daniel, C. Stegmann, U. F. Katz, R. Moderski, A. Zech, Frank M. Rieger, Gilles Henri, G. Fontaine, Ullrich Schwanke, Iurii Sushch, Werner Hofmann, P. M. Chadwick, Nu. Komin, S. Krakau, Pierre-Olivier Petrucci, A. Fiasson, S. Häffner, Pierre Brun, Ramin Marx, M. Mohamed, A. G. Akhperjanian, Christoph Deil, M. Kieffer, Denis Wouters, T. Kneiske, Stefan Ohm, Aion Viana, V. Sahakian, M. de Naurois, Martin Ward, Jim Hinton, P. Willmann, S. Pita, F. Stinzing, Michal Dyrda, R. Steenkamp, F. Ait Benkhali, S. Schwemmer, B. Opitz, B. Giebels, S. Schwarzburg, Cameron B Rulten, L. O'c. Drury, P. deWilt, E. de Oña Wilhelmi, W. Kluźniak, Sarah Kaufmann, K. Katarzyński, S. J. Nolan, S. Balenderan, S. Klepser, A. C. Clapson, Joachim Hahn, Andrea Santangelo, S. Colafrancesco, Guillaume Dubus, C. Couturier, L. Oakes, M. Tluczykont, Marek Jamrozy, J. Dyks, Andreas Quirrenbach, Łukasz Stawarz, Felix Aharonian, Manuel Meyer, Michael Zacharias, Heinrich J. Völk, Stefan Wagner, Gisela Anton, M. Mayer, Helene Sol, J. Brucker, P.P. Krüger, K. Valerius, R. Chalme-Calvet, M. Panter, R. D. Parsons, J. Harris, Quirin Weitzel, A. Cheesebrough, M. Gajdus, C. Romoli, L. Rob, Elisabetta Bissaldi, Daniel Sánchez, Konrad Bernlöhr, Jan Conrad, K. Stycz, P. Vincent, M. J. Vorster, J. F. Glicenstein, Tomasz Bulik, D. Fernandez, Vincent Marandon, Victor Zabalza, U. Menzler, Gianluca Giavitto, G. Cologna, C. van Eldik, B. van Soelen, I. Jung, B. Rudak, Kathrin Egberts, M. A. Kastendieck, B. Degrange, I. D. Davids, G. Pühlhofer, Markus Böttcher, G. Spengler, M. Füßling, G. Vasileiadis, J. Perez, Y. Cui, Karl Kosack, A. Jacholkowska, A. Reimer, Catherine Boisson, Felix Jankowsky, Fabio Acero, T. J. L. McComb, S. Rosier-Lees, H. Laffon, Andreas Hillert, J. Becker Tjus, T. Vuillaume, Michał Ostrowski, G. Lamanna, W. Domainko, M. Renaud, A. Balzer, M. V. Fernandes, Sabrina Casanova, B. Peyaud, Y. A. Gallant, H.-S. Zechlin, R. White, C. Trichard, Thomas Lohse, A. Wörnlein, M. Grudzińska, P. J. Meintjes, Francois Brun, M. Chrétien, Chia-Chun Lu, Anna Zajczyk, N. W. Pekeur, D. Kolitzus, M. Dalton, Gavin Rowell, A. Djannati-Ataï, Peter Eger, P. Wagner, Guy Pelletier, A. Förster, R. de los Reyes, C. Farnier, Martin Raue, Andrew M. Taylor, B. Khélifi, G. Hermann, Regis Terrier, F. Schüssler, T. Garrigoux, O. Hervet, P. Espigat, D. Klochkov, Marianne Lemoine-Goumard, I. Oya, Jacek Niemiec, A. Lemière, Olaf Reimer, Michael Punch, N. Maxted, Anna Szostek, S. J. Fegan, Thomas Murach, Svenja Carrigan, E. Birsin, Petter Hofverberg, Emmanuel Moulin, André Schulz, J. Méhault, F. Feinstein, Dieter Horns, A. A. Zdziarski, J.-P. Tavernet, Yvonne Becherini, G. Maurin, M. H. Grondin, Francesca Volpe, Helen Poon, A. Lopatin, J.-P. Lenain, Reinhard Schlickeiser, Pol Bordas, Hugh Dickinson, E. O. Angüner, G. Heinzelmann, J. Bolmont, Anna Barnacka, Alicja Wierzcholska, T. Tavernier, Institut für Experimentalphysik [Hamburg], Universität Hamburg (UHH), CEA- Saclay (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Max Planck Institute for Nuclear Physics (MPIK), Max-Planck-Gesellschaft, Dublin Institute for Advanced Studies (DIAS), National Academy of Sciences of the Republic of Armenia [Yerevan] (NAS RA), Humboldt-Universität zu Berlin, Physikalisches Institut [Erlangen], Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Department of Physics [Durham], University of New Hampshire (UNH), Deutsches Elektronen-Synchrotron [Zeuthen] (DESY), Helmholtz-Gemeinschaft = Helmholtz Association, Universität Potsdam, Astronomical Observatory [Warsaw], Faculty of Physics [Warsaw] (FUW), University of Warsaw (UW)-University of Warsaw (UW), Linnaeus University, Institut für Theoretische Physik IV [Bochum] (ITP4), Ruhr-Universität Bochum [Bochum], Institut f¨ur Astro- und Teilchenphysik and Institut f¨ur Theoretische Physik, Leopold-Franzens Universitat Innsbruck, 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), North-West University [South Aftrica] (NWU), Laboratoire Univers et Théories (LUTH (UMR_8102)), Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - 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), Institut für Astronomie und Astrophysik [Tübingen] (IAAT), Eberhard Karls Universität Tübingen = Eberhard Karls University of Tuebingen, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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), Harvard-Smithsonian Center for Astrophysics (CfA), Smithsonian Institution-Harvard University [Cambridge], University of the Witwatersrand [Johannesburg] (WITS), Landessternwarte Königstuhl [ZAH] (LSW), Universität Heidelberg [Heidelberg], Stockholm University, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Namibia University of Science and Technology (NUST), University of Adelaide, Oskar Klein Centre [Stockholm], 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), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Department of Physics and Astronomy [Leicester], University of Leicester, Instytut Fizyki Jądrowej PAN (IFJ), Polskiej Akademii Nauk, Laboratoire Univers et Particules de Montpellier (LUPM), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2), 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), Institut für Physik und Astrophysik [Potsdam], Obserwatorium Astronomiczne, Uniwersytet Jagiello?ski, Torun Centre for Astronomy (TCfA), Nicolaus Copernicus University [Toruń], University of the Free State [South Africa], Université Pierre et Marie Curie - Paris 6 - UFR de Médecine Pierre et Marie Curie (UPMC), Université Pierre et Marie Curie - Paris 6 (UPMC), Astronomical Observatory [Kraków], Uniwersytet Jagielloński w Krakowie = Jagiellonian University (UJ), Institut für Experimentalphysik [Innsbruck], Universität Innsbruck [Innsbruck], Institute of Astronomy [Prague], Charles University [Prague] (CU), HESS, H.E.S.S. Collaboration, Humboldt University Of Berlin, University of Potsdam = Universität Potsdam, 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)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), 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 Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Harvard University-Smithsonian Institution, Universität Heidelberg [Heidelberg] = Heidelberg University, Université Sciences et Technologies - Bordeaux 1 (UB)-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)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), University of the Free State [South Africa] (UFS), 24420530 - Böttcher, Markus, 23909196 - Casanova, Sabrina, 13146629 - Davids, Isak Delberth, 11749903 - Krüger, Petrus Paulus, 22050574 - Pekeur, Nicolette Whilna, 24922986 - Sushch, Iurii, 12006653 - Venter, Christo, and 12792322 - Vorster, Michael Johannes

Subjects
Photon, ISM: individual objects: HESS J1832−093, Point source, Astrophysics::High Energy Astrophysical Phenomena, Hochenergie-Astrophysik Theorie - Abteilung Hofmann, Gamma rays: general, FOS: Physical sciences, Cosmic ray, Astrophysics, individual objects: HESS J1832−093 [ISM], Pulsar wind nebula, general. [Gamma-rays], Astroparticle physics, Gamma-rays: general, ISM: individual objects: HESS J1832-093, ISM: individual objects: SNR G22.7-0.2, Astronomy and Astrophysics, Space and Planetary Science, individual objects: SNR G22.7−0.2 [ISM], Supernova remnant, HESS - Abteilung Hofmann, Astrophysics::Galaxy Astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Molecular cloud, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Gamma ray, Institut für Physik und Astronomie, Astronomy, ddc:520, High Energy Physics::Experiment, ISM: individual objects: SNR G22.7−0.2, Astrophysics - High Energy Astrophysical Phenomena, general [gamma-rays]
Abstract

Monthly notices of the Royal Astronomical Society 446(2), 1163 - 1169 (2015). doi:10.1093/mnras/stu2148, The region around the supernova remnant (SNR) W41 contains several TeV sources and has prompted the HESS Collaboration to perform deep observations of this field of view. This resulted in the discovery of the new very high energy (VHE) source HESS J1832−093, at the position $RA=18^{h}32^{m}50^{s} \pm 3^{s}_{stat}\pm2^{s}_{syst},Dec=−9^\circ22^{\prime} 36^{\prime\prime} \pm 32^{\prime\prime}_{stat} \pm 20^{\prime\prime}_{syst}(J2000)$, spatially coincident with a part of the radio shell of the neighbouring remnant G22.7−0.2. The photon spectrum is well described by a power law of index Γ = 2.6 $\pm$ 0.3$_{stat}$ $\pm$ 0.1$_{syst}$ and a normalization at 1 TeV of Φ$_{0}=(4.8 \pm 0.8_{stat} \pm 1.0_{syst}) ×10^{−13}cm^{−2}s^{−1}TeV^{−1}$. The location of the gamma-ray emission on the edge of the SNR rim first suggested a signature of escaping cosmic rays illuminating a nearby molecular cloud. Then a dedicated XMM–Newton observation led to the discovery of a new X-ray point source spatially coincident with the TeV excess. Two other scenarios were hence proposed to identify the nature of HESS J1832−093. Gamma-rays from inverse Compton radiation in the framework of a pulsar wind nebula scenario or the possibility of gamma-ray production within a binary system are therefore also considered. Deeper multiwavelength observations will help to shed new light on this intriguing VHE source., Published by Oxford Univ. Press, Oxford

Published
2015

231. Limit on Neutrinoless Double Beta Decay of 76Ge by GERDA

Author

A. Kirsch, W. Maneschg, E. A. Yanovich, Stefano Nisi, P. Zavarise, Josef Jochum, A. Domula, V. Wagner, J. Janicskó Csáthy, M. Salathe, Manfred Lindner, A. A. Vasenko, V. I. Gurentsov, I. Zhitnikov, L. Stanco, B. Lehnert, V.B. Brudanin, O. Volynets, Hardy Simgen, A. D. Ferella, M. Barabè Heider, D. R. Zinatulina, Ivano Lippi, Bayarto Lubsandorzhiev, A. Hegai, O.I. Kochetov, A. Wegmann, A. Lubashevskiy, Igor Nemchenok, A. Garfagnini, Claudio Gotti, S. T. Belyaev, C. Bauer, C. Macolino, A. Chernogorov, Allen Caldwell, Bela Majorovits, L. V. Inzhechik, A. M. Gangapshev, Stefano Riboldi, C.O’. Shaughnessy, P. Grabmayr, R. Brugnera, V. V. Kuzminov, Matteo Agostini, K. Freund, M. Misiaszek, V. I. Lebedev, W. Hampel, E. V. Demidova, K. K. Guthikonda, V. G. Egorov, I. V. Kirpichnikov, B. Schwingenheuer, Mikael Hult, M. Shirchenko, M. Allardt, K. von Sturm, M. Balata, H. Strecker, C. A. Ur, G. Heusser, Alessandro Bettini, K. N. Gusev, S. Belogurov, N. Frodyma, N. Barros, E. Andreotti, T. Bode, A. Lazzaro, Werner Hofmann, K. T. Knöpfle, G. Zuzel, O. Schulz, S. Schönert, S. Hemmer, T. Wester, A.A. Smolnikov, C. Cattadori, Kai Zuber, Laura Baudis, L. B. Bezrukov, E. Shevchik, H. Y. Liao, G. Pessina, M. M. Wojcik, A. A. Machado, F. Cossavella, D. Budjáš, E. Bellotti, M. Tarka, R. Falkenstein, Thomas Kihm, Jochen Schreiner, C. Schmitt, V. N. Kornoukhov, K. Pelczar, Guillaume Lutter, A. M. Bakalyarov, I. R. Barabanov, M. Walter, S. V. Zhukov, M. Laubenstein, Luciano Pandola, N. Becerici-Schmidt, A. A. Klimenko, M. Heisel, N. Rumyantseva, A. Pullia, Cinzia Sada, Giovanni Benato, and M. Junker

Subjects
Physics, Nuclear physics, Particle physics, Isotope, Double beta decay, SEARCH, double beta decay, Limit (mathematics), Physics and Astronomy(all), 0-NU-BETA-BETA DECAY, Semiconductor detector
Abstract

The Gerda experiment at the Laboratori Nazionali del Gran Sasso in Italy uses germanium detectors made from material with an enriched 76Ge isotope fraction to search for neutrinoless double beta decay of this nucleus. Applying a blind analysis we find no signal after an exposure of 21.6 kg·yr and a background of about 0.01 cts/(keV·kg·yr). A half-life limit of Tov1/2> 2.1 · 1025 yr (90% C.L.) is extracted. The previous claim of a signal for 76Ge is excluded with 99% probability in a model independent way.

Published
2015

233. Status of the Germanium Detector Array (GERDA) in the search of neutrinoless ββ decays of 76Ge at LNGS

Author

K. N. Gusev, S. Katulina, K. T. Knöpfle, P. Peiffer, V. N. Kornoukhov, A. V. Tikhomirov, I. Abt, V. G. Egorov, I. V. Kirpichnikov, Gerd Marissens, F. Stelzer, A. M. Bakalyarov, O.I. Kochetov, O. Chkvorets, M. Altmann, W. Hampel, E. V. Demidova, M. Junker, Josef Jochum, F. Zocca, D. Weißhaar, V. I. Lebedev, E. Farnea, Jochen Schreiner, V. I. Gurentsov, I. R. Barabanov, S. Scholl, M. M. Wojcik, G. Heusser, S. V. Zhukov, Kevin Kröninger, M. Bauer, S. T. Belyaev, A. M. Gangapshev, X. Liu, S. Belogurov, A.A. Smolnikov, G. Zuzel, E. Bellotti, C. Cattadori, C. R. Alvarez, V. P. Bolotsky, J. Kiko, L. B. Bezrukov, A. di Vacri, L. V. Inzhechik, Werner Hofmann, G. Y. Grigoriev, J. Yurkowski, J. Eberth, Igor Nemchenok, Allen Caldwell, V. B. Brudanin, Luciano Pandola, Bela Majorovits, Mikael Hult, M. Knapp, U. Schwan, A. A. Klimenko, S. Schönert, C. Bauer, E. A. Yanovich, M. Heisel, V. G. Sandukovsky, S. I. Vasiliev, B. Schwingenheuer, C. Tomei, J. Gasparro, M. Laubenstein, C. A. Ur, M. V. Chirchenko, A. Pullia, Hardy Simgen, V. V. Kuzminov, P. Grabmayr, A. A. Vasenko, and Alessandro Bettini

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, chemistry, Double beta decay, Detector, chemistry.chemical_element, Germanium, Atomic and Molecular Physics, and Optics, Radioactive decay, Semiconductor detector, Diode
Abstract

The Germanium Detector Array (GERDA) in the search for neutrinoless ββ decays of 76Ge at LNGS will operate bare germanium diodes enriched in 76Ge in an (optional active) cryogenic fluid shield to investigate neutrinoless ββ decay with a sensitivity of T 1/2 > 2 × 1026 yr after an exposure of 100 kg yr. Recent progress includes the installation of the first underground infrastructures at Gran Sasso, the completion of the enrichment of 37.5 kg of germanium material for detector construction, prototyping of low-mass detector support and contacts, and front-end and DAQ electronics, as well as the preparation for construction of the cryogenic vessel and water tank.

Published
2006

234. A computer program for the simulation of fiber deposition in the human respiratory tract

Author

Werner Hofmann and Robert Sturm

Subjects
Materials science, Respiratory System, Health Informatics, User-Computer Interface, Computer Graphics, medicine, Humans, Deposition (phase transition), Computer Simulation, Fiber, Particle Size, Mathematical Computing, Simulation, Tidal volume, Mineral Fibers, Lung, Computer program, Respiration, respiratory system, Computer Science Applications, Pulmonary Alveoli, medicine.anatomical_structure, Breathing, Pulmonary Ventilation, Algorithms, Software, Gravitation, Biomedical engineering, Particle deposition, Respiratory tract
Abstract

As inhaled fibers may lead to a variety of lung diseases, detailed information on their deposition in the human respiratory tract is an indispensable requirement in medical science. In the work presented here, a Visual Basic ® computer program, termed FIBROS, is described which enables the simulation of fibrous particle deposition in both the extrathoracic region and different parts of the lung itself, including the results of published numerical studies on inertial/interceptional as well as diffusional and gravitational deposition. The input window of FIBROS includes the selection of specific breathing conditions by variation of the tidal volume and breathing cycle. Furthermore, the user is able to determine fiber properties such as diameter, aspect ratio, specific weight, and fiber orientation with respect to the air stream in the upper and lower airways of the lungs. Besides the offer of various deposition formulae for each region of the respiratory tract, thereby also allowing a distinction between mouth and nose breathing, the user may select between different morphometric datasets of the lung and respective airway scaling procedures. Analysis routines of FIBROS include the estimation of regional deposition fractions, thereby distinguishing between extrathoracic, bronchial, and acinar compartments, and a calculation of generation-by-generation deposition probabilities within tubular and alveolar structures. Preliminary results presented here should demonstrate the effects on fiber deposition due to variations of the breathing behaviour and the particle properties.

Published
2006

235. Prediction of particle deposition in the human lung using realistic models of lung ventilation

Author

B Asgharian, Werner Hofmann, and O T Price

Subjects
Fluid Flow and Transfer Processes, Atmospheric Science, education.field_of_study, Environmental Engineering, Lung, Chemistry, Mechanical Engineering, Airflow, Population, Mechanics, respiratory system, Pollution, respiratory tract diseases, Human lung, medicine.anatomical_structure, Breathing, medicine, Particle, education, Lung ventilation, Particle deposition
Abstract

Realistic predictions of inhaled particle deposition in various locations of the human lung depend mainly on accurate descriptions of the lung geometry and ventilation. Models of airflow distribution in the human lung by uniform and nonuniform lung expansions were used to calculate particle deposition in various lobes and regions of stochastically generated human lungs. To study the influence of lung geometry, 30 asymmetric stochastic lungs were generated and used in the calculations. Lobar airflow in each lung varied in accordance with lobar properties. The calculated airflow distributions indicated that the airflow rate entering each lobe of a given lung was similar for uniform and nonuniform lung expansions. Particle deposition was also found to be similar for uniform and nonuniform lung expansion models at rest breathing. The predicted deposition was in agreement with experimental measurements of regional and total depositions when considering lung size variation in a population. The coupled lung ventilation and deposition models can aid in detailed predictions of inhaled particle deposition in the human lungs.

Published
2006

236. Measurement of the J/ψ production cross section in 920 GeV/c fixed-target proton–nucleus interactions

Author

S. Essenov, M. Adams, Samim Erhan, B. Schwenninger, S. De Castro, P. Kreuzer, Laura Fabbri, C. Padilla, M. Negodaev, D. Goloubkov, D. Ressing, Dmitry Emeliyanov, Yu.T. Kiryushin, E. B. Klinkby, Y. Bagaturia, T. Zivko, Z. Zheng, Mogens Dam, L. Garrido, J. Batista, I. Massa, M. Symalla, L. Matchikhilian, M. Feuerstack-Raible, L. Sozuer, K. M. Danielsen, D. Peralta, Wouter Hulsbergen, I. Vukotic, Maksym Titov, M. Braeuer, S. Shuvalov, M. Ispiryan, Y. Vassiliev, S. Masciocchi, S. Gradl, H. Rick, Pietro Faccioli, V. Aushev, A. J. Schwartz, O. Igonkina, O. Barsukova, V. Rybnikov, M. Schmelling, T. Zeuner, C. B. Krauss, Nicola Semprini-Cesari, I. Belotelov, F. Grimaldi, H. S. Subramania, Brian Petersen, Vladislav Balagura, F. Eisele, S. Korpar, Peter Robmann, U. Schwanke, J. Flammer, M. Starič, S. Somov, M. Ouchrif, Y. Guilitsky, A. Aleksandrov, A. Somov, S. Solunin, I. Abt, Mikhail Danilov, M. T. Nunez Pardo de Vera, M. Agari, Ulrich Werthenbach, H. B. Dreis, Marcus Hohlmann, I. Tsakov, C. Cruse, H. Schroeder, U. Husemann, J. Glaess, R. Zimmermann, R. Maenner, M. Mevius, J. Kessler, Antonio Sbrizzi, A. Wurz, B. Fominykh, R. Mizuk, T. Jagla, M. A. Pleier, M. Poli, X. Dong, N.N. Karpenko, Yu.V. Mikhailov, Farid Ould-Saada, Valery Pugatch, V. Egorytchev, M. Walter, G. Medin, C. Stegmann, P. Krizan, V. Popov, Werner Hofmann, T. Hott, P. Conde, Sebastian Nowak, Igor Golutvin, D. Wegener, António Amorim, A. Vitale, D. Kruecker, H. Wahlberg, W. Gradl, C. Bauer, S. Karabekyan, I. Gorbounov, Yu. Zaitsev, M. Funcke, Jose M Hernandez, A. Bogatyrev, C. Jiang, A. Spiridonov, Antonio Zoccoli, A. S. Schwarz, B. Giacobbe, R. Spighi, S. Prystupa, T. Buran, I. Kisel, M. Bargiotti, Thomas Lohse, Vasco Amaral, A. Michetti, I. Rostovtseva, A. H. Walenta, B. Lewendel, C. van Eldik, M. Noerenberg, J. Bastos, H. Deppe, A. Gellrich, O. Gouchtchine, B. Lomonosov, G. Bohm, R. Muresan, A. Stanovnik, Andrej Gorišek, Hermann Kolanoski, M. Medinnis, D. C. Goulart, Bernhard Schmidt, I. Tikhomirov, S. J. Aplin, Th. S. Bauer, R. Pestotnik, B. Schwingenheuer, Marco Bruschi, H. Albrecht, R. Mankel, R. Wurth, D. Pose, J. Pyrlik, S. Kupper, J.D. Hansen, A. Zhelezov, K. T. Knöpfle, J. Spengler, A. Lanyov, H. Wolters, F. Sciacca, F. Khasanov, S. Keller, Y. Pylypchenko, A. Bertin, Peter Buchholz, Laura Silva, Jian Wang, M. Bruinsma, Kendall Reeves, Maurizio Piccinini, Imma Riu, A. Golutvin, B. Bobchenko, R. Pernack, T. Kvaratskheliia, A. Belkov, K. Ehret, A. Schreiner, M. Boecker, M. zur Nedden, Kwong Lau, F. Sanchez, Mikhail Zavertyaev, U. Uwer, Y. Goloubkov, Mauro Villa, João Carvalho, and H. Kapitza

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Meson, Proton, 010308 nuclear & particles physics, Nuclear Theory, 01 natural sciences, Nuclear physics, Cross section (physics), medicine.anatomical_structure, 0103 physical sciences, medicine, High Energy Physics::Experiment, Production (computer science), Nuclear Experiment, 010306 general physics, Nucleon, Nucleus, Lepton, HERA-B
Abstract

The mid-rapidity ( d σ p N / d y at y = 0 ) and total ( σ p N ) production cross sections of Jψ mesons are measured in proton–nucleus interactions. Data collected by the HERA-B experiment in interactions of 920 GeV / c protons with carbon, titanium and tungsten targets are used for this analysis. The Jψ mesons are reconstructed by their decay into lepton pairs. The total production cross section obtained is σ p N J / ψ = 663 ± 74 ± 46 nb / nucleon . In addition, our result is compared with previous measurements.

Published
2006

237. The LHCb Silicon Tracker Project

Author

H. Voss, J. Blouw, Cristina Lois, S. Löchner, Minh Tâm Tran, Roland Bernet, Werner Hofmann, D. Baumeister, A. Vollhardt, F. Lehner, R. Frei, M. Agari, P. Vasquez, O. Steinkamp, K. T. Knöpfle, U. Straumann, J. Gassner, A. Bay, Valery Pugatch, M. Siegler, Y. Ermoline, C. Bauer, D. Volyanskyy, M. Needham, D. Esperante, R.P. Bernhard, Bernardo Adeva, B. Carron, S. Jiminez-Otero, M. Schmelling, and S. Köstner

Subjects
Nuclear and High Energy Physics, Web of science, Silicon, chemistry, Computer science, business.industry, Embedded system, chemistry.chemical_element, business, Atomic and Molecular Physics, and Optics, Computer hardware
Abstract

Two silicon strip detectors, the Trigger Tracker(TT) and the Inner Tracker(IT) will be constructed for the LHCb experiment. Transverse momentum information extracted from the TT will be used in the Level 1 trigger. The IT is part of the main tracking system behind the magnet. Both silicon detectors will be read out using a custom-developed chip by the ASIC lab in Heidelberg. The signal-over-noise behavior and performance of various geometrical designs of the silicon sensors, in conjunction with the Beetle read-out chip, have been extensively studied in test beam experiments. Results from those experiments are presented, and have been used in the final choice of sensor geometry.

Published
2006

238. Stochastisches Modell zur räumlichen Visualisierung von Teilchendepositionsmustern in der Lunge und ihre Bedeutung in der Lungenmedizin

Author

Robert Sturm and Werner Hofmann

Subjects
Physics, Gynecology, medicine.medical_specialty, Radiological and Ultrasound Technology, Biophysics, medicine, Radiology, Nuclear Medicine and imaging
Abstract

Zusammenfassung Der vorliegende Beitrag widmet sich der ausfuhrlichen Beschreibung einer Erweiterung des auf Basis der Monte-Carlo-Methode funktionierenden Computermodells IDEAL, mit dessen Hilfe die Erzeugung von raumlichen Teilchendepositionsverteilungen in der menschlichen Lunge ermoglicht wird. Nach dem Zufallsprinzip ermittelte Teilchentrajektoren werden durch entsprechende Transformationsprozesse in ein kartesisches Koordinatensystem, in welchem die Richtung der z-Achse durch die Orientierung der Trachea vorgegeben ist, eingepasst, wahrend fur die Bestimmung der Depositionspunkte einzelner Teilchen ein in spezifische Volumenelemente (voxel) unterteiltes Masgitter zur Anwendung gelangt. Die Berechnung der Partikelablagerung basiert dabei auf den physikalischen Mechanismen der Brownschen Diffusion, Sedimentation und Impaktion. Die Depositionsdaten werden nach ihrer Speicherung in einer Matrix einer graphischen Verarbeitung unterzogen, welche die Darstellung raumlicher Partikelverteilungsmuster (3d-Dichteplots) und der Lungenoberflache selbst sowie die Erzeugung zweidimensionaler Verteilungen durch Schnitt der dreidimensionalen Strukturen an vordefinierten Positionen gestattet. Ergebnisse verschiedener Modellsimulationen (Variation der Teilchengrose und Atembedingungen) werden im Detail erlautert.

Published
2006

240. Search for dark matter annihilation signatures in H.E.S.S. observations of dwarf spheroidal galaxies

Author

S. Rosier-Lees, Jacco Vink, Sabrina Casanova, H. Sano, D. Gottschall, P. Vincent, M. J. Vorster, Marie-Hélène Grondin, Christo Venter, V. Sahakian, M. de Naurois, S. J. Fegan, Petter Hofverberg, Denis Wouters, Michael Punch, Stefano Gabici, C. Jahn, Svenja Carrigan, Tanya Edwards, R. Moderski, A. Zech, Quirin Weitzel, G. Fontaine, A. Jacholkowska, J. Lau, A. Ivascenko, I. D. Davids, Y. Cui, E. Birsin, Y. A. Gallant, H.-S. Zechlin, Robert Wagner, Thomas Lohse, W. Kluźniak, J. Becker Tjus, T. Vuillaume, I. Reichardt, H. Laffon, F. Feinstein, Andreas Quirrenbach, F. Krayzel, S. Krakau, G. Heinzelmann, J. Bolmont, Alicja Wierzcholska, Ramin Marx, C. Couturier, D. Fernandez, M. Grudzińska, N. W. Pekeur, Axel Donath, Christian Stegmann, Stefan Wagner, S. Schwarzburg, M. Kieffer, Martin Ward, Cameron B Rulten, P. Wagner, S. Balenderan, P. Willmann, Vincent Marandon, Michal Dyrda, F. Ait Benkhali, M. A. Kastendieck, A. Fiasson, Markus Holler, Andrew M. Taylor, P. P. Krueger, Nachiketa Chakraborty, André Schulz, J. Méhault, Michael Zacharias, S. Schwemmer, Werner Hofmann, Michał Ostrowski, Michael Backes, Emmanuel Moulin, Felix Aharonian, G. Vasileiadis, Dieter Horns, J. Dyks, Anna Barnacka, Ł. Stawarz, O. Hervet, T. Garrigoux, J. Biteau, R. D. Parsons, Jan Conrad, Andrea Santangelo, A. A. Zdziarski, R. C. G. Chaves, K. Valerius, Heinrich J. Völk, Alexandre Marcowith, D. Kolitzus, Pierre Brun, Julien Lefaucheur, Manuel Meyer, Mateusz Janiak, K. Morå, Helen Poon, Gilles Henri, Marek Jamrozy, Pierre-Olivier Petrucci, W. Domainko, A. Wörnlein, M. Panter, A. Balzer, David Berge, Gianluca Giavitto, A. Lopatin, David Sanchez, Guy Pelletier, Ruizhi Yang, L. O'c. Drury, D. Klochkov, A. Djannati-Ataï, A. Förster, S. Häffner, Helene Sol, Stefan Ohm, Uli Katz, S. Pita, J.-P. Lenain, S. Bernhard, Aion Viana, Alison Mitchell, B. van Soelen, B. Rudak, Kathrin Egberts, S. Klepser, B. Degrange, Frank M. Rieger, J. Harris, C. Romoli, Guillaume Dubus, K. Bernloehr, Gavin Rowell, M. Bryan, Matthias Weidinger, David Salek, S. Colafrancesco, Reinhard Schlickeiser, Karl Kosack, Tomasz Bulik, B. Opitz, D. Zaborov, T. Tavernier, R. de los Reyes, Pol Bordas, Yvonne Becherini, F. Stinzing, M. Dalton, B. Giebels, Johan Bregeon, P. M. Chadwick, J.-P. Tavernet, G. Maurin, E. O. Angüner, M. Paz Arribas, M. Mayer, M. Tluczykont, C. Farnier, U. Menzler, K. Dutson, F. Spies, L. Oakes, Ullrich Schwanke, N. Maxted, Francesca Volpe, M. Gajdus, B. Khélifi, Y. Fukui, G. Hermann, Regis Terrier, F. Schüssler, Marianne Lemoine-Goumard, S. J. Nolan, Joachim Hahn, V. Lefranc, Victor Zabalza, A. G. Akhperjanian, R. Chalme-Calvet, Satoshi Yoshiike, Andreas Hillert, R. Steenkamp, K. Stycz, Christoph Deil, S. Raab, A. Abramowski, Catherine Boisson, J. F. Glicenstein, Jim Hinton, Nu. Komin, H. Odaka, M. Füßling, Sarah Kaufmann, J. Veh, Markus Böttcher, T. J. L. McComb, B. Peyaud, R. White, P. J. Meintjes, Francois Brun, M. Chrétien, P. deWilt, K. Katarzyński, P. Espigat, I. Jung-Richardt, I. Oya, Jacek Niemiec, A. Lemière, Olaf Reimer, Thomas Murach, G. Lamanna, Felix Spanier, G. Cologna, C. van Eldik, Felix Jankowsky, M. Renaud, Chia-Chun Lu, G. Pühlhofer, A. Reimer, Iurii Sushch, T. Fukuda, D. Hadasch, G. Spengler, M. Mohamed, M. V. Fernandes, C. Trichard, Peter Eger, H.E.S.S. Collaboration, 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 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 (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Particules de Montpellier (LUPM), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), 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 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), Laboratoire d'Annecy-le-Vieux de Physique Théorique (LAPTH), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), HESS, 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), 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), 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), Université Sciences et Technologies - Bordeaux 1 (UB)-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)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université de Montpellier (UM)-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), 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), and Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules)

Subjects
Nuclear and High Energy Physics, Milky Way, Astrophysics::High Energy Astrophysical Phenomena, Dwarf galaxy problem, Hochenergie-Astrophysik Theorie - Abteilung Hofmann, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Black dwarf, Galaxy group, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, ddc:530, 010303 astronomy & astrophysics, HESS - Abteilung Hofmann, Astrophysics::Galaxy Astrophysics, Dwarf galaxy, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Institut für Physik und Astronomie, Astronomy, Galaxy, Dwarf spheroidal galaxy, Elliptical galaxy, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract

Dwarf spheroidal galaxies of the Local Group are close satellites of the Milky Way characterized by a large mass-to-light ratio and are not expected to be the site of non-thermal high-energy gamma-ray emission or intense star formation. Therefore they are amongst the most promising candidates for indirect dark matter searches. During the last years the High Energy Stereoscopic System (H.E.S.S.) of imaging atmospheric Cherenkov telescopes observed five of these dwarf galaxies for more than 140 hours in total, searching for TeV gamma-ray emission from annihilation of dark matter particles. The new results of the deep exposure of the Sagittarius dwarf spheroidal galaxy, the first observations of the Coma Berenices and Fornax dwarves and the re-analysis of two more dwarf spheroidal galaxies already published by the H.E.S.S. Collaboration, Carina and Sculptor, are presented. In the absence of a significant signal new constraints on the annihilation cross-section applicable to Weakly Interacting Massive Particles (WIMPs) are derived by combining the observations of the five dwarf galaxies. The combined exclusion limit depends on the WIMP mass and the best constraint is reached at 1-2 TeV masses with a cross-section upper bound of ~3.9x10-24 cm^3 s-1 at a 95% confidence level., Comment: to be published in Physical Review D journal; Contact authors: E. Birsin, C. Farnier, G. Lamanna

Published
2014

241. Experimental study of the deposition of combustion aerosols in the human respiratory tract

Author

Werner Hofmann, Cheryl E. Swanson, Jane Hitchins-Loveday, Lidia Morawska, and Kerrie Mengersen

Subjects
Fluid Flow and Transfer Processes, Smoke, Atmospheric Science, Environmental Engineering, Diesel exhaust, Meteorology, Chemistry, Mechanical Engineering, Analytical chemistry, Pollution, Aerosol, Diesel fuel, Deposition (aerosol physics), Scanning mobility particle sizer, Ultrafine particle, Geometric standard deviation
Abstract

The total deposition of environmental tobacco smoke (ETS), diesel and petrol smoke in the respiratory tract of 14 non-smokers between the ages of 20 and 30 was determined experimentally. A scanning mobility particle sizer (SMPS) measuring a size range of 0.016-0.626 mu m was used to characterise the inhaled and exhaled aerosol during relaxed nasal breathing over a period of 10 min. The ETS, diesel, and petrol particles had average count median diameter (and geometric standard deviation) of 0.183 mu m (1.7), 0.125 mu m (1.7), and 0.069 mu m (1.7), respectively. The average total number deposition of ETS was 36% (standard deviation 10%), of diesel smoke 30% (standard deviation 9%), and of petrol smoke 41% (standard deviation 8%). The analysis of the deposition patterns as a function of particle size for the three aerosols in each individual showed that there is a significant difference between each aerosol for a majority of individuals (12 out of 14). This is an important result as it indicates that differences persist regardless of inter-subject variability. (C) 2005 Elsevier Ltd. All rights reserved.

Published
2005

242. Simulation of Three-Dimensional Particle Deposition Patterns in Human Lungs and Comparison with Experimental SPECT Data

Author

John S. Fleming, Joy Conway, Robert Sturm, L. Bolt, and Werner Hofmann

Subjects
Lung deposition, Depot, Chemistry, Shell (structure), Analytical chemistry, Environmental Chemistry, Particle, General Materials Science, Nanotechnology, Pollution, Deposition (chemistry), Particle deposition
Abstract

To further validate a stochastic particle deposition model, three-dimensional deposition patterns predicted by that model were compared with corresponding spatial particle deposition data obtained from SPECT measurements. In the in vivo inhalation experiments, two different polydisperse aerosols with mass median aerodynamic diameters of 1.6 μ m and 6.8 μ m were inhaled by 12 test subjects, using different nebulizers. Predicted and measured deposition data were compared on three different levels: (1) total lung deposition, (2) deposition per hemispherical shell, and (3) deposition per airway generation. First, experimental and theoretical total lung deposition data showed good agreement for both the fine (65 ± 9% vs. 55 ± 21%) and the coarse aerosols (55 ± 8% vs. 46 ± 4%). Second, predicted deposition per hemispherical shell also corresponded well with the experimental data, both exhibiting small deposition fractions in the inner shells and a roughly quadratic increase in the outer shells. Third, fair agre...

Published
2005

243. TeV gamma-ray observations of SS-433 and a survey of the surrounding field with the HEGRA IACT-System

Author

M. Tluczykont, S. Denninghoff, Konrad Bernlöhr, H. Bojahr, N. Götting, I. Jung, G. Pühlhofer, G. Hermann, H. Lampeitl, E. Lorenz, M. Panter, Felix Aharonian, M. Samorski, H. J. Meyer, G. Heinzelmann, M. Girma, M. Beilicke, F. Lucarelli, M. Schilling, Daniel Mazin, R. Mirzoyan, M. Kestel, Dieter Horns, A. Heusler, A. G. Akhperjanian, O. Bolz, A. Kohnle, V. Vitale, R. Kankanyan, W. Wittek, D. Sobzynska, D. Kranich, J. Ripken, M. Siems, Werner Hofmann, M. A. Lopez, O. Mang, Heinrich J. Völk, A. Plyasheshnikov, E. Ona-Wilhelmi, W. Stamm, Jose Luis Contreras, Juan Cortina, H. Börst, C. A. Wiedner, V. Fonseca, Gavin Rowell, R. de los Reyes, Abelardo Moralejo, V. Sahakian, Wolfgang Rhode, A. Konopelko, and T. Coarasa

Subjects
Physics, Space and Planetary Science, Energy transfer, HEGRA, Astronomy and Astrophysics, Champ magnetique, IACT, Astrophysics
Abstract

F. Aharonian, A. Akhperjanian, M. Beilicke, K. Bernlohr, H.-G. Borst, H. Bojahr, O. Bolz, T. Coarasa, J. Contreras, J. Cortina, S. Denninghoff, V. Fonseca, M. Girma, N. Gotting, G. Heinzelmann, G. Hermann, A. Heusler, W. Hofmann, D. Horns, I. Jung, R. Kankanyan, M. Kestel, A. Kohnle, A. Konopelko, D. Kranich, H. Lampeit, M. Lopez, E. Lorenz, F. Lucarelli, O. Mang, D. Mazin, H. Meyer, R. Mirzoyan, A. Moralejo, E. Ona-Wilhelmi, M. Panter, A. Plyasheshnikov, G. Puhlhofer, R. de los Reyes, W. Rhode, J. Ripken, G. P. Rowell, V. Sahakian, M. Samorski, M. Schilling, M. Siems, D. Sobzynska, W. Stamm, M. Tluczykont, V. Vitale, H. J. Volk, C. A. Wiedner, and W. Wittek

Published
2005

244. Simulation of Fiber Deposition in Bronchial Airways

Author

Réka Szöke, Werner Hofmann, Abdel rahman Ahmed, Imre Balásházy, Amer El-Hussein, and M.G. Moustafa

Subjects
Mineral Fibers, Air Pollutants, Inhalation Exposure, Materials science, Lung deposition, business.industry, Health, Toxicology and Mutagenesis, Branching angle, Nanotechnology, Penetration (firestop), Mechanics, Models, Theoretical, Computational fluid dynamics, Toxicology, Volumetric flow rate, Breathing pattern, Inspiratory flow, Humans, business, Lung, Bifurcation
Abstract

Penetration probabilities of inhaled man-made mineral fibers to reach central human airways were computed by a stochastic lung deposition model for different flow rates and equivalent diameters. Results indicate that even thick and long fibers can penetrate into the central airways at low flow rates. Deposition efficiencies and localized deposition patterns were then computed for man-made fibers with variable lengths in a three-dimensional physiologically realistic bifurcation model of the central human airways by computational fluid dynamics (CFD) techniques for characteristic breathing patterns. The results obtained for inspiratory flow conditions indicate that deposition efficiencies were highest for parallel orientation of the fibers, increasing with rising flow rate, branching angle, and fiber length at all orientations. Furthermore, deposition patterns were highly inhomogeneous and their localized distributions showed hot spots in the vicinity of the carinal ridge and at the inner sides of the daughter airways. Comparisons with other theoretical results demonstrate that the equivalent diameter concept, if including interception, presents a reasonable approximation for the parameter ranges employed in the present study.

Published
2005

246. The trigger system of the H.E.S.S. telescope array

Author

F. Toussenel, German Hermann, Konrad Bernlöhr, Werner Hofmann, Stefan Funk, P. Vincent, P. Nayman, David Berge, Jim Hinton, 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), and HESS

Subjects
Photomultiplier, High energy, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, 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, High Energy Stereoscopic System, 010303 astronomy & astrophysics, Cherenkov radiation, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, business.industry, Astrophysics (astro-ph), Emphasis (telecommunications), Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, Level trigger, business, Computer hardware, Energy (signal processing)
Abstract

H.E.S.S. -- The High Energy Stereoscopic System-- is a new system of large atmospheric Cherenkov telescopes for GeV/TeV Gamma-ray astronomy. This paper describes the trigger system of H.E.S.S. with emphasis on the multi-telescope array level trigger. The system trigger requires the simultaneous detection of air-showers by several telescopes at the hardware level. This requirement allows a suppression of background events which in turn leads to a lower system energy threshold for the detection of Gamma-rays. The implementation of the H.E.S.S. trigger system is presented along with data taken to characterise its performance., 20 pages, 12 figures, Accepted for publication in Astroparticle Physics

Published
2004

247. Search for the flavor-changing neutral current decay D0→μ+μ− with the HERA-B detector

Author

A. Alexandrov, Laura Silva, Jian Wang, João Carvalho, H. Kapitza, S. Solunin, Sebastian Nowak, F. Sanchez, S. J. Aplin, B. Schwingenheuer, I. Massa, J. Pyrlik, S. Essenov, Maurizio Piccinini, A. Bertin, D. Wegener, Mikhail Danilov, N.N. Karpenko, L. Matchikhilian, A. Belkov, Mikhail Zavertyaev, Y. Goloubkov, R. Pernack, I. Abt, H. Wahlberg, W. Gradl, C. Cruse, P. Kreuzer, J. Bastos, S. De Castro, K. Smirnov, S. Karabekyan, B. Fominykh, S. Somov, J. Glaess, Yu.V. Mikhailov, R. Spighi, D. Goloubkov, Mauro Villa, M. T. Nunez Pardo de Vera, Dmitry Emeliyanov, T. Zivko, M. Ouchrif, H. B. Dreis, Samo Korpar, A. Wurz, M. Mevius, Ulrich Werthenbach, M. A. Pleier, O. Barsukova, V. Popov, Werner Hofmann, Rok Pestotnik, Robert Harr, R. Muresan, C. Bauer, H. Albrecht, M. zur Nedden, Peter Buchholz, L. Garrido, C. B. Krauss, I. Gorbounov, R. Wurth, D. Pose, A. H. Walenta, Mogens Dam, T. Zeuner, S. Kupper, A. J. Schwartz, D. Kruecker, A. Schreiner, C. Jiang, Kwong Lau, Y. Vassiliev, Y. Guilitsky, I. Belotelov, Wouter Hulsbergen, T. Kvaratskheliia, J. Flammer, A. Stanovnik, I. Tikhomirov, Valery Pugatch, Pietro Faccioli, A. Spiridonov, A. Michetti, M. Funcke, V. Aushev, K. M. Danielsen, H. S. Subramania, S. Nam, B. Schwenninger, Y. Bagaturia, Yu.T. Kiryushin, Y. Pylypchenko, M. Nörenberg, B. Lomonosov, L. Sozuer, J. Kessler, M. Feuerstack-Raible, M. Medinnis, B. Lewendel, Peter Robmann, Antonio Sbrizzi, O. Igonkina, M. Buchler, T. Jagla, X. Dong, Z. Zheng, J. Batista, S. Shuvalov, V. Rybnikov, U. Uwer, Imma Riu, Maksym Titov, C. van Eldik, H. Deppe, M. Bargiotti, A. Golutvin, Thomas Lohse, O. Rick, B. Bobchenko, D. Peralta, J. Shiu, M. Schmelling, I. Vukotic, C. Stegmann, H. Schröder, S. Masciocchi, A. Vitale, Bernhard Schmidt, M. Bruinsma, A. S. Schwarz, P. Krizan, Nicola Semprini-Cesari, M. Symalla, M. Ispiryan, O. Gouchtchine, Th. S. Bauer, Kendall Reeves, G. Bohm, M. Böcker, A. Pose, T. Hott, Laura Fabbri, Marco Bruschi, P. Conde, Igor Golutvin, S. Gradl, C. Padilla, R. Mizuk, Hermann Kolanoski, D. C. Goulart, G. Medin, Farid Ould-Saada, Antonio Zoccoli, Yu. Zaitsev, Vladislav Balagura, Vasco Amaral, I. Tsakov, K. Ehret, F. Eisele, M. Starič, A. Somov, M. Poli, Jose M Hernandez, A. Bogatyrev, D. Ressing, T. Buran, B. Giacobbe, A. Gorisek, S. Prystupa, F. Grimaldi, M. Adams, M. Negodaev, J.D. Hansen, A. Zhelezov, K. T. Knöpfle, V. Egorytchev, M. Bräuer, M. Walter, F. Khasanov, António Amorim, S. Keller, J. Spengler, R. Maenner, A. Lanyov, H. Wolters, F. Sciacca, U. Husemann, and R. Zimmermann

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Particle physics, Neutral current, 010308 nuclear & particles physics, Branching fraction, Flavor-changing neutral current, 0103 physical sciences, Detector, 010306 general physics, 01 natural sciences, HERA-B
Abstract

We report on a search for the flavor-changing neutral current decay D 0 → μ + μ − using 50 × 10 6 events recorded with a dimuon trigger in interactions of 920 GeV protons with nuclei by the HERA-B experiment. We find no evidence for such decays and set a 90% confidence level upper limit on the branching fraction B ( D 0 → μ + μ − ) 2.0 × 10 − 6 .

Published
2004

248. Exploratory cross-sectional investigations on ambient submicrometer particles in Salzburg, Austria

Author

Werner Hofmann, Stephan Thomas, Zoran Ristovski, Lidia Morawska, Thomas Rettenmoser, Milan Jamriska, and Stephan Kagerer

Subjects
Pollutant, Atmospheric Science, Particle number, Meteorology, Air pollution, Atmospheric sciences, medicine.disease_cause, Aerosol, Troposphere, Particle-size distribution, medicine, Particle, Environmental science, Particle size, General Environmental Science
Abstract

Pilot cross-sectional investigations of ambient submicrometer particles were conducted in five locations in the region of Salzburg, Austria. In conclusion, particle size distributions in the urban roadside environment of Salzburg are characterised by three peaks at approximately 0.04, 0.07 and 0.16 μm, the relative height of which varying for different days. Particle concentrations at the sampling sites located in the vicinity of traffic routes are up to 39×10 4 particles cm −3 and are on average an order of magnitude higher than at the suburban location isolated from an immediate impact of traffic. The mountainous non-roadside sites’ particle size distributions are different to those in the urban environment and are characterised by broader peaks shifted towards larger diameters. These sites have particle concentrations lower than Salzburg background. Traffic emissions did not affect airborne concentrations of other monitored pollutants to the same effect as particle number concentrations.

Published
2004

249. Observation of the Monoceros Loop SNR region with the HEGRA system of IACTs

Author

H. J. Meyer, M. V. Fonseca, M. Tluczykont, S. Denninghoff, R. Mirzoyan, M. Samorski, H. Lampeitl, E. Lorenz, A. G. Akhperjanian, W. Stamm, M. Beilicke, J. Ripken, M. A. Lopez, M. Panter, A. Kohnle, Konrad Bernlöhr, Dieter Horns, H. Kornmeyer, H. Bojahr, Felix Aharonian, M. Girma, G. Hermann, D. Sobzynska, R. Kankanyan, I. Jung, M. Schilling, Heinrich J. Völk, Werner Hofmann, F. Lucarelli, M. Kestel, N. Götting, Gavin Rowell, A. Heusler, R. de los Reyes, O. Mang, V. Sahakian, A. Plyasheshnikov, A. Konopelko, Jose Luis Contreras, Juan Cortina, H. Börst, C. A. Wiedner, G. Heinzelmann, M. Siems, W. Wittek, O. Bolz, V. Vitale, Wolfgang Rhode, D. Kranich, Abelardo Moralejo, E. Ona-Wilhelmi, Gerd Pühlhofer, and T. Coarasa

Subjects
Physics, Nebula, Point source, Astrophysics::High Energy Astrophysical Phenomena, media_common.quotation_subject, Molecular cloud, Astrophysics::Instrumentation and Methods for Astrophysics, Gamma ray, HEGRA, Astronomy, Astronomy and Astrophysics, Field of view, Astrophysics, Gamma-ray astronomy, Space and Planetary Science, Sky, Astrophysics::Galaxy Astrophysics, media_common
Abstract

The array of 5 imaging atmospheric y Cerenkov telescopes (IACTs) deployed at La Palma (Canary Islands), and operated by the HEGRA (High Energy Gamma Ray Astronomy) collaboration, was used for observations of the Monoceros Loop SNR region for a total of about 120 hrs and 20 hrs in ON-source and OFF-source mode, respectively. The giant molecular cloud Rosette Nebula appears in the sky region, close to the south-east part of the SNR rim. Using the HEGRA system of IACTs of rather large field of view (4.3 degree in diameter), we have mapped the extended sky region of 3 ◦ × 3 ◦ associated with the Monoceros SNR/Rosette Nebula, which is centered towards the hard spectrum X-ray point source SAX J0635+533. The EGRET unidentified source of diffuse γ-ray emission (3EG J0634+0521) observed in the energy range between 100 MeV-10 GeV, was effectively in the field of view of our present observations. Also, the GeV source GeV J0633+0645 was within the available field of view. The performance of the IACTs array reveals an energy threshold of 500 GeV and an angular resolution of 0.1 ◦ for γ-rays. In what follows, we present the result of the data analysis and its physical interpretation.

Published
2004

250. Appendix B Analysis of Results of the Nuclear Track Detector Exposure at PTB in View of Cross Sensitivity to Radon/Thoron and the Determination of Decision Threshold and Detection Limit

Author

J. McLaughlin, H.S. Arvela, Naomi H. Harley, J.W. Marsh, S. Tokonami, Werner Hofmann, and A. Röttger

Subjects
Physics, Nuclear physics, Detection limit, Radiation, Nuclear track, chemistry, Cross sensitivity, Detector, Biophysics, chemistry.chemical_element, Radon, Radiology, Nuclear Medicine and imaging, Decision threshold
Published
2012

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