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151. Discovery of VHE emission towards the Carina arm region with the H.E.S.S. telescope array: HESS J1018-589

Author: HESS Collaboration, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Balzer, A., Barnacka, A., de Almeida, U. Barres, Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Birsin, E., Biteau, J., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Clapson, A. C., Coignet, G., Cologna, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubus, G., Dutson, K., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Förster, A., Füßling, M., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Häffner, S., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holler, M., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzyński, K., Katz, U., Kaufmann, S., Keogh, D., Khangulyan, D., Khélifi, B., Klochkov, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., Mayer, M., McComb, T. J. L., Medina, M. C., Méhault, J., Moderski, R., Moulin, E., Naumann, C. L., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Wilhelmi, E. de Oña, Opitz, B., Ostrowski, M., Oya, I., Panter, M., Arribas, M. Paz, Pedaletti1, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Sahakian, V., Sanchez, D. A., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Sheidaei, F., Skilton, J. L., Sol, H., Spengler, G., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Stycz, K., Sushch, I., Szostek, A., Tavernet, J. -P., Terrier, R., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., White, R., Wierzcholska, A., Zacharias, M., Zajczyk, A., Zdziarski, A. A., Zech, A., and Zechlin, H. -S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The observational coverage with HESS of the Carina region in VHE gamma-rays benefits from deep exposure (40 h) of the neighboring open cluster Westerlund 2. The observations have revealed a new extended region of VHE gamma-ray emission. The new VHE source HESS J1018-589 shows a bright, point-like emission region positionally coincident with SNR G284.3-1.8 and 1FGL J1018.6 - 5856 and a diffuse extension towards the direction of PSR J1016-5857. A soft Gamma=2.7+-0.5 photon index, with a differential flux at 1TeV of N0=(4.2+-1.1)10^-13 TeV^-1 cm^-2 s^-1 is found for the point-like source, whereas the total emission region including the diffuse emission region is well fit by a power-law function with spectral index Gamma=2.9+-0.4 and differential flux at 1TeV of N0=(6.8+-1.6) 10^-13 TeV^-1 cm^-2 s^-1. This H.E.S.S. detection motivated follow-up X-ray observations with the XMM-Newton satellite to investigate the origin of the VHE emission. The analysis of the XMM-Newton data resulted in the discovery of a bright, non-thermal point-like source (XMMU J101855.4-58564) with a photon index of Gamma=1.65+-0.08 in the center of SNRG284.3-1.8, and a thermal, extended emission region coincident with its bright northern filament. The characteristics of this thermal emission are used to estimate the plasma density in the region as n~0.5 cm^-3(2.9kpc/d)^2. The position of XMMUJ101855.4-58564 is compatible with the position reported by the Fermi-LAT collaboration for the binary system 1FGL J1018.6-5856 and the variable Swift XRT source identified with it. The new X-ray data are used alongside archival multi-wavelength data to investigate the relationship between the VHE gamma-ray emission from HESSJ1018-589 and the various potential counterparts in the Carina arm region., Comment: accepted in A&A
Published: 2012
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152. Search for Dark Matter Annihilation Signals from the Fornax Galaxy Cluster with H.E.S.S

Author: HESS Collaboration, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Balzer, A., Barnacka, A., de Almeida, U. Barres, Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Birsin, E., Biteau, J., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Clapson, A. C., Coignet, G., Cologna, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubus, G., Dutson, K., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Förster, A., Füßling, M., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Häffner, S., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holler, M., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzyński, K., Katz, U., Kaufmann, S., Keogh, D., Khangulyan, D., Khélifi, B., Klochkov, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., Mayer, M., McComb, T. J. L., Medina, M. C., Méhault, J., Moderski, R., Moulin, E., Naumann, C. L., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Wilhelmi, E. de Oña, Opitz, B., Ostrowski, M., Oya, I., Panter, M., Arribas, M. Paz, Pedaletti1, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Sahakian, V., Sanchez, D. A., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Sheidaei, F., Skilton, J. L., Sol, H., Spengler, G., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Stycz, K., Sushch, I., Szostek, A., Tavernet, J. -P., Terrier, R., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., White, R., Wierzcholska, A., Zacharias, M., Zajczyk, A., Zdziarski, A. A., Zech, A., and Zechlin, H. -S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The Fornax galaxy cluster was observed with the High Energy Stereoscopic System (H.E.S.S.) for a total live time of 14.5 hours, searching for very-high-energy (VHE, E>100 GeV) gamma-rays from dark matter (DM) annihilation. No significant signal was found in searches for point-like and extended emissions. Using several models of the DM density distribution, upper limits on the DM velocity-weighted annihilation cross-section as a function of the DM particle mass are derived. Constraints are derived for different DM particle models, such as those arising from Kaluza-Klein and supersymmetric models. Various annihilation final states are considered. Possible enhancements of the DM annihilation gamma-ray flux, due to DM substructures of the DM host halo, or from the Sommerfeld effect, are studied. Additional gamma-ray contributions from internal bremsstrahlung and inverse Compton radiation are also discussed. For a DM particle mass of 1 TeV, the exclusion limits at 95% of confidence level reach values of ~ 10^-23cm^3s^-1, depending on the DM particle model and halo properties. Additional contribution from DM substructures can improve the upper limits on <\sigma v> by more than two orders of magnitude. At masses around 4.5 TeV, the enhancement by substructures and the Sommerfeld resonance effect results in a velocity-weighted annihilation cross-section upper limit at the level of <\sigma v> ~ 10^-26cm^3s^-1., Comment: 16 pages, 9 figures, 4 tables, accepted for publication in ApJ, Figures 5 and 7 corrected to match erratum
Published: 2012
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153. A multiwavelength view of the flaring state of PKS 2155-304 in 2006

Author: HESS Collaboration, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Balzer, A., Barnacka, A., de Almeida, U. Barres, Becherini, Y., Becker, J., Behera, B., Benbow, W., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Boutelier, T., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Cologna, G., Colom, P., Conrad, J., Coudreau, N., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dutson, K., Dyks, J., Dyrda, M., Edwards, P., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Förster, A., Füßling, M., Gallant, Y. A., Gast, H., Gaylard, M. J., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Häffner, S., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holler, M., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzyński, K., Katz, U., Kaufmann, S., Keogh, D., Khangulyan, D., Khélifi, B., Klein, M., Klochkov, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Kubanek, P., Laffon, H., Lamanna, G., Lennarz, D., Lenain, J. -P., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Martin, J. M., Masbou, J., Maurin, D., Maxted, N., McComb, T. J. L., Medina, M. C., Méhault, J., Melady, G., Nguyen, N., Moderski, R., Monard, B., Moulin, E., Naumann, C. L., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Wilhelmi, E. de Oña, Opitz, B., Ostrowski, M., Oya, I., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Sikora, M., Skilton, J. L., Sol, H., Spengler, G., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Stycz, K., Sushch, I., Szostek, A., Tavernet, J. -P., Terrier, R., Tluczykont, M., Tzioumis, A., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Venter, L., Vialle, J. P., Viana, A., Vincent, P., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., White, R., Wierzcholska, A., Zacharias, M., Zajczyk, A., Zdziarski, A. A., Zech, A., and Zechlin, H. -S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Multiwavelength (MWL) observations of the blazar PKS 2155-304 during two weeks in July and August 2006, the period when two exceptional flares at very high energies (VHE, E>= 100 GeV) occurred, provide a detailed picture of the evolution of its emission. The complete data set from this campaign is presented, including observations in VHE gamma-rays (H.E.S.S.), X-rays (RXTE, CHANDRA, SWIFT XRT), optical (SWIFT UVOT, Bronberg, Watcher, ROTSE), and in the radio band (NRT, HartRAO, ATCA). Optical and radio light curves from 2004 to 2008 are compared to the available VHE data from this period, to put the 2006 campaign into the context of the long-term evolution of the source. The X-ray and VHE gamma-ray emission are correlated during the observed high state of the source, but show no direct connection with longer wavelengths. The long-term flux evolution in the optical and radio bands is found to be correlated and shows that the source reaches a high state at long wavelengths after the occurrence of the VHE flares. Spectral hardening is seen in the SWIFT XRT data. The nightly averaged high-energy spectra of the non-flaring nights can be reproduced by a stationary one-zone SSC model, with only small variations in the parameters. The spectral and flux evolution in the high-energy band during the night of the second VHE flare is modelled with multi-zone SSC models, which can provide relatively simple interpretations for the hour time-scale evolution of the high-energy emission, even for such a complex data set. For the first time in this type of source, a clear indication is found for a relation between high activity at high energies and a long-term increase in the low frequency fluxes., Comment: 23 pages, 13 figures, accepted for publication in Astronomy & Astrophysics
Published: 2012
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154. Discovery of hard-spectrum \gamma-ray emission from the BL Lac object 1ES 0414+009

Author: The HESS Collaboration, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Balzer, A., Barnacka, A., de Almeida, U. Barres, Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Birsin, E., Biteau, J., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Cologna, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dutson, K., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Förster, A., Füßling, M., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Häffner, S., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holler, M., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzynski, K., Katz, U., Kaufmann, S., Keogh, D., Khangulyan, D., Khélifi, B., Kluźniak, D. Klochkov W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., Mayer, M., McComb, T. J. L., Medina, M. C., Méhault, J., Moderski, R., Moulin, E., Naumann, C. L., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Wilhelmi, E. de Ona, Opitz, B., Ostrowski, M., Oya, I., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Sahakian, V., Sanchez, D. A., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Sheidaei, F., Sikora, M., Skilton, J. L., Sol, H., Spengler, G., Stawarz, L., Steenkamp, R., Stegmann, C., Stinzing, F., Stycz, K., Sushch, I., Szostek, A., Tavernet, J. -P., Terrier, R., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., White, R., Wierzcholska, A., Zacharias, M., Zajczyk, A., Zdziarski, A. A., Zech, A., Zechlin, H. -S., Costamante, L., Fegan, S., and Ajello, M.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: 1ES 0414+009 (z = 0.287) is a distant high-frequency-peaked BL Lac object, and has long been considered a likely emitter of very-high energy (VHE, E>100 GeV) gamma-rays due to its high X-ray and radio flux. Observations in the VHE gamma-ray band and across the electromagnetic spectrum can provide insights into the origin of highly energetic particles present in the source and the radiation processes at work. Because of the distance of the source, the gamma-ray spectrum might provide further limits on the level of the Extragalactic Background Light (EBL). We report observations made between October 2005 and December 2009 with H.E.S.S., an array of four imaging atmospheric Cherenkov telescopes. Observations at high energies (HE, 100 MeV - 100 GeV) with the Fermi-LAT instrument in the first 20 months of its operation are also reported. To complete the multi-wavelength picture, archival UV and X-ray observations with the Swift satellite and optical observations with the ATOM telescope are also used. Based on the observations with H.E.S.S., 1ES 0414+009 is detected for the first time in the VHE band. An excess of 224 events is measured, corresponding to a significance of 7.8 sigma. The photon spectrum of the source is well described by a power law, with photon index of 3.45 \pm 0.25stat \pm 0.20syst. The integral flux above 200 GeV is (1.88 \pm 0.20stat \pm 0.38syst) \times10-12 cm-2 s-1. Observations with the Fermi-LAT in the first 20 months of operation show a flux between 200 MeV and 100 GeV of (2.3 \pm 0.2stat) \times 10-9 erg cm-2 s-1, and a spectrum well described by a power-law function with a photon index 1.85 \pm 0.18. Swift/XRT observations show an X-ray flux between 2 and 10 keV of (0.8 - 1) \times 10-11 erg cm-2 s-1, and a steep spectrum (2.2 - 2.3). Combining X-ray with optical-UV data, a fit with a log-parabolic function locates the synchrotron peak around 0.1 keV. ..., Comment: 9 pages, 4 figures, accepted for publication in A&A
Published: 2012
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155. Discovery of VHE gamma-ray emission from the SNR G15.4+0.1 with H.E.S.S

Author: Hofverberg, P., Chaves, R. C. G., Méhault, J., and de Naurois, M.
Subjects: Astrophysics - Astrophysics of Galaxies
Abstract: Supernova remnants (SNRs) have emerged as one of the largest source classes in very-high-energy (VHE; E>0.1,TeV) astronomy. Many of the now known VHE gamma-ray emitting SNRs have been discovered by the H.E.S.S. imaging Cherenkov telescope array, thanks to its unique access to the inner galaxy. Statistically-significant emission of VHE gamma rays has now been detected from the direction of the supernova remnant G15.4+0.1. While the centroids of the H.E.S.S. source and the shell-type SNR are compatible, the VHE morphology suggests a center-dominated source at TeV energies, something which is at odds with the shell-like morphology observed at radio frequencies. This suggests that H.E.S.S. may be observing TeV emission from a previously unknown pulsar wind nebula (PWN) located within the boundaries of the radio shell. If this interpretation is correct, G15.4+0.1 would in fact be a composite SNR, the first case in which an SNR is identified as a composite on the basis of VHE gamma-ray observations. Archival data from MAGPIS gives exciting hints that there is radio emission from the central parts of the remnant, giving support to this hypothesis. Unfortunately, image artefacts from a nearby strong radio source produce considerable uncertainties in the radio analysis. Additional observations in both the radio and X-ray are needed to confirm the composite nature of G15.4+0.1 suggested by H.E.S.S.
Published: 2011
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156. The 2010 very high energy gamma-ray flare & 10 years of multi-wavelength observations of M 87

Author: Collaboration, The H. E. S. S., Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Balzer, A., Barnacka, A., de Almeida, U. Barres, Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Birsin, E., Biteau, J., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Clapson, A. C., Coignet, G., Cologna, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubus, G., Dutson, K., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Förster, A., Füßling, M., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Häffner, S., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holler, M., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzyński, K., Katz, U., Kaufmann, S., Keogh, D., Khangulyan, D., Khélifi, B., Klochkov, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., Mayer, M., McComb, T. J. L., Medina, M. C., Méhault, J., Moderski, R., Moulin, E., Naumann, C. L., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Wilhelmi, E. de Oña, Opitz, B., Ostrowski, M., Oya, I., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Sahakian, V., Sanchez, D. A., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Sheidaei, F., Skilton, J. L., Sol, H., Spengler, G., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Stycz, K., Sushch, I., Szostek, A., Tavernet, J. -P., Terrier, R., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., White, R., Wierzcholska, A., Zacharias, M., Zajczyk, A., Zdziarski, A. A., Zech, A., Zechlin, H. -S., Collaboration, The MAGIC, Aleksić, J., Antonelli, L. A., Antoranz, P., Backes, M., Barrio, J. A., Bastieri, D., González, J. Becerra, Bednarek, W., Berdyugin, A., Berger, K., Bernardini, E., Biland, A., Blanch, O., Bock, R. K., Boller, A., Bonnoli, G., Tridon, D. Borla, Braun, I., Bretz, T., Cañellas, A., Carmona, E., Carosi, A., Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Cossio, L., Covino, S., Dazzi, F., De Angelis, A., del Pozo, E. De Cea, De Lotto, B., Mendez, C. Delgado, Ortega, A. Diago, Doert, M., Domínguez, A., Prester, D. Dominis, Dorner, D., Doro, M., Elsaesser, D., Ferenc, D., Fonseca, M. V., Font, L., Fruck, C., López, R. J. García, Garczarczyk, M., Garrido, D., Giavitto, G., Godinović, N., Hadasch, D., Häfner, D., Herrero, A., Hildebrand, D., Höhne-Mönch, D., Hose, J., Hrupec, D., Huber, B., Jogler, T., Klepser, S., Krähenbühl, T., Krause, J., La Barbera, A., Lelas, D., Leonardo, E., Lindfors, E., Lombardi, S., López, M., Lorenz, E., Makariev, M., Maneva, G., Mankuzhiyil, N., Mannheim, K., Maraschi, L., Mariotti, M., Martínez, M., Mazin, D., Meucci, M., Miranda, J. M., Mirzoyan, R., Miyamoto, H., Moldón, J., Moralejo, A., Munar, P., Nieto, D., Nilsson, K., Orito, R., Paneque, D., Paoletti, R., Pardo, S., Paredes, J. M., Partini, S., Pasanen, M., Pauss, F., Perez-Torres, M. A., Persic, M., Peruzzo, L., Pilia, M., Pochon, J., Prada, F., Moroni, P. G. Prada, Prandini, E., Puljak, I., Reichardt, I., Reinthal, R., Rhode, W., Ribó, M., Rico, J., Rügamer, S., Saggion, A., Saito, K., Saito, T. Y., Salvati, M., Satalecka, K., Scalzotto, V., Scapin, V., Schultz, C., Schweizer, T., Shayduk, M., Shore, S. N., Sillanpää, A., Sitarek, J., Sobczynska, D., Spanier, F., Spiro, S., Stamerra, A., Steinke, B., Storz, J., Strah, N., Surić, T., Takalo, L., Takami, H., Tavecchio, F., Temnikov, P., Terzić, T., Tescaro, D., Teshima, M., Thom, M., Tibolla, O., Torres, D. F., Treves, A., Vankov, H., Vogler, P., Wagner, R. M., Weitzel, Q., Zabalza, V., Zandanel, F., Zanin, R., Collaboration, The VERITAS, Arlen, T., Aune, T., Beilicke, M., Benbow, W., Bouvier, A., Bradbury, S. M., Buckley, J. H., Bugaev, V., Byrum, K., Cannon, A., Cesarini, A., Ciupik, L., Connolly, M. P., Cui, W., Dickherber, R., Duke, C., Errando, M., Falcone, A., Finley, J. P., Finnegan, G., Fortson, L., Furniss, A., Galante, N., Gall, D., Godambe, S., Griffin, S., Grube, J., Gyuk, G., Hanna, D., Holder, J., Huan, H., Hui, C. M., Kaaret, P., Karlsson, N., Kertzman, M., Khassen, Y., Kieda, D., Krawczynski, H., Krennrich, F., Lang, M. J., LeBohec, S., Maier, G., McArthur, S., McCann, A., Moriarty, P., Mukherjee, R., Nuñez, P. D., Ong, R. A., Orr, M., Otte, A. N., Park, N., Perkins, J. S., Pichel, A., Pohl, M., Prokoph, H., Ragan, K., Reyes, L. C., Reynolds, P. T., Roache, E., Rose, H. J., Schroedter, M., Sembroski, G. H., Şentürk, G. D., Telezhinsky, I., Tešić, G., Theiling, M., Thibadeau, S., Varlotta, A., Vassiliev, V. V., Vivier, M., Wakely, S. P., Weekes, T. C., Williams, D. A., Zitzer, B., Cara, M., Casadio, C., Cheung, C. C., McConville, W., Davies, F., Doi, A., Giovannini, G., Giroletti, M., Hada, K., Hardee, P., Harris, D. E., Junor, W., Kino, M., Lee, N. P., Ly, C., Madrid, J., Massaro, F., Mundell, C. G., Nagai, H., Perlman, E. S., Steele, I. A., Walker, R. C., and Wood, D. L.
Subjects: Astrophysics - Cosmology and Extragalactic Astrophysics
Abstract: Abridged: The giant radio galaxy M 87 with its proximity, famous jet, and very massive black hole provides a unique opportunity to investigate the origin of very high energy (VHE; E>100 GeV) gamma-ray emission generated in relativistic outflows and the surroundings of super-massive black holes. M 87 has been established as a VHE gamma-ray emitter since 2006. The VHE gamma-ray emission displays strong variability on timescales as short as a day. In this paper, results from a joint VHE monitoring campaign on M 87 by the MAGIC and VERITAS instruments in 2010 are reported. During the campaign, a flare at VHE was detected triggering further observations at VHE (H.E.S.S.), X-rays (Chandra), and radio (43 GHz VLBA). The excellent sampling of the VHE gamma-ray light curve enables one to derive a precise temporal characterization of the flare: the single, isolated flare is well described by a two-sided exponential function with significantly different flux rise and decay times. While the overall variability pattern of the 2010 flare appears somewhat different from that of previous VHE flares in 2005 and 2008, they share very similar timescales (~day), peak fluxes (Phi(>0.35 TeV) ~= (1-3) x 10^-11 ph cm^-2 s^-1), and VHE spectra. 43 GHz VLBA radio observations of the inner jet regions indicate no enhanced flux in 2010 in contrast to observations in 2008, where an increase of the radio flux of the innermost core regions coincided with a VHE flare. On the other hand, Chandra X-ray observations taken ~3 days after the peak of the VHE gamma-ray emission reveal an enhanced flux from the core. The long-term (2001-2010) multi-wavelength light curve of M 87, spanning from radio to VHE and including data from HST, LT, VLA and EVN, is used to further investigate the origin of the VHE gamma-ray emission. No unique, common MWL signature of the three VHE flares has been identified., Comment: 19 pages, 5 figures; Corresponding authors: M. Raue, L. Stawarz, D. Mazin, P. Colin, C. M. Hui, M. Beilicke; Fig. 1 lightcurve data available online: http://www.desy.de/~mraue/m87/
Published: 2011
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157. Simultaneous multi-wavelength campaign on PKS 2005-489 in a high state

Author: Collaboration, The H. E. S. S., Collaboration, the Fermi LAT, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Barnacka, A., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Borrel, V., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Förster, A., Füßling, M., Gabici, S., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzyński, K., Katz, U., Kaufmann, S., Keogh, D., Kerschhaggl, M., Khangulyan, D., Khélifi, B., Klochkov, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lenain, J. -P., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., McComb, T. J. L., Medina, M. C., Méhault, J., Nguyen, N., Moderski, R., Moulin, E., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-F., Wilhelmi, E. de Oña, Opitz, B., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schönwald, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Shalchi, A., Sikora, M., Skilton, J. L., Sol, H., Spengler, G., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Sushch, I., Szostek, A., Tam, P. H., Tavernet, J. -P., Terrier, R., Tibolla, O., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Vivier, M., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., Wierzcholska, A., Zajczyk, A., Zdziarski, A. A., Zech, A., Zechlin, H. -S., Abdo, A. A., Ackermann, M., Ajello, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bonamente, E., Borgland, A. W., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Cannon, A., Caraveo, P. A., Carrigan, S., Casandjian, J. M., Cavazzuti, E., Cecchi, C., Çelik, Ö., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Cutini, S., Dermer, C. D., de Palma, F., Silva, E. do Couto e, Drell, P. S., Dubois, R., Dumora, D., Escande, L., Favuzzi, C., Ferrara, E. C., Focke, W. B., Fortin, P., Frailis, M., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guiriec, S., Hadasch, D., Hays, E., Horan, D., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Knödlseder, J., Kuss, M., Lande, J., Latronico, L., Lee, S. -H., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Makeev, A., Mazziotta, M. N., McConville, W., McEnery, J. E., Michelson, P. F., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Nishino, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ormes, J. F., Ozaki, M., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piron, F., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Sadrozinski, H. F. -W., Sanchez, D., Sander, A., Sgrò, C., Siskind, E. J., Smith, P. D., Spandre, G., Spinelli, P., Strickman, M. S., Suson, D. J., Takahashi, H., Takahashi, T., Tanaka, T., Thayer, J. B., Thayer, J. G., Thompson, D. J., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Troja, E., Uehara, T., Usher, T. L., Vandenbroucke, J., Vianello, G., Vilchez, N., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., Yang, Z., Ylinen, T., and Ziegler, M.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The high-frequency peaked BL Lac object PKS 2005-489 was the target of a multi-wavelength campaign with simultaneous observations in the TeV gamma-ray (H.E.S.S.), GeV gamma-ray (Fermi/LAT), X-ray (RXTE, Swift), UV (Swift) and optical (ATOM, Swift) bands. This campaign was carried out during a high flux state in the synchrotron regime. The flux in the optical and X-ray bands reached the level of the historical maxima. The hard GeV spectrum observed with Fermi/LAT connects well to the very high energy (VHE, E>100GeV) spectrum measured with H.E.S.S. with a peak energy between ~5 and 500 GeV. Compared to observations with contemporaneous coverage in the VHE and X-ray bands in 2004, the X-ray flux was ~50 times higher during the 2009 campaign while the TeV gamma-ray flux shows marginal variation over the years. The spectral energy distribution during this multi-wavelength campaign was fit by a one zone synchrotron self-Compton model with a well determined cutoff in X-rays. The parameters of a one zone SSC model are inconsistent with variability time scales. The variability behaviour over years with the large changes in synchrotron emission and small changes in the inverse Compton emission does not warrant an interpretation within a one-zone SSC model despite an apparently satisfying fit to the broadband data in 2009., Comment: published in A&A, 9pages, 4figures. Due to some style difficulties using the standard style file with the long author list, the abstract has been included manually. A version with the correct style can be found in the website http://www.lsw.uni-heidelberg.de/users/skaufman/publications/aa16170-10published.pdf
Published: 2011
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158. Discovery of extended VHE \gamma-ray emission from the vicinity of the young massive stellar cluster Westerlund 1

Author: HESS Collaboration, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Balzer, A., Barnacka, A., de Almeida, U. Barres, Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Birsin, E., Biteau, J., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Cologna, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dutson, K., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Förster, A., Füßling, M., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Häffner, S., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holler, M., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzynski, K., Katz, U., Kaufmann, S., Keogh, D., Khangulyan, D., Khélifi, B., Klochkov, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., Mayer, M., McComb, T. J. L., Medina, M. C., Méhault, J., Moderski, R., Moulin, E., Naumann, C. L., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Wilhelmi, E. de Ona, Opitz, B., Ostrowski, M., Oya, I., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Sahakian, V., Sanchez, D., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Sheidaei, F., Sikora, M., Skilton, J. L., Sol, H., Spengler, G., Stawarz, L., Steenkamp, R., Stegmann, C., Stinzing, F., Stycz, K., Sushch, I., Szostek, A., Tavernet, J. -P., Terrier, R., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., White, R., Wierzcholska, A., Zacharias, M., Zajczyk, A., Zdziarski, A. A., Zech, A., and Zechlin, H. -S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Galaxy Astrophysics
Abstract: Results obtained in very-high-energy (VHE; E > 100 GeV) \gamma-ray observations performed with the H.E.S.S. telescope array are used to investigate particle acceleration processes in the vicinity of the young massive stellar cluster Westerlund 1 (Wd 1). Imaging of Cherenkov light from \gamma-ray induced particle cascades in the Earth's atmosphere is used to search for VHE \gamma\ rays from the region around Wd 1. Possible catalogued counterparts are searched for and discussed in terms of morphology and energetics of the H.E.S.S. source. The detection of the degree-scale extended VHE \gamma-ray source HESS J1646-458 is reported based on 45 hours of H.E.S.S. observations performed between 2004 and 2008. The VHE \gamma-ray source is centred on the nominal position of Wd 1 and detected with a total statistical significance of ~20\sigma. The emission region clearly extends beyond the H.E.S.S. point-spread function (PSF). The differential energy spectrum follows a power law in energy with an index of \Gamma=2.19 \pm 0.08_{stat} \pm 0.20_{sys} and a flux normalisation at 1 TeV of \Phi_0 = (9.0 \pm 1.4_{stat} \pm 1.8_{sys}) x 10^{-12} TeV^{-1} cm^{-2} s^{-1}. The integral flux above 0.2 TeV amounts to (5.2 \pm 0.9) x 10^{-11} cm^{-2} s^{-1}. Four objects coincident with HESS J1646-458 are discussed in the search of a counterpart, namely the magnetar CXOU J164710.2-455216, the X-ray binary 4U 1642-45, the pulsar PSR J1648-4611 and the massive stellar cluster Wd 1. In a single-source scenario, Wd 1 is favoured as site of VHE particle acceleration. Here, a hadronic parent population would be accelerated within the stellar cluster. Beside this, there is evidence for a multi-source origin, where a scenario involving PSR J1648-4611 could be viable to explain parts of the VHE \gamma-ray emission of HESS J1646-458., Comment: 11 pages, 6 figures, accepted for publication in A&A
Published: 2011
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159. Discovery of the source HESS J1356-645 associated with the young and energetic PSR J1357-6429

Author: HESS Collaboration, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Balzer, A., Barnacka, A., de Almeida, U. Barres, Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Cologna, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dutson, K., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Förster, A., Füssling, M., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Häffner, S., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holler, M., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzynski, K., Katz, U., Kaufmann, S., Keogh, D., Khangulyan, D., Khélifi, B., Klochkov, D., Kluzniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., Mayer, M., McComb, T. J. L., Medina, M. C., Méhault, J., Moderski, R., Moulin, E., Naumann, C. L., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Wilhelmi, E. de Ona, Opitz, B., Ostrowski, M., Oya, I., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Sahakian, V., Sanchez, D., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Sikora, M., Skilton, J. L., Sol, H., Spengler, G., Stawarz, L., Steenkamp, R., Stegmann, C., Stinzing, F., Stycz, K., Sushch, I., Szostek, A., Tavernet, J. -P., Terrier, R., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., White, R., Wierzcholska, A., Zacharias, M., Zajczyk, A., Zdziarski, A. A., Zech, A., and Zechlin, H. -S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Several newly discovered very-high-energy (VHE; E > 100 GeV) gamma-ray sources in the Galaxy are thought to be associated with energetic pulsars. Among them, middle-aged (> 1E+4 yr) systems exhibit large centre-filled VHE nebulae, offset from the pulsar position, which result from the complex relationship between the pulsar wind and the surrounding medium, and reflect the past evolution of the pulsar. Imaging Atmospheric Cherenkov Telescopes (IACTs) have been successful in revealing extended emission from these sources in the VHE regime. Together with radio and X-ray observations, this observational window allows one to probe the energetics and magnetic field inside these large-scale nebulae. H.E.S.S., with its large field of view, angular resolution of < 0.1deg and unprecedented sensitivity, has been used to discover a large population of such VHE sources. In this paper, the H.E.S.S. data from the continuation of the Galactic Plane Survey (-80deg < l < 60deg, |b| < 3deg), together with the existing multi-wavelength observations, are used. A new VHE gamma-ray source was discovered at R.A. (J2000) = 13h56m00s, Dec. (J2000) = -64d30m00s with a 2' statistical error in each coordinate, namely HESS J1356-645. The source is extended, with an intrinsic Gaussian width of (0.20 +/- 0.02)deg. Its integrated energy flux between 1 and 10 TeV of 8E-12 erg cm-2 s-1 represents ~ 11% of the Crab Nebula flux in the same energy band. The energy spectrum between 1 and 20 TeV is well described by a power law dN/dE ~ E-Gamma with photon index Gamma = 2.2 +/- 0.2stat +/- 0.2sys. The inspection of archival radio images at three frequencies and the analysis of X-ray data from ROSAT/PSPC and XMM-Newton/MOS reveal the presence of faint non-thermal diffuse emission coincident with HESS J1356-645. HESS J1356-645 is most likely associated with the young and energetic pulsar PSR J1357-6429 (Abridged), Comment: Accepted for publication in A&A (August 08th 2011); 11 pages, 7 figures, 1 table
Published: 2011
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160. Very-high-energy gamma-ray emission from the direction of the Galactic globular cluster Terzan 5

Author: HESS Collaboration, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Balzer, A., Barnacka, A., de Almeida, U. Barres, Becherini, Y., Becker, J., Behera, B., Bernloehr, K., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Brucker, J., Brun, F., Brun, P., Bulik, T., Buesching, I., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Cologna, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Atai, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dutson, K., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Foerster, A., Fuessling, M., Gallant, Y. A., Gast, H., Gerard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glueck, B., Goret, P., Goering, D., Haeffner, S., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holler, M., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzynski, K., Katz, U., Kaufmann, S., Keogh, D., Khangulyan, D., Khelifi, B., Klochkov, D., Kluzniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., McComb, T. J. L., Medina, M. C., Mehault, J., Nguyen, N., Moderski, R., Moulin, E., Naumann, C. L., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Wilhelmi, E. de Ona, Opitz, B., Ostrowski, M., Oya, I., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Puehlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schoeck, F. M., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Sikora, M., Skilton, J. L., Sol, H., Spengler, G., Stawarz, L., Steenkamp, R., Stegmann, C., Stinzing, F., Stycz, K., Sushch, I., Szostek, A., Tavernet, J. -P., Terrier, R., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Voelk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., White, R., Wierzcholska, A., Zacharias, M., Zajczyk, A., Zdziarski, A. A., Zech, A., and Zechlin, H. -S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The H.E.S.S. very-high-energy (VHE, E > 0.1 TeV) gamma-ray telescope system has discovered a new source, HESS J1747-248. The measured integral flux is (1.2 +/- 0.3) \times 10^-12 cm-2 s-1 above 440 GeV for a power-law photon spectral index of 2.5 +/- 0.3 stat +/- 0.2 sys. The VHE gamma-ray source is located in the close vicinity of the Galactic globular cluster Terzan 5 and extends beyond the H.E.S.S. point spread function (0.07 degree). The probability of a chance coincidence with Terzan 5 and an unrelated VHE source is quite low (~ 10^-4). With the largest population of identified millisecond pulsars (msPSRs), a very high core stellar density and the brightest GeV range flux as measured by Fermi-LAT, Terzan 5 stands out among Galactic globular clusters. The properties of the VHE source are briefly discussed in the context of potential emission mechanisms, notably in relation to msPSRs. Interpretation of the available data accommodates several possible origins for this VHE gamma-ray source, although none of them offers a satisfying explanation of its peculiar morphology., Comment: 5 pages, 2 figures, accepted for publication in A&A, full author list
Published: 2011
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161. New AGNs discovered by H.E.S.S

Author: Becherini, Y., Behera, B., Biteau, J., Cerruti, M., Giebels, B., Lenain, J. -P., de Naurois, M., Punch, M., Raue, M., Sanchez, D., Volpe, F., and Zech, A.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: During the last year, six new Active Galactic Nuclei (AGN) have been discovered and studied by H.E.S.S. at Very High Energies (VHE). Some of these recent discoveries have been made thanks to new enhanced analysis methods and are presented at this conference for the first time. The three blazars 1ES 0414+009, SHBL J001355.9-185406 and 1RXS J101015.9-311909 have been targeted for observation due to their high levels of radio and X-ray fluxes, while the Fermi/LAT catalogue of bright sources triggered the observation of PKS 0447-439 and AP Librae. Additionally, the BL Lac 1ES 1312-423 was discovered in the field-of-view (FoV) of Centaurus A thanks to the large exposure dedicated by H.E.S.S. to this particularly interesting source. The newly-discovered sources are presented here and in three companion presentations at this conference., Comment: 8 pages, 3 figures, proceeding from the 25th Texas Symposium on Relativistic Astrophysics (Heidelberg, Germany, 2010)
Published: 2011

162. A new SNR with TeV shell-type morphology: HESS J1731-347

Author: HESS Collaboration, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Balzer, A., Barnacka, A., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Borrel, V., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Förster, A., Füßling, M., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Häffner, S., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holler, M., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzynski, K., Katz, U., Kaufmann, S., Keogh, D., Khangulyan, D., Khélifi, B., Klochkov, D., Kluzniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lennarz, D., Löhse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., McComb, T. J. L., Medina, M. C., Méhault, J., Moderski, R., Moulin, E., Naumann, C. L., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-P., Wilhelmi, E. de Oña, Opitz, B., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Sikora, M., Skilton, J. L., Sol, H., Spengle, G., Stawarz, L., Steenkamp, R., Stegmann, C., Stinzing, F., Stycz, K., Sushch, I., Szostek, A., Tavernet, J. -P., Terrier, R., Tibolla3, O., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Vivier, M., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., Wierzcholska, A., Zacharias, M., Zajczyk, A., Zdziarski, A. A., Zech, A., and Zechlin, H. -S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The recent discovery of the radio shell-type supernova remnant (SNR), G353.6-0.7, in spatial coincidence with the unidentified TeV source HESS J1731-347 has motivated further observations of the source with the High Energy Stereoscopic System (H.E.S.S.) Cherenkov telescope array to test a possible association of the gamma-ray emission with the SNR. With a total of 59 hours of observation, representing about four times the initial exposure available in the discovery paper of HESS J1731-347, the gamma-ray morphology is investigated and compared with the radio morphology. An estimate of the distance is derived by comparing the interstellar absorption derived from X-rays and the one obtained from 12CO and HI observations. The deeper gamma-ray observation of the source has revealed a large shell-type structure with similar position and extension (r~0.25{\deg}) as the radio SNR, thus confirming their association. By accounting for the H.E.S.S. angular resolution and projection effects within a simple shell model, the radial profile is compatible with a thin, spatially unresolved, rim. Together with RX J1713.7-3946, RX J0852.0-4622 and SN 1006, HESS J1731-347 is now the fourth SNR with a significant shell morphology at TeV energies. The derived lower limit on the distance of the SNR of 3.2 kpc is used together with radio and X-ray data to discuss the possible origin of the gamma-ray emission, either via inverse Compton scattering of electrons or the decay of neutral pions resulting from proton-proton interaction., Comment: 10 pages, 10 figures, accepted for publication in A&A
Published: 2011
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163. Discovery of VHE emission from PKS 0447-439 with H.E.S.S. and MWL studies

Author: Zech, A., Behera, B., Becherini, Y., Boisson, C., Giebels, B., Hauser, M., Kastendieck, M., Kaufmann, S., Kosack, K., Lenain, J. -P., de Naurois, M., Punch, M., Raue, M., Sol, H., Wagner, S., and collaboration, the H. E. S. S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Very-high energy (VHE) emission has been detected from PKS 0447-439 with the H.E.S.S. Cherenkov telescope array. This blazar is one of the brightest hard-spectrum extragalactic objects in the Fermi bright source list. Its detection with H.E.S.S. triggered Target of Opportunity observations with the Swift and RXTE telescopes, which show rapid flaring in the X-ray band. The spectrum and light curve measured by H.E.S.S. are presented. Along with the Fermi LAT data it is possible to put an upper limit on the redshift of the source. Implications of the flux evolution are discussed briefly., Comment: 6 pages, 5 figures, proceeding from the 25th Texas Symposium on Relativistic Astrophysics (Heidelberg, Germany, 2010)
Published: 2011

164. H.E.S.S. observations of the globular clusters NGC 6388 and M 15 and search for a Dark Matter signal

Author: HESS Collaboration, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Balzer, A., Barnacka, A., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Borrel, V., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Förster, A., Füßling, M., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Häffner, S., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holler, M., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzynski, K., Katz, U., Kaufmann, S., Keogh, D., Khangulyan, D., Khélifi, B., Klochkov, D., Kluzniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lennarz, D., Löhse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., McComb, T. J. L., Medina, M. C., Méhault, J., Moderski, R., Moulin, E., Naumann, C. L., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-P., Wilhelmi, E. de Oña, Opitz, B., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Sikora, M., Skilton, J. L., Sol, H., Spengle, G., Stawarz, L., Steenkamp, R., Stegmann, C., Stinzing, F., Stycz, K., Sushch, I., Szostek, A., Tavernet, J. -P., Terrier, R., Tibolla3, O., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Vivier, M., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., Wierzcholska, A., Zacharias, M., Zajczyk, A., Zdziarski, A. A., Zech, A., and Zechlin, H. -S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Observations of the globular clusters NGC 6388 and M 15 were carried out by the H.E.S.S. array of Cherenkov telescopes for a live time of 27.2 and 15.2 hours respectively. No gamma-ray signal is found at the nominal target position of NGC 6388 and M 15. In the primordial formation scenario, globular clusters are formed in a dark matter halo and dark matter could still be present in the baryon-dominated environment of globular clusters. This opens the possibility of observing a dark matter self-annihilation signal. The dark matter content of the globular clusters NGC 6388 and M 15 is modelled taking into account the astrophysical processes that can be expected to influence the dark matter distribution during the evolution of the globular cluster: the adiabatic contraction of dark matter by baryons, the adiabatic growth of a black hole in the dark matter halo and the kinetic heating of dark matter by stars. 95% confidence level exclusion limits on the dark matter particle velocity-weighted annihilation cross section are derived for these dark matter haloes. In the TeV range, the limits on the velocity-weighted annihilation cross section are derived at the 10-25 cm3 s-1 level and a few 10-24 cm3 s-1 for NGC 6388 and M 15 respectively., Comment: 10 pages, 5 figures, 4 tables, accepted for publication in ApJ
Published: 2011
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165. Search for a Dark Matter annihilation signal from the Galactic Center halo with H.E.S.S

Author: Collaboration, H. E. S. S., Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Barnacka, A., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Borrel, V., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Förster, A., Füßling, M., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzynski, K., Katz, U., Kaufmann, S., Keogh, D., Kerschhaggl, M., Khangulyan, D., Khélifi, B., Klochkov, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C, Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., McComb, T. J. L., Medina, M. C., Méhault, J., Moderski, R., Moulin, E., Naumann, C. L., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-F., Wilhelmi, E. de Oña, Opitz, B., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schönwald, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Shalchi, A., Sikora, M., Skilton, J. L., Sol, H., Spengler, G., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Sushch, I., Szostek, A., Tavernet, J. -P., Terrier, R., Tibolla, O., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Vivier, M., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., Wierzcholska, A., Zajczyk, A., Zdziarski, A. A., Zech, A., and Zechlin, H. -S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology
Abstract: A search for a very-high-energy (VHE; >= 100 GeV) gamma-ray signal from self-annihilating particle Dark Matter (DM) is performed towards a region of projected distance r ~ 45-150 pc from the Galactic Center. The background-subtracted gamma-ray spectrum measured with the High Energy Stereoscopic System (H.E.S.S.) gamma-ray instrument in the energy range between 300 GeV and 30 TeV shows no hint of a residual gamma-ray flux. Assuming conventional Navarro-Frenk-White (NFW) and Einasto density profiles, limits are derived on the velocity-weighted annihilation cross section < \sigma v> as a function of the DM particle mass. These are among the best reported so far for this energy range. In particular, for the DM particle mass of ~1 TeV, values for <\sigma v> above 3 * 10^(-25) cm^3 s^(-1) are excluded for the Einasto density profile. The limits derived here differ much less for the chosen density profile parametrizations, as opposed to limits from gamma-ray observations of dwarf galaxies or the very center of the Milky Way, where the discrepancy is significantly larger., Comment: 6 Pages, accepted for publication in Phys. Rev. Lett
Published: 2011
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166. HESS J1943+213: a candidate extreme BL Lacertae object

Author: Collaboration, H. E. S. S., Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Balzer, A., Barnacka, A., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Borrel, V., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Colom, P., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Förster, A., Füßling, M., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Häffner, S., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holler, M., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzyński, K., Katz, U., Kaufmann, S., Keogh, D., Khangulyan, D., Khélifi, B., Klochkov, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., McComb, T. J. L., Medina, M. C., Méhault, J., Nguyen, N., Moderski, R., Moulin, E., Naumann, C. L., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-F., Wilhelmi, E. de Oña, Opitz, B., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schönwald, A., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Shalchi, A., Sikora, M., Skilton, J. L., Sol, H., Spengler, G., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Stycz, K., Sushch, I., Szostek, A., Tavernet, J. -P., Terrier, R., Tibolla, O., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Vivier, M., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., Wierzcholska, A., Zajczyk, A., Zdziarski, A. A., Zech, A., Zechlin, H. -S., Burnett, T. H., and Hill, A. B.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We report on a newly detected point-like source, HESS J1943+213 located in the Galactic plane. This source coincides with an unidentified hard X-ray source IGR J19443+2117, which was proposed to have radio and infrared counterparts. HESS J1943+213 is detected at the significance level of 7.9 \sigma (post-trials) at RA(J2000)=19h 43m 55s +- 1s (stat) +- 1s (sys), DEC(J2000) = +21deg 18' 8" +- 17" (stat) +- 20" (sys). The source has a soft spectrum with photon index Gamma = 3.1 +- 0.3 (stat) +- 0.2 (sys) and a flux above 470 GeV of 1.3 +- 0.2 (stat) +- 0.3 (sys) x 10^{-12} cm^{-2} s^{-1}. There is no Fermi/LAT counterpart down to a flux limit of 6 x 10^{-9} cm^{-2} s^{-1} in the 0.1-100 GeV energy range (95% confidence upper limit calculated for an assumed power-law model with a photon index Gamma=2.0). The data from radio to VHE gamma-rays do not show any significant variability. We combine new H.E.S.S., Fermi/LAT and Nancay Radio Telescope observations with pre-existing non-simultaneous multi-wavelength observations of IGR J19443+2117 and discuss the likely source associations as well as the interpretation as an active galactic nucleus, a gamma-ray binary or a pulsar wind nebula. The lack of a massive stellar counterpart disfavors the binary hypothesis, while the soft VHE spectrum would be very unusual in case of a pulsar wind nebula. In addition, the distance estimates for Galactic counterparts places them outside of the Milky Way. All available observations favor an interpretation as an extreme, high-frequency peaked BL Lac object with a redshift z>0.14. This would be the first time a blazar is detected serendipitously from ground-based VHE observations, and the first VHE AGN detected in the Galactic Plane., Comment: 10 pages, 7 figures, in press at A&A
Published: 2011
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167. Detection of very-high-energy gamma-ray emission from the vicinity of PSR B1706-44 and G343.1-2.3 with H.E.S.S

Author: Collaboration, H. E. S. S., Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Barnacka, A., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Borrel, V., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Conrad, J., Chounet, L. -M., Clapson, A. C., Coignet, G., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Förster, A., Fontaine, G., Füßling, M., Gabici, S., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holleran, M., Hoppe, S., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzyński, K., Katz, U., Kaufmann, S., Kerschhaggl, M., Khangulyan, D., Khélifi, B., Keogh, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffont, H., Lamanna, G., Lemoine-Goumard, M., Lenain, J. -P., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., McComb, T. J. L., Medina, M. C., Méhault, J., Moderski, R., Moulin, E., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-F., Wilhelmi, E. de Oña, Opitz, B., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schönwald, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Shalchi, A., Sushch, I., Sikora, M., Skilton, J. L., Sol, H., Spengler, G., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Szostek, A., Tam, P. H., Tavernet, J. -P., Terrier, R., Tibolla, O., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Vivier, M., Völk, H. J., Volpe, F., Vorobiov, S., Wagner, S. J., Ward, M., Wierzcholska, A., Zajczyk, A., Zdziarski, A. A., Zech, A., Zechlin, H. -S., Dubner, G., and Giacani, E.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The gamma-ray pulsar PSR B1706-44 and the adjacent supernova remnant (SNR) candidate G343.1-2.3 were observed by H.E.S.S. during a dedicated observation campaign in 2007. As a result of this observation campaign, a new source of very-high-energy (VHE; E > 100 GeV) gamma-ray emission, HESS J1708-443, was detected with a statistical significance of 7 sigma, although no significant point-like emission was detected at the position of the energetic pulsar itself. In this paper, the morphological and spectral analyses of the newly-discovered TeV source are presented. The centroid of HESS J1708-443 is considerably offset from the pulsar and located near the apparent center of the SNR, at RA(J2000) = 17h08m11s +/- 17s and Dec(J2000) = -44d20' +/- 4'. The source is found to be significantly more extended than the H.E.S.S. point spread function (~0.1 deg), with an intrinsic Gaussian width of 0.29 deg +/- 0.04 deg. Its integral flux between 1 and 10 TeV is ~ 3.8 x 10^-12 ph cm^-2 s^-1, equivalent to 17% of the Crab Nebula flux in the same energy range. The measured energy spectrum is well-fit by a power law with a relatively hard photon index Gamma = 2.0 +/- 0.1 (stat) +/- 0.2 (sys). Additional multi-wavelength data, including 330 MHz VLA observations, were used to investigate the VHE gamma-ray source's possible associations with the pulsar wind nebula of PSR B1706-44 and/or with the complex radio structure of the partial shell-type SNR G343.1-2.3., Comment: 15 pages, 6 figures, 3 tables; Accepted for publication in A&A; v2 paper remains the same, but all authors are now explicitly listed in arXiv entry
Published: 2011
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168. Search for Lorentz Invariance breaking with a likelihood fit of the PKS 2155-304 flare data taken on MJD 53944

Author: HESS Collaboration, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Barnacka, A., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Borrel, V., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Bühler, R., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Frster, A., Fontaine, G., Füßling, M., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzyński, K., Katz, U., Kaufmann, S., Keogh, D., Kerschhaggl, M., Khangulyan, D., Khélifi, B., Klochkov, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., McComb, T. J. L., Medina, M. C., Méhault, J., Moderski, R., Moulin, E., Naumann, C. L., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-F., Wilhelmi, E. de Oña, Opitz, B., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti1, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schönwald, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Shalchi, A., Sikora, M., Skilton, J. L., Sol, H., Spengler, G., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Sushch, I., Szostek, A., Tavernet, J. -P., Terrier, R., Tibolla, O., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Vivier, M., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., Wierzcholska, A., Zajczyk, A., Zdziarski, A. A., Zech, A., and Zechlin, H. -S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, General Relativity and Quantum Cosmology
Abstract: Several models of Quantum Gravity predict Lorentz Symmetry breaking at energy scales approaching the Planck scale (10^{19} GeV). With present photon data from the observations of distant astrophysical sources, it is possible to constrain the Lorentz Symmetry breaking linear term in the standard photon dispersion relations. Gamma-ray Bursts (GRB) and flaring Active Galactic Nuclei (AGN) are complementary to each other for this purpose, since they are observed at different distances in different energy ranges and with different levels of variability. Following a previous publication of the High Energy Stereoscopic System (H.E.S.S.) collaboration, a more sensitive event-by-event method consisting of a likelihood fit is applied to PKS 2155-304 flare data of MJD 53944 (July 28, 2006) as used in the previous publication. The previous limit on the linear term is improved by a factor of ~3 up to M^{l}_{QG} > 2.1x10^{18} GeV and is currently the best result obtained with blazars. The sensitivity to the quadratic term is lower and provides a limit of M^{q}_{QG} > 6.4x10^10 GeV, which is the best value obtained so far with an AGN and similar to the best limits obtained with GRB., Comment: 24 pages, 9 figures. Accepted for publication in Astropart. Phys. Rev1 is the final accepted version (typo corrections)
Published: 2011
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169. H.E.S.S. constraints on Dark Matter annihilations towards the Sculptor and Carina Dwarf Galaxies

Author: HESS Collaboration, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Barnacka, A., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Borrel, V., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Frster, A., Fontaine, G., Füßling, M., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzyński, K., Katz, U., Kaufmann, S., Keogh, D., Kerschhaggl, M., Khangulyan, D., Khélifi, B., Klochkov, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., McComb, T. J. L., Medina, M. C., Méhault, J., Moderski, R., Moulin, E., Naumann, C. L., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-F., Wilhelmi, E. de Oña, Opitz, B., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti1, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schönwald, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Shalchi, A., Sikora, M., Skilton, J. L., Sol, H., Spengler, G., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Sushch, I., Szostek, A., Tavernet, J. -P., Terrier, R., Tibolla, O., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Vivier, M., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., Wierzcholska, A., Zajczyk, A., Zdziarski, A. A., Zech, A., and Zechlin, H. -S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The Sculptor and Carina Dwarf spheroidal galaxies were observed with the H.E.S.S. Cherenkov telescope array between January 2008 and December 2009. The data sets consist of a total of 11.8 and 14.8 hours of high quality data, respectively. No gamma-ray signal was detected at the nominal positions of these galaxies above 220 GeV and 320 GeV, respectively. Upper limits on the gamma-ray fluxes at 95% C.L. assuming two forms for the spectral energy distribution (a power law shape and one derived from dark matter annihilation) are obtained at the level of 10^-13 to 10^-12 cm^-2s^-1 in the TeV range. Constraints on the velocity weighted dark matter particle annihilation cross section for both Sculptor and Carina dwarf galaxies range from <\sigma v> ~ 10^-21 cm^3s^-1 down to <\sigma v> ~ 10^-22 cm^3s^-1 depending on the dark matter halo model used. Possible enhancements of the gamma-ray flux are studied: the Sommerfeld effect, which is found to exclude some dark matter particle masses, the internal Bremsstrahlung and clumps in the dark-matter halo distributions., Comment: Accepted for publication on Astroparticle Physics, 25 pages, 12 figures
Published: 2010
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170. Discovery and follow-up studies of the extended, off-plane, VHE gamma-ray source HESS J1507-622

Author: Collaboration, H. E. S. S., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Behera, B., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Borrel, V., Brucker, J., Brun, F., Brun, P., Bühler, R., Bulik, T., Büsching, I., Boutelier, T., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Emmanoulopoulos, D., Espigat, P., Farnier, C., Feinstein, F., Fiasson, A., Förster, A., Fontaine, G., Füssling, M., Gabici, S., Gallant, Y. A., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück16, B., Goret, P., Göring, D., Hauser, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Holleran, M., Hoppe, S., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jung, I., Katarzyński, K., Katz, U., Kaufmann, S., Kerschhaggl, M., Khangulyan, D., Khélifi, B., Keogh, D., Klochkov, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Lamanna, G., Lenain, J. -P., Lohse, T., Marandon, V., Martineau-Huynh, O., Marcowith, A., Masbou, J., Maurin, D., McComb, T. J. L., Medina, M. C., Méhault, J., Moderski, R., Moulin, E., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-F., Wilhelmi, E. de Oña, Orford, K. J., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raubenheimer, B. C., Raue, M., Rayner, S. M., Reimer, O., Renaud, M., Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schwanke, U., Schwarzburg, S., Schwemmer, S., Shalchi, A., Sikora, M., Skilton, J. L., Sol, H., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Superina, G., Szostek, A., Tam, P. H., Tavernet, J. -P., Terrier, R., Tibolla, O., Tluczykont, M., van Eldik, C., Vasileiadis, G., Venter, C., Venter, L., Vialle, J. P., Vincent, P., Vivier, M., Völk, H. J., Volpe, F., Wagner, S. J., Ward, M., Zdziarski, A. A., and Zech, A.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Context: The detection of gamma-rays in the very-high-energy (VHE) range (100 GeV-100 TeV) offers the possibility of studying the parent population of ultrarelativistic particles found in astrophysical sources, so it is useful for understanding the underlying astrophysical processes in nonthermal sources. Aim: The discovery of the VHE gamma-ray source HESS J1507-622 is reported and possibilities regarding its nature are investigated. Methods: The H.E.S.S. array of imaging atmospheric Cherenkov telescopes (IACTs) has a high sensitivity compared with previous instruments (~1% of the Crab flux in 25 hours observation time for a 5 sigma point-source detection) and has a large field of view (~5 deg in diameter). HESS J1507-622 was discovered within the ongoing H.E.S.S. survey of the inner Galaxy, and the source was also studied by means of dedicated multiwavelength observations. Results: A Galactic gamma-ray source, HESS J1507-622, located ~3.5 deg from the Galactic plane was detected with a statistical significance > 9 sigma. Its energy spectrum is well fitted by a power law with spectral index \Gamma = 2.24 +/- 0.16_{stat} +/- 0.20_{sys} and a flux above 1 TeV of (1.5 +/- 0.4_{stat} +/- 0.3_{sys}) X 10^{-12} cm^{-2} s^{-1}. Possible interpretations (considering both hadronic and leptonic models) of the VHE gamma-ray emission are discussed in the absence of an obvious counterpart., Comment: Accepted for publication in A&A
Published: 2010
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171. Revisiting the Westerlund 2 Field with the H.E.S.S. Telescope Array

Author: The HESS Collaboration, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Barnacka, A., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Borrel, V., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Boutelier, T., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Conrad, J., Chounet, L. -M., Clapson, A. C., Coignet, G., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Förster, A., Fontaine, G., Füßling, M., Gabici, S., Gallant, Y. A., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holleran, M., Hoppe, S., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jung, I., Katarzyński, K., Katz, U., Kaufmann, S., Kerschhaggl, M., Khangulyan, D., Khélifi, B., Keogh, D., Klochkov, D., Kluźniak24, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Lamanna, G., Lenain, J. -P., Lennarz, D., Lohse, T., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., McComb, T. J. L., Medina, M. C., Méhault, J., Moderski, R., Moulin, E., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-F., Wilhelmi, E. de Oña, Opitz, B., Orford, K. J., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti1, G., Pelletier, G., Petrucci, P. -O., Pita1, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger1, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schönwald, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Shalchi, A., Sushch, I., Sikora, M., Skilton, J. L., Sol, H., Spengler, G., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Szostek, A., Tam, P. H., Tavernet, J. -P., Terrier, R., Tibolla, O., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Vivier, M., Völk, H. J., Volpe, F., Vorobiov, S., Wagner, S. J., Ward, M., Zdziarski, A. A., Zech, A., Zechlin, H. -S., Fukui, Y., Furukawa, N., Ohama, A., Sano, H., Dawson, J., and Kawamura, A.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Aims. Previous observations with the H.E.S.S. telescope array revealed the existence of extended very-high-energy (VHE; E>100 GeV) {\gamma}-ray emission, HESS J1023-575, coincident with the young stellar cluster Westerlund 2. At the time of discovery, the origin of the observed emission was not unambiguously identified, and follow-up observations have been performed to further investigate the nature of this {\gamma}-ray source. Methods. The Carina region towards the open cluster Westerlund 2 has been re-observed, increasing the total exposure to 45.9 h. The combined dataset includes 33 h of new data and now permits a search for energy-dependent morphology and detailed spectroscopy. Results. A new, hard spectrum VHE {\gamma}-ray source, HESSJ1026-582, was discovered with a statistical significance of 7{\sigma}. It is positionally coincident with the Fermi LAT pulsar PSR J1028-5819. The positional coincidence and radio/{\gamma}-ray characteristics of the LAT pulsar favors a scenario where the TeV emission originates from a pulsar wind nebula. The nature of HESS J1023-575 is discussed in light of the deep H.E.S.S. observations and recent multi-wavelength discoveries, including the Fermi LAT pulsar PSRJ1022-5746 and giant molecular clouds in the region. Despite the improved VHE dataset, a clear identification of the object responsible for the VHE emission from HESS J1023-575 is not yet possible, and contribution from the nearby high-energy pulsar and/or the open cluster remains a possibility., Comment: Accepted for publication on A&A
Published: 2010
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172. Discovery of VHE gamma-rays from the BL Lac object PKS 0548-322

Author: collaboration, H. E. S. S., Aharonian, F., Akhperjanian, A. G., Anton, G., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Behera, B., Benbow, W., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Borrel, V., Brucker, J., Brun, F., Brun, P., Bühler, R., Bulik, T., Büsching, I., Boutelier, T., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Emmanoulopoulos, D., Espigat, P., Farnier, C., Feinstein, F., Fiasson, A., Förster, A., Fontaine, G., Füssling, M., Gabici, S., Gallant, Y. A., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Hauser, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Holleran, M., Hoppe, S., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jung, I., Katarzyński, K., Katz, U., Kaufmann, S., Kendziorra, E., Kerschhagg, M., Khangulyan, D., Khélifi, B., Keogh, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Lamanna, G., Lenain, J. -P., Lohse, T., Marandon, V., Martin, J. M., Martineau-Huynh, O., Marcowith, A., Masbou, J., Maurin, D., McComb, T. J. L., Medina, M. C., Moderski, R., Moulin, E., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-F., Wilhelm, E. de Oña, Orford, K. J., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raubenheimer, B. C., Raue, M., Rayner, S. M., Renaud, M., Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schröder, R., Schwanke, U., Schwarzburg, S., Schwemmer, S., Shalchi, A., Sikora, M., Skilton, J. L., Sol, H., Spangler, D., Stawarz, L., Steenkamp, R., Stegmann, C., Stinzing, F., Superina, G., Szostek, A., Tam, P. H., Tavernet, J. -P., Terrier, R., Tibolla, O., Tluczykont, M., van Eldik, C., Vasileiadis, G., Venter, C., Venter, L., Vialle, J. P., Vincent, P., Vivier, M., Völk, H. J., Volp, F., Wagner, S. J., Ward, M., Zdziarski, A. A., and Zech, A.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: PKS 0548-322 (z=0.069) is a ``high-frequency-peaked'' BL Lac object and a candidate very high energy (VHE, E>100 GeV) gamma-ray emitter, due to its high X-ray and radio flux. Observations at the VHE band provide insights into the origin of very energetic particles present in this source and the radiation processes at work. We report observations made between October 2004 and January 2008 with the H.E.S.S. array, a four imaging atmospheric-Cherenkov telescopes. Contemporaneous UV and X-ray observations with the Swift satellite in November 2006 are also reported. PKS 0548-322 is detected for the first time in the VHE band with H.E.S.S. We measure an excess of 216 gamma-rays corresponding to a significance of 5.6 standard deviations. The photon spectrum of the source is described by a power-law, with a photon index of Gamma=2.86 +/- 0.34 (stat) +/- 0.10 (sys). The integral flux above 200 GeV is 1.3 % of the flux of the Crab Nebula, and is consistent with being constant in time. Contemporaneous Swift/XRT observations reveal an X-ray flux between 2 and 10 keV of F_{2-10 keV}=2.3 +/- 0.2 x 10^{-11} erg.cm^{-2}. s^{-1}, an intermediate intensity state with respect to previous observations. The spectral energy distribution can be reproduced using a simple one-zone synchrotron self Compton model, with parameters similar those observed for other sources of this type., Comment: 6 pages, 3 figures, Accepted for publication in Astronomy and Astrophysics
Published: 2010
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173. VHE gamma-ray emission of PKS 2155-304: spectral and temporal variability

Author: HESS Collaboration, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Behera, B., Benbow, W., Bernlohr, K., Bochow, A., Boisson, C., Bolmont, J., Borrel, V., Brucker, J., Brun, F., Brun, P., Buhler, R., Bulik, T., Busching, I., Boutelier, T., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Conrad, J., Chounet, L. -M., Clapson, A. C., Coignet, G., Costamante, L., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Atai, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Foerster, A., Fontaine, G., Fussling, M., Gabici, S., Gallant, Y. A., Gerard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glueck, B., Goret, P., Goering, D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holleran, M., Hoppe, S., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jung, I., Katarzynski, K., Katz, U., Kaufmann, S., Kerschhaggl, M., Khangulyan, D., Khelifi, B., Keogh, D., Klochkov, D., Kluzniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Lamanna, G., Lenain, J. -P., Lohse, T., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., McComb, T. J. L., Medina, M. C., Mehault, J., Moderski, R., Moulin, E., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-F., Wilhelmi, E. de Ona, Opitz, B., Orford, K. J., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Puehlhofer, G., Punch, M., Quirrenbach, A., Raubenheimer, B. C., Raue, M., Rayner, S. M., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schoeck, F. M., Schoenwald, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Shalchi, A., Sushch, I., Sikora, M., Skilton, J. L., Sol, H., Stawarz, L., Steenkamp, R., Stegmann, C., Stinzing, F., Superina, G., Szostek, A., Tam, P. H., Tavernet, J. -P., Terrier, R., Tibolla, O., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Venter, L., Vialle, J. P., Viana, A., Vincent, P., Vivier, M., Voelk, H. J., Volpe, F., Vorobiov, S., Wagner, S. J., Ward, M., Zdziarski, A. A., Zech, A., and Zechlin, H. -S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Observations of very high energy gamma-rays from blazars provide information about acceleration mechanisms occurring in their innermost regions. Studies of variability in these objects allow a better understanding of the mechanisms at play. To investigate the spectral and temporal variability of VHE (>100 GeV) gamma-rays of the well-known high-frequency-peaked BL Lac object PKS 2155-304 with the H.E.S.S. imaging atmospheric Cherenkov telescopes over a wide range of flux states. Data collected from 2005 to 2007 are analyzed. Spectra are derived on time scales ranging from 3 years to 4 minutes. Light curve variability is studied through doubling timescales and structure functions, and is compared with red noise process simulations. The source is found to be in a low state from 2005 to 2007, except for a set of exceptional flares which occurred in July 2006. The quiescent state of the source is characterized by an associated mean flux level of 4.32 +/-0.09 x 10^-11 cm^-2 s^-1 above 200 GeV, or approximately 15% of the Crab Nebula, and a power law photon index of 3.53 +/-0.06. During the flares of July 2006, doubling timescales of ~2 min are found. The spectral index variation is examined over two orders of magnitude in flux, yielding different behaviour at low and high fluxes,which is a new phenomenon in VHE gamma-ray emitting blazars. The variability amplitude characterized by the fractional r.m.s. is strongly energy-dependent and is proportional to E^(0.19 +/- 0.01). The light curve r.m.s. correlates with the flux. This is the signature of a multiplicative process which can be accounted for as a red noise with a Fourier index of ~2. This unique data set shows evidence for a low level gamma-ray emission state from PKS 2155-304, which possibly has a different origin than the outbursts. The discovery of the light curve lognormal behaviour might be an indicator .., Comment: 17 pages, 13 figures, Accepted for publication to Astronomy & Astrophysics
Published: 2010
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174. First detection of VHE gamma-rays from SN 1006 by H.E.S.S

Author: HESS Collaboration, Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Behera, B., Beilicke, M., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Borrel, V., Brucker, J., Brun, F., Brun, P., Bühler, R., Bulik, T., Büsching, I., Boutelier, T., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Conrad, J., Chounet, L. -M., Clapson, A. C., Coignet, G., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fiasson, A., Förster, A., Fontaine, G., Füßling, M., Gabici, S., Gallant, Y. A., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Hauser, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holleran, M., Hoppe, S., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jung, I., Katarzy'nski, K., Katz, U., Kaufmann, S., Kerschhaggl, M., Khangulyan, D., Khélifi, B., Keogh, D., Klochkov, D., Klu'zniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Lamanna, G., Lemoine-Goumard, M., Lenain, J. -P., Lohse, T., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., McComb, T. J. L., Medina, M. C., Méhault, J., Moulin, E., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-F., Orford, E. de Ona Wilhelmi K. J., Ostrowski, M., Panter, M., Pedaletti, M. Paz Arribas G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, 12 G., Punch, M., Quirrenbach, A., Raubenheimer, B. C., Raue, M., Rayner, S. M., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schönwald, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Shalchi, A., Sushch, I., Sikora, M., Skilton, J. L., Sol, H., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Superina, G., Szostek, A., Tam, P. H., Tavernet, J. -P., Terrier, R., Tibolla, O., Tluczykont, M., van Eldik, C., Vasileiadis, G., Venter, C., Venter, L., Vialle, J. P., Vincent, P., Vink, J., Vivier, M., Völk, H. J., Volpe, F., Vorobiov, S., Wagner, S. J., Ward, M., Zdziarski, A. A., and Zech, A.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Galaxy Astrophysics
Abstract: Recent theoretical predictions of the lowest very high energy (VHE) luminosity of SN 1006 are only a factor 5 below the previously published H.E.S.S. upper limit, thus motivating further in-depth observations of this source. Deep observations at VHE energies (above 100 GeV) were carried out with the High Energy Stereoscopic System (H.E.S.S.) of Cherenkov Telescopes from 2003 to 2008. More than 100 hours of data have been collected and subjected to an improved analysis procedure. Observations resulted in the detection of VHE gamma-rays from SN 1006. The measured gamma-ray spectrum is compatible with a power-law, the flux is of the order of 1% of that detected from the Crab Nebula, and is thus consistent with the previously established H.E.S.S. upper limit. The source exhibits a bipolar morphology, which is strongly correlated with non-thermal X-rays. Because the thickness of the VHE-shell is compatible with emission from a thin rim, particle acceleration in shock waves is likely to be the origin of the gamma-ray signal. The measured flux level can be accounted for by inverse Compton emission, but a mixed scenario that includes leptonic and hadronic components and takes into account the ambient matter density inferred from observations also leads to a satisfactory description of the multi-wavelength spectrum., Comment: 7 pages, 8 figures, accepted for publication in A&A
Published: 2010
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175. Multi-wavelength Observations of H 2356-309

Author: HESS Collaboration, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Behera, B., Benbow, W., Bernloehr, K., Bochow, A., Boisson, C., Bolmont, J., Borrel, V., Brucker, J., Brun, F., Brun, P., Buehler, R., Bulik, T., Buesching, I., Boutelier, T., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Conrad, J., Chounet, L. -M., Clapson, A. C., Coignet, G., Costamante, L., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Atai, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Foerster, A., Fontaine, G., Fuessling, M., Gabici, S., Gallant, Y. A., Gerard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glueck, B., Goret, P., Goering, D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Holleran, M., Hoppe, S., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jung, I., Katarzynski, K., Katz, U., Kaufmann, S., Kerschhaggl, M., Khangulyan, D., Khelifi, B., Keogh, D., Klochkov, D., Kluzniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Lamanna, G., Lenain, J. -P., Lohse, T., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., McComb, T. J. L., Medina, M. C., Mehault, J., Moderski, R., Moulin, E., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nguyen, N., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-F., Wilhelmi, E. de Ona, Opitz, B., Orford, K. J., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Puehlhofer, G., Punch, M., Quirrenbach, A., Raubenheimer, B. C., Raue, M., Rayner, S. M., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schoeck, F. M., Schoenwald, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Shalchi, A., Sushch, I., Sikora, M., Skilton, J. L., Sol, H., Stawarz, L., Steenkamp, R., Stegmann, C., Stinzing, F., Szostek, A., Tam, P. H., Tavernet, J. -P., Terrier, R., Tibolla, O., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Venter, L., Vialle, J. P., Viana, A., Vincent, P., Vivier, M., Voelk, H. J., Volpe, F., Vorobiov, S., Wagner, S. J., Ward, M., Zdziarski, A. A., Zech, A., and Zechlin, H. -S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: AIMS: The properties of the broad-band emission from the high-frequency peaked BL Lac H 2356-309 (z=0.165) are investigated. METHODS: Very High Energy (VHE; E > 100 GeV) observations of H 2356-309 were performed with the High Energy Stereoscopic System (HESS) from 2004 through 2007. Simultaneous optical/UV and X-ray observations were made with the XMM-Newton satellite on June 12/13 and June 14/15, 2005. NRT radio observations were also contemporaneously performed in 2005. ATOM optical monitoring observations were also made in 2007. RESULTS: A strong VHE signal, ~13 sigma total, was detected by HESS after the four years HESS observations (116.8 hrs live time). The integral flux above 240 GeV is I(>240 GeV) = (3.06 +- 0.26 {stat} +- 0.61 {syst}) x 10^{-12} cm^{-2} s^{-1}, corresponding to ~1.6% of the flux observed from the Crab Nebula. A time-averaged energy spectrum is measured from 200 GeV to 2 TeV and is characterized by a power law (photon index of Gamma = 3.06 +- 0.15 {stat} +- 0.10 {syst}). Significant small-amplitude variations in the VHE flux from H 2356-309 are seen on time scales of months and years, but not on shorter time scales. No evidence for any variations in the VHE spectral slope are found within these data. The XMM-Newton X-ray measurements show a historically low X-ray state, characterized by a hard, broken-power-law spectrum on both nights. CONCLUSIONS: The broad-band spectral energy distribution (SED) of the blazar can be adequately fit using a simple one-zone synchrotron self-Compton (SSC) model. In the SSC scenario, higher VHE fluxes could be expected in the future since the observed X-ray flux is at a historically low level., Comment: 11 pages; 13 figures; Accepted for publication in Astronomy & Astrophysics; Figure 8 (SED) updated from V1 to have erroneously plotted optical point (without host galaxy subtracted) removed.
Published: 2010
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176. H.E.S.S. VHE gamma-ray observations of the microquasar GRS 1915+105

Author: Szostek, A., Dubus, G., Brun, F., and de Naurois, M.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: GRS 1915+105 is a very well studied microquasar with a wide variety of temporal and spectral states. Multi-wavelength observations from radio to X-rays have uncovered clear relations between the variability in different bands. GRS 1915+105 is also well-known as a source of superluminal jets moving away from the core with true velocity <=0.9c. Non-thermal emission from the jets or their termination shock could extend to the VHE gamma-ray domain. GRS 1915+105 was observed with the H.E.S.S. telescope array between 2004 and 2008 for a total of 24 hours. We report on these observations and discuss our findings., Comment: 3 pages, 2 figures, Contribution to the 31st ICRC, Lodz, Poland, July 2009
Published: 2009

177. Discovery of VHE gamma-rays from Centaurus A

Author: Raue, M., Lenain, J. -P., Aharonian, F. A., Becherini, Y., Boisson, C., Clapson, A. -C., Costamante, L., Gerard, L., Medina, C., de Naurois, M., Punch, M., Rieger, F., Sol, H., Stawarz, L., and Zech, A.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We report the discovery of faint very high energy (VHE, E > 100 GeV) gamma-ray emission from the radio galaxy Centaurus A in deep observations performed with the H.E.S.S. experiment. A signal with a statistical significance of 5.0 sigma is detected from the region including the radio core and the inner kpc jets. The integral flux above an energy threshold of ~250 GeV is measured to be 0.8% of the flux of the Crab Nebula and the spectrum can be described by a power law with a photon index of 2.7 +/- 0.5_stat +/- 0.2_sys. No significant flux variability is detected in the data set. The discovery of VHE gamma-ray emission from Centaurus A reveals particle acceleration in the source to >TeV energies and, together with M 87, establishes radio galaxies as a class of VHE emitters., Comment: 4 pages, 3 figures, submitted as proceeding to the 44th Recontre de Moriond "Very High Energy Phenomena in the Universe", contains an updated SED including the recent Fermi data
Published: 2009

178. H.E.S.S. observations of galaxy clusters

Author: Domainko, W., Benbow, W., Hinton, J. A., Martineau-Huynh, O., de Naurois, M., Nedbal, D., Pedaletti, G., and Rowell, G.
Subjects: Astrophysics
Abstract: Clusters of galaxies, the largest gravitationally bound objects in the universe, are expected to contain a significant population of hadronic and leptonic cosmic rays. Potential sources for these particles are merger and accretion shocks, starburst driven galactic winds and radio galaxies. Furthermore, since galaxy clusters confine cosmic ray protons up to energies of at least 1 PeV for a time longer than the Hubble time they act as storehouses and accumulate all the hadronic particles which are accelerated within them. Consequently clusters of galaxies are potential sources of VHE (> 100 GeV) gamma rays. Motivated by these considerations, promising galaxy clusters are observed with the H.E.S.S. experiment as part of an ongoing campaign. Here, upper limits for the VHE gamma ray emission for the Abell 496 and Coma cluster systems are reported., Comment: Contribution to the 30th ICRC, Merida Mexico, July 2007
Published: 2007

179. Towards the European strategy for particle physics: the Briefing Book

Author: Akesson, T., Aleksan, R., Allanach, B., Bertolucci, S., Blondel, A., Butterworth, J., Cavalli-Sforza, M., Cervera, A., Davidson, S., de Naurois, M., Desch, K., Egede, U., Glover, N., Heuer, R., Hoecker, A., Huber, P., Jungmann, K., Landua, R., Goff, J-M. Le, Linde, F., Lombardi, A., Mangano, M., Mezzetto, M., Onderwater, G., Palanque-Delabrouille, N., Peach, K., Polosa, A., Rondio, E., Webber, B., Weiglein, G., Womersley, J., and Wurr, K.
Subjects: High Energy Physics - Phenomenology, High Energy Physics - Experiment, High Energy Physics - Theory
Abstract: This document was prepared as part of the briefing material for the Workshop of the CERN Council Strategy Group, held in DESY Zeuthen from 2nd to 6th May 2006. It gives an overview of the physics issues and of the technological challenges that will shape the future of the field, and incorporates material presented and discussed during the Symposium on the European Strategy for Particle Physics, held in Orsay from 30th January to 2nd February 2006, reflecting the various opinions of the European community as recorded in written submissions to the Strategy Group and in the discussions at the Symposium., Comment: 199 pages, PDF file
Published: 2006
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180. Measurement of the Crab Flux Above 60 GeV with the CELESTE Cherenkov Telescope

Author: De Naurois, M., Holder, J., Bazer-Bachi, R., Bergeret, H., Bruel, P., Cordier, A., Debiais, G., Dezalay, J-P., Dumora, D., Durand, E., Eschstruth, P., Espigat, P., Fabre, B., Fleury, P., Herault, N., Hrabovsky, M., Incerti, S., Gallou, R. Le, Munz, F., Musquere, A., Olive, J-F., Pare, E., Quebert, J., Rannot, R. C., Reposeur, T., Rob, L., Roy, P., Sako, T., Schovanek, P., Smith, D. A., Snabre, P., and Volte, A.
Subjects: Astrophysics
Abstract: We have converted the former solar electrical plant THEMIS (French Pyrenees) into an atmospheric Cherenkov detector called CELESTE, which records gamma rays above 30 GeV (7E24 Hz). Here we present the first sub-100 GeV detection by a ground based telescope of a gamma ray source, the Crab nebula, in the energy region between satellite measurements and imaging atmospheric Cherenkov telescopes. At our analysis threshold energy of 60 +/- 20 GeV we measure a gamma ray rate of 6.1 +/- 0.8 per minute. Allowing for 30% systematic uncertainties and a 30% error on the energy scale yields an integral gamma ray flux of I(E>60 GeV) = 6.2^{+5.3}_{-2.3} E-6 photons m^-2 s^-1. The analysis methods used to obtain the gamma ray signal from the raw data are detailed. In addition, we determine the upper limit for pulsed emission to be <12% of the Crab flux at the 99% confidence level, in the same energy range. Our result indicates that if the power law observed by EGRET is attenuated by a cutoff of form e^{-E/E_0} then E_0 < 26 GeV. This is the lowest energy probed by a Cherenkov detector and leaves only a narrow range unexplored beyond the energy range studied by EGRET., Comment: 34 pages, accepted by the Astrophysical Journal
Published: 2001
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181. Status and Current Sensitivity of the CELESTE Experiment

Author: de Naurois, M. and collaboration, CELESTE
Subjects: Astrophysics
Abstract: The CELESTE experiment uses the heliostats of an old solar farm in the French Pyrenees to detect gamma ray air showers by the atmospheric Cerenkov technique. CELESTE has been operating since November 1999 with an array of 40 heliostats fully instrumented with 1GHz flash ADCs. Significant advances have been made in the detector simulations and in the data analysis techniques. We report here on results from recent observations of the Crab nebula above an energy threshold of 50GeV. The results and simulations illustrate the current sensitivity of the experiment., Comment: 4 pages, 6 figures. To appear in the Proceedings of the Heidelberg Gamma Ray Symposium
Published: 2000
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182. Discovery of Very High Energy Gamma Rays Associated with an X-ray Binary

Author: Aharonian, F., Akhperjanian, A. G., Bazer-Bachi, A. R., Beilicke, M., Benbow, W., Berge, D., Berghaus, P., Bernlöhr, K., Boisson, C., Bolz, O., Borrel, V., Braun, I., Breitling, F., Brown, A. M., Gordo, J. Bussons, Chadwick, P. M., Cornils, R., Costamante, L., Degrange, B., Dickinson, H. J., Djannati-Ataï, A., Dubus, G., Emmanoulopoulos, D., Espigat, P., Feinstein, F., Fleury, P., Fontaine, G., Fuchs, Y., Funk, S., Gallant, Y. A., Giebels, B., Gillessen, S., Glicenstein, J. F., Goret, P., Hadjichristidis, C., Hauser, M., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hofmann, W., Holleran, M., Horns, D., Jacholkowska, A., de Jager, O. C., Khélifi, B., Konopelko, A., Latham, I. J., Le Gallou, R., Lemière, A., Lemoine-Goumard, M., Leroy, N., Lohse, T., Marcowith, A., Martineau-Huynh, O., Masterson, C., McComb, T. J. L., de Naurois, M., Nolan, S. J., Noutsos, A., Orford, K. J., Osborne, J. L., Ouchrif, M., Panter, M., Pelletier, G., Pita, S., Pühlhofer, G., Punch, M., Raubenheimer, B. C., Raue, M., Raux, J., Rayner, S. M., Reimer, A., Reimer, O., Ripken, J., Rob, L., Rolland, L., Rowell, G., Sahakian, V., Saugé, L., Schlenker, S., Schlickeiser, R., Schuster, C., Schwanke, U., Siewert, M., Sol, H., Spangler, D., Steenkamp, R., Stegmann, C., Terrier, R., Théoret, C. G., Tluczykont, M., Vasileiadis, G., Venter, C., Vincent, P., Völk, H. J., and Wagner, S. J.
Published: 2005

183. A New Population of Very High Energy Gamma-Ray Sources in the Milky Way

Author: Aharonian, F., Akhperjanian, A. G., Bazer-Bachi, A. R., Beilicke, M., Benbow, W., Berge, D., Berghaus, P., Bernlöhr, K., Boisson, C., Bolz, O., Borgmeier, C., Braun, I., Breitling, F., Brown, A. M., Gordo, J. Bussons, Chadwick, P. M., Cornils, R., Costamante, L., Degrange, B., Djannati-Ataï, A., Dubus, G., Ergin, T., Espigat, P., Feinstein, F., Fleury, P., Fontaine, G., Funk, S., Gallant, Y. A., Giebels, B., Gillessen, S., Goret, P., Hadjichristidis, C., Hauser, M., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hofmann, W., Holleran, M., Horns, D., de Jager, O. C., Jung, I., Khélifi, B., Konopelko, A., Latham, I. J., Le Gallou, R., Lemière, A., Lemoine, M., Leroy, N., Lohse, T., Marcowith, A., Masterson, C., McComb, T. J. L., de Naurois, M., Nolan, S. J., Noutsos, A., Orford, K. J., Osborne, J. L., Ouchrif, M., Panter, M., Pelletier, G., Pita, S., Pühlhofer, G., Punch, M., Raubenheimer, B. C., Raue, M., Raux, J., Rayner, S. M., Redondo, I., Reimer, A., Reimer, O., Ripken, J., Rob, L., Rolland, L., Rowell, G., Sahakian, V., Saugé, L., Schlenker, S., Schlickeiser, R., Schuster, C., Schwanke, U., Siewert, M., Sol, H., Steenkamp, R., Stegmann, C., Terrier, R., Théoret, C. G., Tluczykont, M., van der Walt, D. J., Vasileiadis, G., Venter, C., Vincent, P., Visser, B., Völk, H. J., and Wagner, S. J.
Published: 2005

184. The Vanishing of the Primary Emission Region in PKS 1510–089

Author: Aharonian, F., primary, Benkhali, F. Ait, additional, Aschersleben, J., additional, Ashkar, H., additional, Backes, M., additional, Martins, V. Barbosa, additional, Barnard, J., additional, Batzofin, R., additional, Becherini, Y., additional, Berge, D., additional, Bernlöhr, K., additional, Bi, B., additional, de Bony de Lavergne, M., additional, Böttcher, M., additional, Boisson, C., additional, Bolmont, J., additional, Borowska, J., additional, Bouyahiaoui, M., additional, Bradascio, F., additional, Breuhaus, M., additional, Brose, R., additional, Brown, A. M., additional, Brun, F., additional, Bruno, B., additional, Bulik, T., additional, Burger-Scheidlin, C., additional, Caroff, S., additional, Casanova, S., additional, Cecil, R., additional, Celic, J., additional, Cerruti, M., additional, Chand, T., additional, Chandra, S., additional, Chen, A., additional, Chibueze, J., additional, Chibueze, O., additional, Cotter, G., additional, Damascene Mbarubucyeye, J., additional, Davids, I. D., additional, Djannati-Ataï, A., additional, Dmytriiev, A., additional, Doroshenko, V., additional, Egberts, K., additional, Einecke, S., additional, Ernenwein, J.-P., additional, Fegan, S., additional, Fontaine, G., additional, Füßling, M., additional, Funk, S., additional, Gabici, S., additional, Ghafourizadeh, S., additional, Giavitto, G., additional, Glawion, D., additional, Glicenstein, J. F., additional, Goswami, P., additional, Grolleron, G., additional, Haerer, L., additional, Hofmann, W., additional, Holch, T. L., additional, Holler, M., additional, Horns, D., additional, Jamrozy, M., additional, Jankowsky, F., additional, Joshi, V., additional, Jung-Richardt, I., additional, Kasai, E., additional, Katarzyński, K., additional, Khatoon, R., additional, Khélifi, B., additional, Kluźniak, W., additional, Komin, Nu., additional, Kosack, K., additional, Kostunin, D., additional, Lang, R. G., additional, Le Stum, S., additional, Leitl, F., additional, Lemière, A., additional, Lenain, J.-P., additional, Leuschner, F., additional, Luashvili, A., additional, Mackey, J., additional, Marandon, V., additional, Marchegiani, P., additional, Martí-Devesa, G., additional, Marx, R., additional, Mehta, A., additional, Meyer, M., additional, Mitchell, A., additional, Moderski, R., additional, Mohrmann, L., additional, Montanari, A., additional, Moulin, E., additional, de Naurois, M., additional, Niemiec, J., additional, Priyana Noel, A., additional, O’Brien, P., additional, Ohm, S., additional, Olivera-Nieto, L., additional, de Ona Wilhelmi, E., additional, Ostrowski, M., additional, Panny, S., additional, Panter, M., additional, Peron, G., additional, Prokhorov, D. A., additional, Pühlhofer, G., additional, Punch, M., additional, Quirrenbach, A., additional, Reichherzer, P., additional, Reimer, A., additional, Reimer, O., additional, Ren, H., additional, Rieger, F., additional, Rowell, G., additional, Rudak, B., additional, Ricarte, H. Rueda, additional, Ruiz-Velasco, E., additional, Sahakian, V., additional, Salzmann, H., additional, Sanchez, D. A., additional, Santangelo, A., additional, Sasaki, M., additional, Schüssler, F., additional, Schutte, H. M., additional, Schwanke, U., additional, Shapopi, J. N. S., additional, Sol, H., additional, Specovius, A., additional, Spencer, S., additional, Stawarz, Ł., additional, Steenkamp, R., additional, Steinmassl, S., additional, Steppa, C., additional, Sushch, I., additional, Suzuki, H., additional, Takahashi, T., additional, Tanaka, T., additional, Terrier, R., additional, Tsuji, N., additional, van Eldik, C., additional, van Soelen, B., additional, Vecchi, M., additional, Veh, J., additional, Vink, J., additional, Wach, T., additional, Wagner, S. J., additional, Wierzcholska, A., additional, Zacharias, M., additional, Zargaryan, D., additional, Zdziarski, A. A., additional, Zech, A., additional, Zouari, S., additional, Żywucka, N., additional, Buckley, D. A. H., additional, Cooper, J., additional, and Groenewald, D., additional
Published: 2023
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185. Prototype Tests for the CELESTE Solar Array Gamma--Ray Telescope

Author: Giebels, B., Bazer-Bachi, R., Bergeret, H., Cordier, A., Debiais, G., De Naurois, M., Dezalay, J. P., Dumora, D., Eschstruth, P., Espigat, P., Fabre, B., Fleury, P., Ghesquière, C., Herault, N., Malet, I., Merkel, B., Meynadier, C., Palatka, M., Paré, E., Procureur, J., Punch, M., Québert, J., Ragan, K., Rob, L., Schovanek, P., Smith, D. A., and Vrana, J.
Subjects: Astrophysics
Abstract: The CELESTE experiment will be an Atmospheric Cherenkov detector designed to bridge the gap in energy sensitivity between current satellite and ground-based gamma-ray telescopes, 20 to 300 GeV. We present test results made at the former solar power plant, Themis, in the French Pyrenees. The tests confirm the viability of using a central tower heliostat array for Cherenkov wavefront sampling., Comment: LaTeX2e,30 pages including 14 figures, accepted for publication by Nuclear Instruments & Methods Section A
Published: 1998
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186. Sensitivity of the Cherenkov Telescope Array to TeV photon emission from the Large Magellanic Cloud

Author: Acharyya, A, primary, Adam, R, additional, Aguasca-Cabot, A, additional, Agudo, I, additional, Aguirre-Santaella, A, additional, Alfaro, J, additional, Aloisio, R, additional, Alves Batista, R, additional, Amato, E, additional, Angüner, E O, additional, Aramo, C, additional, Arcaro, C, additional, Asano, K, additional, Aschersleben, J, additional, Ashkar, H, additional, Backes, M, additional, Baktash, A, additional, Balazs, C, additional, Balbo, M, additional, Ballet, J, additional, Bamba, A, additional, Baquero Larriva, A, additional, Barbosa Martins, V, additional, Barres de Almeida, U, additional, Barrio, J A, additional, Bastieri, D, additional, Batista, P, additional, Batkovic, I, additional, Baxter, J R, additional, Becerra González, J, additional, Becker Tjus, J, additional, Benbow, W, additional, Bernardini, E, additional, Bernardos Martín, M I, additional, Bernete Medrano, J, additional, Berti, A, additional, Bertucci, B, additional, Beshley, V, additional, Bhattacharjee, P, additional, Bhattacharyya, S, additional, Bigongiari, C, additional, Biland, A, additional, Bissaldi, E, additional, Bocchino, F, additional, Bordas, P, additional, Borkowski, J, additional, Bottacini, E, additional, Böttcher, M, additional, Bradascio, F, additional, Brown, A M, additional, Bulgarelli, A, additional, Burmistrov, L, additional, Caroff, S, additional, Carosi, A, additional, Carquín, E, additional, Casanova, S, additional, Cascone, E, additional, Cassol, F, additional, Cerruti, M, additional, Chadwick, P, additional, Chaty, S, additional, Chen, A, additional, Chiavassa, A, additional, Chytka, L, additional, Conforti, V, additional, Cortina, J, additional, Costa, A, additional, Costantini, H, additional, Cotter, G, additional, Crestan, S, additional, Cristofari, P, additional, D’Ammando, F, additional, Dalchenko, M, additional, Dazzi, F, additional, De Angelis, A, additional, De Caprio, V, additional, de Gouveia Dal Pino, E M, additional, De Martino, D, additional, de Naurois, M, additional, de Souza, V, additional, del Valle, M V, additional, Delgado Giler, A G, additional, Delgado, C, additional, della Volpe, D, additional, Depaoli, D, additional, Di Girolamo, T, additional, Di Piano, A, additional, Di Pierro, F, additional, Di Tria, R, additional, Di Venere, L, additional, Diebold, S, additional, Doro, M, additional, Dumora, D, additional, Dwarkadas, V V, additional, Eckner, C, additional, Egberts, K, additional, Emery, G, additional, Escudero, J, additional, Falceta-Goncalves, D, additional, Fedorova, E, additional, Fegan, S, additional, Feng, Q, additional, Ferenc, D, additional, Ferrand, G, additional, Fiandrini, E, additional, Filipovic, M, additional, Fioretti, V, additional, Foffano, L, additional, Fontaine, G, additional, Fukui, Y, additional, Gaggero, D, additional, Galanti, G, additional, Galaz, G, additional, Gallozzi, S, additional, Gammaldi, V, additional, Garczarczyk, M, additional, Gasbarra, C, additional, Gasparrini, D, additional, Ghalumyan, A, additional, Giarrusso, M, additional, Giavitto, G, additional, Giglietto, N, additional, Giordano, F, additional, Giuliani, A, additional, Glicenstein, J -F, additional, Goldoni, P, additional, Goulart Coelho, J, additional, Granot, J, additional, Green, D, additional, Green, J G, additional, Grondin, M -H, additional, Gueta, O, additional, Hadasch, D, additional, Hamal, P, additional, Hassan, T, additional, Hayashi, K, additional, Heller, M, additional, Hernández Cadena, S, additional, Hiroshima, N, additional, Hnatyk, B, additional, Hnatyk, R, additional, Hofmann, W, additional, Holder, J, additional, Holler, M, additional, Horan, D, additional, Horvath, P, additional, Hrabovsky, M, additional, Hütten, M, additional, Iarlori, M, additional, Inada, T, additional, Incardona, F, additional, Inoue, S, additional, Iocco, F, additional, Jamrozy, M, additional, Jin, W, additional, Jung-Richardt, I, additional, Juryšek, J, additional, Kantzas, D, additional, Karas, V, additional, Katagiri, H, additional, Kerszberg, D, additional, Knödlseder, J, additional, Komin, N, additional, Kornecki, P, additional, Kosack, K, additional, Kowal, G, additional, Kubo, H, additional, Lamastra, A, additional, Lapington, J, additional, Lemoine-Goumard, M, additional, Lenain, J -P, additional, Leone, F, additional, Leto, G, additional, Leuschner, F, additional, Lindfors, E, additional, Lohse, T, additional, Lombardi, S, additional, Longo, F, additional, López-Coto, R, additional, López-Oramas, A, additional, Loporchio, S, additional, Luque-Escamilla, P L, additional, Macias, O, additional, Majumdar, P, additional, Mandat, D, additional, Mangano, S, additional, Manicò, G, additional, Mariotti, M, additional, Marquez, P, additional, Marsella, G, additional, Martí, J, additional, Martin, P, additional, Martínez, M, additional, Mazin, D, additional, Menchiari, S, additional, Meyer, D M -A, additional, Miceli, D, additional, Miceli, M, additional, Michałowski, J, additional, Mitchell, A, additional, Moderski, R, additional, Mohrmann, L, additional, Molero, M, additional, Molina, E, additional, Montaruli, T, additional, Moralejo, A, additional, Morcuende, D, additional, Morselli, A, additional, Moulin, E, additional, Moya, V, additional, Mukherjee, R, additional, Munari, K, additional, Muraczewski, A, additional, Nagataki, S, additional, Nakamori, T, additional, Nayak, A, additional, Niemiec, J, additional, Nievas, M, additional, Nikołajuk, M, additional, Nishijima, K, additional, Noda, K, additional, Nosek, D, additional, Novosyadlyj, B, additional, Nozaki, S, additional, Ohishi, M, additional, Ohm, S, additional, Okumura, A, additional, Olmi, B, additional, Ong, R A, additional, Orienti, M, additional, Orito, R, additional, Orlandini, M, additional, Orlando, E, additional, Orlando, S, additional, Ostrowski, M, additional, Oya, I, additional, Pagliaro, A, additional, Palatka, M, additional, Pantaleo, F R, additional, Paoletti, R, additional, Paredes, J M, additional, Parmiggiani, N, additional, Patricelli, B, additional, Pech, M, additional, Pecimotika, M, additional, Persic, M, additional, Petruk, O, additional, Pierre, E, additional, Pietropaolo, E, additional, Pirola, G, additional, Pohl, M, additional, Prandini, E, additional, Priyadarshi, C, additional, Pühlhofer, G, additional, Pumo, M L, additional, Punch, M, additional, Queiroz, F S, additional, Quirrenbach, A, additional, Rainò, S, additional, Rando, R, additional, Razzaque, S, additional, Reimer, A, additional, Reimer, O, additional, Reposeur, T, additional, Ribó, M, additional, Richtler, T, additional, Rico, J, additional, Rieger, F, additional, Rigoselli, M, additional, Rizi, V, additional, Roache, E, additional, Rodriguez Fernandez, G, additional, Romano, P, additional, Romeo, G, additional, Rosado, J, additional, Rosales de Leon, A, additional, Rudak, B, additional, Rulten, C, additional, Sadeh, I, additional, Saito, T, additional, Sánchez-Conde, M, additional, Sano, H, additional, Santangelo, A, additional, Santos-Lima, R, additional, Sarkar, S, additional, Saturni, F G, additional, Scherer, A, additional, Schovanek, P, additional, Schussler, F, additional, Schwanke, U, additional, Sergijenko, O, additional, Servillat, M, additional, Siejkowski, H, additional, Siqueira, C, additional, Spencer, S, additional, Stamerra, A, additional, Stanič, S, additional, Steppa, C, additional, Stolarczyk, T, additional, Suda, Y, additional, Tavernier, T, additional, Teshima, M, additional, Tibaldo, L, additional, Torres, D F, additional, Tothill, N, additional, Vacula, M, additional, Vallage, B, additional, Vallania, P, additional, van Eldik, C, additional, Vázquez Acosta, M, additional, Vecchi, M, additional, Ventura, S, additional, Vercellone, S, additional, Viana, A, additional, Vigorito, C F, additional, Vink, J, additional, Vitale, V, additional, Vodeb, V, additional, Vorobiov, S, additional, Vuillaume, T, additional, Wagner, S J, additional, Walter, R, additional, White, M, additional, Wierzcholska, A, additional, Will, M, additional, Yamazaki, R, additional, Yang, L, additional, Yoshikoshi, T, additional, Zacharias, M, additional, Zaharijas, G, additional, Zavrtanik, D, additional, Zavrtanik, M, additional, Zdziarski, A A, additional, Zhdanov, V I, additional, Ziętara, K, additional, and Živec, M, additional
Published: 2023
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187. Search for the evaporation of primordial black holes with H.E.S.S.

Author: Aharonian, F., primary, Ait Benkhali, F., additional, Aschersleben, J., additional, Böttcher, M., additional, Backes, M., additional, Barbosa Martins, V., additional, Batzofin, R., additional, Becherini, Y., additional, Berge, D., additional, Bi, B., additional, Boisson, C., additional, Bolmont, J., additional, de Bony de Lavergne, M., additional, Borowska, J., additional, Bradascio, F., additional, Brose, R., additional, Brun, F., additional, Bruno, B., additional, Bulik, T., additional, Burger-Scheidlin, C., additional, Caroff, S., additional, Casanova, S., additional, Celic, J., additional, Cerruti, M., additional, Chand, T., additional, Chen, A., additional, Chibueze, O., additional, Cotter, G., additional, Damascene Mbarubucyeye, J., additional, Djannati-Ataï, A., additional, Egberts, K., additional, van Eldik, C., additional, Ernenwein, J.-P., additional, Füßling, M., additional, Fiasson, A., additional, Fichet de Clairfontaine, G., additional, Fontaine, G., additional, Gabici, S., additional, Ghafourizadeh, S., additional, Giavitto, G., additional, Glawion, D., additional, Glicenstein, J.F., additional, Grolleron, G., additional, Grondin, M.-H., additional, Haerer, L., additional, Haupt, M., additional, Hinton, J.A., additional, Hofmann, W., additional, Holler, M., additional, Horns, D., additional, Huang, Z.-Q., additional, Jamrozy, M., additional, Jankowsky, F., additional, Joshi, V., additional, Jung-Richardt, I., additional, Kasai, E., additional, Katarzyński, K., additional, Khélifi, B., additional, Klepser, S., additional, Kluźniak, W., additional, Komin, N., additional, Kosack, K., additional, Kostunin, D., additional, Holch, T.L., additional, Lang, R.G., additional, Le Stum, S., additional, Leitl, F., additional, Lemière, A., additional, Lenain, J.-P., additional, Leuschner, F., additional, Lohse, T., additional, Luashvili, A., additional, Lypova, I., additional, Mackey, J., additional, Malyshev, D., additional, Marandon, V., additional, Marchegiani, P., additional, Marinos, P., additional, Martí-Devesa, G., additional, Marx, R., additional, Mitchell, A., additional, Moderski, R., additional, Mohrmann, L., additional, Montanari, A., additional, Moulin, E., additional, Muller, J., additional, Nakashima, K., additional, de Naurois, M., additional, Niemiec, J., additional, O'Brien, P., additional, Ohm, S., additional, Olivera-Nieto, L., additional, de Ona Wilhelmi, E., additional, Ostrowski, M., additional, Pühlhofer, G., additional, Panny, S., additional, Panter, M., additional, Parsons, R.D., additional, Peron, G., additional, Priyana Noel, A., additional, Prokhorov, D.A., additional, Prokoph, H., additional, Punch, M., additional, Quirrenbach, A., additional, Reichherzer, P., additional, Reimer, O., additional, Rieger, F., additional, Rowell, G., additional, Rudak, B., additional, Rueda Ricarte, H., additional, Sahakian, V., additional, Salzmann, H., additional, Sanchez, D.A., additional, Santangelo, A., additional, Sasaki, M., additional, Schutte, H.M., additional, Schwanke, U., additional, Shapopi, J.N.S., additional, Sol, H., additional, Specovius, A., additional, Spencer, S., additional, Stawarz, Ł., additional, Steenkamp, R., additional, Steinmassl, S., additional, Steppa, C., additional, Sushch, I., additional, Suzuki, H., additional, Takahashi, T., additional, Tanaka, T., additional, Tavernier, T., additional, Thorpe-Morgan, C., additional, Tsuji, N., additional, Uchiyama, Y., additional, Vecchi, M., additional, Veh, J., additional, Venter, C., additional, Vink, J., additional, Wagner, S.J., additional, White, R., additional, Wierzcholska, A., additional, Wong, Y.W., additional, Zacharias, M., additional, Zargaryan, D., additional, Zdziarski, A.A., additional, Zech, A., additional, Zouari, S., additional, and Żywucka, N., additional
Published: 2023
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188. H.E.S.S. Follow-up Observations of GRB 221009A

Author: Aharonian, F., primary, Benkhali, F. Ait, additional, Aschersleben, J., additional, Ashkar, H., additional, Backes, M., additional, Baktash, A., additional, Martins, V. Barbosa, additional, Batzofin, R., additional, Becherini, Y., additional, Berge, D., additional, Bernlöhr, K., additional, Bi, B., additional, Böttcher, M., additional, Boisson, C., additional, Bolmont, J., additional, de Bony de Lavergne, M., additional, Borowska, J., additional, Bouyahiaoui, M., additional, Bradascio, F., additional, Breuhaus, M., additional, Brose, R., additional, Brun, F., additional, Bruno, B., additional, Bulik, T., additional, Burger-Scheidlin, C., additional, Caroff, S., additional, Casanova, S., additional, Celic, J., additional, Cerruti, M., additional, Chand, T., additional, Chandra, S., additional, Chen, A., additional, Chibueze, J., additional, Chibueze, O., additional, Cotter, G., additional, Dai, S., additional, Mbarubucyeye, J. Damascene, additional, Devin, J., additional, Djannati-Ataï, A., additional, Dmytriiev, A., additional, Doroshenko, V., additional, Egberts, K., additional, Einecke, S., additional, Ernenwein, J.-P., additional, Fegan, S., additional, de Clairfontaine, G. Fichet, additional, Filipovic, M., additional, Fontaine, G., additional, Füßling, M., additional, Funk, S., additional, Gabici, S., additional, Ghafourizadeh, S., additional, Giavitto, G., additional, Glawion, D., additional, Glicenstein, J. F., additional, Goswami, P., additional, Grolleron, G., additional, Grondin, M.-H., additional, Hinton, J. A., additional, Holch, T. L., additional, Holler, M., additional, Horns, D., additional, Huang, Zhiqiu, additional, Jamrozy, M., additional, Jankowsky, F., additional, Joshi, V., additional, Jung-Richardt, I., additional, Kasai, E., additional, Katarzyński, K., additional, Khatoon, R., additional, Khélifi, B., additional, Kluźniak, W., additional, Komin, Nu., additional, Konno, R., additional, Kosack, K., additional, Kostunin, D., additional, Lang, R. G., additional, Le Stum, S., additional, Leitl, F., additional, Lemière, A., additional, Lemoine-Goumard, M., additional, Lenain, J.-P., additional, Leuschner, F., additional, Lohse, T., additional, Lypova, I., additional, Mackey, J., additional, Malyshev, D., additional, Marandon, V., additional, Marchegiani, P., additional, Marcowith, A., additional, Martí-Devesa, G., additional, Marx, R., additional, Meyer, M., additional, Mitchell, A., additional, Mohrmann, L., additional, Montanari, A., additional, Moulin, E., additional, Murach, T., additional, Nakashima, K., additional, de Naurois, M., additional, Niemiec, J., additional, Noel, A. Priyana, additional, O’Brien, P., additional, Ohm, S., additional, Olivera-Nieto, L., additional, de Ona Wilhelmi, E., additional, Ostrowski, M., additional, Panny, S., additional, Panter, M., additional, Parsons, R. D., additional, Peron, G., additional, Prokhorov, D. A., additional, Prokoph, H., additional, Pühlhofer, G., additional, Punch, M., additional, Quirrenbach, A., additional, Reichherzer, P., additional, Reimer, A., additional, Reimer, O., additional, Ren, H., additional, Renaud, M., additional, Reville, B., additional, Rieger, F., additional, Rowell, G., additional, Rudak, B., additional, Ruiz-Velasco, E., additional, Sahakian, V., additional, Salzmann, H., additional, Santangelo, A., additional, Sasaki, M., additional, Schäfer, J., additional, Schüssler, F., additional, Schutte, H. M., additional, Schwanke, U., additional, Shapopi, J. N. S., additional, Specovius, A., additional, Spencer, S., additional, Stawarz, Ł., additional, Steenkamp, R., additional, Steinmassl, S., additional, Steppa, C., additional, Sushch, I., additional, Suzuki, H., additional, Takahashi, T., additional, Tanaka, T., additional, Terrier, R., additional, Tsuji, N., additional, Uchiyama, Y., additional, Vecchi, M., additional, Venter, C., additional, Vink, J., additional, Wagner, S. J., additional, White, R., additional, Wierzcholska, A., additional, Wong, Yu Wun, additional, Zacharias, M., additional, Zargaryan, D., additional, Zdziarski, A. A., additional, Zech, A., additional, Zhu, S. J., additional, and Żywucka, N., additional
Published: 2023
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189. Detection of extended gamma-ray emission around the Geminga pulsar with HESS

Author: Aharonian, F., Benkhali, F. Ait, Aschersleben, J., Ashkar, H., Backes, M., Martins, V. Barbosa, Batzofin, R., Becherini, Yvonne, Berge, D., Bernloehr, K., Bi, B., Bottcher, M., Boisson, C., Bolmont, J., Borowska, J., Bouyahiaoui, M., Bradascio, F., Brose, R., Brun, F., Bruno, B., Bulik, T., Burger-Scheidlin, C., Cangemi, F., Caroff, S., Casanova, S., Celic, J., Cerruti, M., Chambery, P., Chand, T., Chandra, S., Chen, A., Chibueze, J., Chibueze, O., Cotter, G., Mbarubucyeye, J. Damascene, Devin, J., Djannati-Atai, A., Dmytriiev, A., Egberts, K., Einecke, S., Ernenwein, J. -P, Feijen, K., de Clairfontaine, G. Fichet, Filipovic, M., Fontaine, G., Fuessling, M., Funk, S., Gabici, S., Gallant, Y. A., Ghafourizadeh, S., Giavitto, G., Giunti, L., Glawion, D., Glicenstein, J. F., Goswami, P., Grolleron, G., Grondin, M. -H, Haerer, L., Haupt, M., Hermann, G., Hinton, J. A., Hofmann, W., Holch, T. L., Holler, M., Horns, D., Huang, Zhiqiu, Jamrozy, M., Jankowsky, F., Joshi, V., Jung-Richardt, I., Kasai, E., Katarzynski, K., Khelifi, B., Kluzniak, W., Komin, Nu., Kosack, K., Kostunin, D., Lang, R. G., Le Stum, S., Leitl, F., Lemiere, A., Lemoine-Goumard, M., Lenain, J. -P, Leuschner, F., Lohse, T., Luashvili, A., Lypova, I., Mackey, J., Malyshev, D., Marandon, V., Marchegiani, P., Marcowith, A., Marinos, P., Marti-Devesa, G., Marx, R., Maurin, G., Meintjes, P. J., Meyer, M., Mitchell, A., Moderski, R., Mohrmann, L., Montanari, A., Moulin, E., Muller, J., Nakashima, K., de Naurois, M., Niemiec, J., Noel, A. Priyana, O'Brien, P., Ohm, S., Olivera-Nieto, L., Wilhelmi, E. de Ona, Ostrowski, M., Panny, S., Panter, M., Parsons, R. D., Peron, G., Prokhorov, D. A., Puehlhofer, G., Quirrenbach, A., Reimer, A., Reimer, O., Renaud, M., Reville, B., Rieger, F., Rowell, G., Rudak, B., Ricarte, H. Rueda, Ruiz-Velasco, E., Sahakian, V., Salzmann, H., Santangelo, A., Sasaki, M., Schussler, F., Schutte, H. M., Schwanke, U., Shapopi, J. N. S., Sinha, A., Sol, H., Specovius, A., Spencer, S., Stawarz, L., Steinmassl, S., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Tavernier, T., Taylor, A. M., Terrier, R., Thorpe-Morgan, C., Tsirou, M., Tsuji, N., Vecchi, M., Venter, C., Vink, J., Wagner, S. J., White, R., Wierzcholska, A., Wong, Yu Wun, Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zech, A., Zouari, S., Zywucka, N., Aharonian, F., Benkhali, F. Ait, Aschersleben, J., Ashkar, H., Backes, M., Martins, V. Barbosa, Batzofin, R., Becherini, Yvonne, Berge, D., Bernloehr, K., Bi, B., Bottcher, M., Boisson, C., Bolmont, J., Borowska, J., Bouyahiaoui, M., Bradascio, F., Brose, R., Brun, F., Bruno, B., Bulik, T., Burger-Scheidlin, C., Cangemi, F., Caroff, S., Casanova, S., Celic, J., Cerruti, M., Chambery, P., Chand, T., Chandra, S., Chen, A., Chibueze, J., Chibueze, O., Cotter, G., Mbarubucyeye, J. Damascene, Devin, J., Djannati-Atai, A., Dmytriiev, A., Egberts, K., Einecke, S., Ernenwein, J. -P, Feijen, K., de Clairfontaine, G. Fichet, Filipovic, M., Fontaine, G., Fuessling, M., Funk, S., Gabici, S., Gallant, Y. A., Ghafourizadeh, S., Giavitto, G., Giunti, L., Glawion, D., Glicenstein, J. F., Goswami, P., Grolleron, G., Grondin, M. -H, Haerer, L., Haupt, M., Hermann, G., Hinton, J. A., Hofmann, W., Holch, T. L., Holler, M., Horns, D., Huang, Zhiqiu, Jamrozy, M., Jankowsky, F., Joshi, V., Jung-Richardt, I., Kasai, E., Katarzynski, K., Khelifi, B., Kluzniak, W., Komin, Nu., Kosack, K., Kostunin, D., Lang, R. G., Le Stum, S., Leitl, F., Lemiere, A., Lemoine-Goumard, M., Lenain, J. -P, Leuschner, F., Lohse, T., Luashvili, A., Lypova, I., Mackey, J., Malyshev, D., Marandon, V., Marchegiani, P., Marcowith, A., Marinos, P., Marti-Devesa, G., Marx, R., Maurin, G., Meintjes, P. J., Meyer, M., Mitchell, A., Moderski, R., Mohrmann, L., Montanari, A., Moulin, E., Muller, J., Nakashima, K., de Naurois, M., Niemiec, J., Noel, A. Priyana, O'Brien, P., Ohm, S., Olivera-Nieto, L., Wilhelmi, E. de Ona, Ostrowski, M., Panny, S., Panter, M., Parsons, R. D., Peron, G., Prokhorov, D. A., Puehlhofer, G., Quirrenbach, A., Reimer, A., Reimer, O., Renaud, M., Reville, B., Rieger, F., Rowell, G., Rudak, B., Ricarte, H. Rueda, Ruiz-Velasco, E., Sahakian, V., Salzmann, H., Santangelo, A., Sasaki, M., Schussler, F., Schutte, H. M., Schwanke, U., Shapopi, J. N. S., Sinha, A., Sol, H., Specovius, A., Spencer, S., Stawarz, L., Steinmassl, S., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Tavernier, T., Taylor, A. M., Terrier, R., Thorpe-Morgan, C., Tsirou, M., Tsuji, N., Vecchi, M., Venter, C., Vink, J., Wagner, S. J., White, R., Wierzcholska, A., Wong, Yu Wun, Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zech, A., Zouari, S., and Zywucka, N.
Abstract: Geminga is an enigmatic radio-quiet gamma-ray pulsar located at a mere 250 pc distance from Earth. Extended very-high-energy gamma-ray emission around the pulsar was discovered by Milagro and later confirmed by HAWC, which are both water Cherenkov detector-based experiments. However, evidence for the Geminga pulsar wind nebula in gamma rays has long evaded detection by imaging atmospheric Cherenkov telescopes (IACTs) despite targeted observations. The detection of gamma-ray emission on angular scales greater than or similar to 2 degrees poses a considerable challenge for the background estimation in IACT data analysis. With recent developments in understanding the complementary background estimation techniques of water Cherenkov and atmospheric Cherenkov instruments, the H.E.S.S. IACT array can now confirm the detection of highly extended gamma-ray emission around the Geminga pulsar with a radius of at least 3 degrees in the energy range 0.5-40 TeV. We find no indications for statistically significant asymmetries or energy-dependent morphology. A flux normalisation of (2.8 +/- 0.7) x 10-12 cm-2 s-1 TeV-1 at 1 TeV is obtained within a 1 degrees radius region around the pulsar. To investigate the particle transport within the halo of energetic leptons around the pulsar, we fitted an electron diffusion model to the data. The normalisation of the diffusion coefficient obtained of D-0 = 7.6-1.2+1.5 x 1027 cm2 s-1, at an electron energy of 100 TeV, is compatible with values previously reported for the pulsar halo around Geminga, which is considerably below the Galactic average.
Published: 2023
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190. HESS Follow-up Observations of GRB 221009A

Author: Aharonian, F., Benkhali, F. Ait, Aschersleben, J., Ashkar., H., Backes., M., Baktash, A., Martins, V. Barbosa, Batzofin, R., Becherini, Yvonne, Berge, D., Bernloehr, K., Bi, B., Boettcher, M., Boisson, C., Bolmont, J., de Bony de Lavergne, M., Borowska, J., Bouyahiaoui, M., Bradascio, F., Breuhaus, M., Brose, R., Brun, F., Bruno, B., Bulik, T., Burger-Scheidlin, C., Caroff, S., Casanova, S., Celic, J., Cerruti, M., Chand, T., Chandra, S., Chen, A., Chibueze, J., Chibueze, O., Cotter, G., Dai, S., Mbarubucyeye, J. Damascene, Devin, J., Djannati-Atai, A., Dmytriiev, A., Doroshenko, V., Egberts, K., Einecke, S., Ernenwein, J. -P, Fegan, S., de Clairfontaine, G. Fichet, Filipovic, M., Fontaine, G., Fuessling, M., Funk, S., Gabici, S., Ghafourizadeh, S., Giavitto, G., Glawion, D., Glicenstein, J. F., Goswami, P., Grolleron, G., Grondin, M. -H, Hinton, J. A., Holch, T. L., Holler, M., Horns, D., Huang, Zhiqiu, Jamrozy, M., Jankowsky, F., Joshi, V., Jung-Richardt, I., Kasai, E., Katarzynski, K., Khatoon, R., Khelifi, B., Kluzniak, W., Komin, Nu., Konno, R., Kosack, K., Kostunin, D., Lang, R. G., Le Stum, S., Leitl, F., Lemiere, A., Lemoine-Goumard, M., Lenain, J. -P, Leuschner, F., Lohse, T., Lypova, I., Mackey, J., Malyshev, D., Marandon, V., Marchegiani, P., Marcowith, A., Marti-Devesa, G., Marx, R., Meyer, M., Mitchell, A., Mohrmann, L., Montanari, A., Moulin, E., Murach, T., Nakashima, K., de Naurois, M., Niemiec, J., Noel, A. Priyana, O'Brien, P., Ohm, S., Olivera-Nieto, L., de Ona Wilhelmi, E., Ostrowski, M., Panny, S., Panter, M., Parsons, R. D., Peron, G., Prokhorov, D. A., Prokoph, H., Puehlhofer, G., Punch, M., Quirrenbach, A., Reichherzer, P., Reimer, A., Reimer, O., Ren, H., Renaud, M., Reville, B., Rieger, F., Rowell, G., Rudak, B., Ruiz-Velasco, E., Sahakian, V., Salzmann, H., Santangelo, A., Sasaki, M., Schaefer, J., Schuessler, F., Schutte, H. M., Schwanke, U., Shapopi, J. N. S., Specovius, A., Spencer, S., Stawarz, L., Steenkamp, R., Steinmassl, S., Steppa, C., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Terrier, R., Tsuji, N., Uchiyama, Y., Vecchi, M., Venter, C., Vink, J., Wagner, S. J., White, R., Wierzcholska, A., Wong, Yu Wun, Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zech, A., Zhu, S. J., Zywucka, N., Aharonian, F., Benkhali, F. Ait, Aschersleben, J., Ashkar., H., Backes., M., Baktash, A., Martins, V. Barbosa, Batzofin, R., Becherini, Yvonne, Berge, D., Bernloehr, K., Bi, B., Boettcher, M., Boisson, C., Bolmont, J., de Bony de Lavergne, M., Borowska, J., Bouyahiaoui, M., Bradascio, F., Breuhaus, M., Brose, R., Brun, F., Bruno, B., Bulik, T., Burger-Scheidlin, C., Caroff, S., Casanova, S., Celic, J., Cerruti, M., Chand, T., Chandra, S., Chen, A., Chibueze, J., Chibueze, O., Cotter, G., Dai, S., Mbarubucyeye, J. Damascene, Devin, J., Djannati-Atai, A., Dmytriiev, A., Doroshenko, V., Egberts, K., Einecke, S., Ernenwein, J. -P, Fegan, S., de Clairfontaine, G. Fichet, Filipovic, M., Fontaine, G., Fuessling, M., Funk, S., Gabici, S., Ghafourizadeh, S., Giavitto, G., Glawion, D., Glicenstein, J. F., Goswami, P., Grolleron, G., Grondin, M. -H, Hinton, J. A., Holch, T. L., Holler, M., Horns, D., Huang, Zhiqiu, Jamrozy, M., Jankowsky, F., Joshi, V., Jung-Richardt, I., Kasai, E., Katarzynski, K., Khatoon, R., Khelifi, B., Kluzniak, W., Komin, Nu., Konno, R., Kosack, K., Kostunin, D., Lang, R. G., Le Stum, S., Leitl, F., Lemiere, A., Lemoine-Goumard, M., Lenain, J. -P, Leuschner, F., Lohse, T., Lypova, I., Mackey, J., Malyshev, D., Marandon, V., Marchegiani, P., Marcowith, A., Marti-Devesa, G., Marx, R., Meyer, M., Mitchell, A., Mohrmann, L., Montanari, A., Moulin, E., Murach, T., Nakashima, K., de Naurois, M., Niemiec, J., Noel, A. Priyana, O'Brien, P., Ohm, S., Olivera-Nieto, L., de Ona Wilhelmi, E., Ostrowski, M., Panny, S., Panter, M., Parsons, R. D., Peron, G., Prokhorov, D. A., Prokoph, H., Puehlhofer, G., Punch, M., Quirrenbach, A., Reichherzer, P., Reimer, A., Reimer, O., Ren, H., Renaud, M., Reville, B., Rieger, F., Rowell, G., Rudak, B., Ruiz-Velasco, E., Sahakian, V., Salzmann, H., Santangelo, A., Sasaki, M., Schaefer, J., Schuessler, F., Schutte, H. M., Schwanke, U., Shapopi, J. N. S., Specovius, A., Spencer, S., Stawarz, L., Steenkamp, R., Steinmassl, S., Steppa, C., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Terrier, R., Tsuji, N., Uchiyama, Y., Vecchi, M., Venter, C., Vink, J., Wagner, S. J., White, R., Wierzcholska, A., Wong, Yu Wun, Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zech, A., Zhu, S. J., and Zywucka, N.
Abstract: GRB 221009A is the brightest gamma-ray burst (GRB) ever detected. To probe the very-high-energy (VHE; >100 GeV) emission, the High Energy Stereoscopic System (H.E.S.S.) began observations 53 hr after the triggering event, when the brightness of the moonlight no longer precluded observations. We derive differential and integral upper limits using H.E.S.S. data from the third, fourth, and ninth nights after the initial GRB detection, after applying atmospheric corrections. The combined observations yield an integral energy flux upper limit of f(UL)(95%)=9.7x10(-12)ergcm(-2)s(-1) E-thr = 650 GeV. The constraints derived from the H.E.S.S. observations complement the available multiwavelength data. The radio to X-ray data are consistent with synchrotron emission from a single electron population, with the peak in the spectral energy distribution occurring above the X-ray band. Compared to the VHE-bright GRB 190829A, the upper limits for GRB 221009A imply a smaller gamma-ray to X-ray flux ratio in the afterglow. Even in the absence of a detection, the H.E.S.S. upper limits thus contribute to the multiwavelength picture of GRB 221009A, effectively ruling out an IC-dominated scenario.
Published: 2023
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191. HESS J1809-193 : A halo of escaped electrons around a pulsar wind nebula?

Author: Aharonian, F., Ait Benkhali, F., Aschersleben, J., Ashkar, H., Backes, M., Barbosa Martins, V., Batzofin, R., Becherini, Yvonne, Berge, D., Boettcher, M., Boisson, C., Bolmont, J., Borowska, J., Bouyahiaoui, M., Bradascio, F., Breuhaus, M., Brose, R., Brun, F., Bruno, B., Bulik, T., Burger-Scheidlin, C., Bylund, Tomas, Caroff, S., Casanova, S., Celic, J., Cerruti, M., Chambery, P., Chand, T., Chen, A., Chibueze, J., Chibueze, O., Damascene Mbarubucyeye, J., Djannati-Atai, A., Dmytriiev, A., Einecke, S., Ernenwein, J. -p., Feijen, K., Filipovic, M., Fontaine, G., Fuessling, M., Funk, S., Gabici, S., Gallant, Y. A., Ghafourizadeh, S., Giavitto, G., Giunti, L., Glawion, D., Goswami, P., Grolleron, G., Grondin, M. -h., Haerer, L., Hinton, J. A., Hofmann, W., Holch, T. L., Holler, M., Horns, D., Huang, Zhiqiu, Jamrozy, M., Jankowsky, F., Joshi, V., Jung-Richardt, I., Kasai, E., Katarzynski, K., Khelifi, B., Kluzniak, W., Komin, Nu., Kosack, K., Kostunin, D., Lang, R. G., Le Stum, S., Leitl, F., Lemiere, A., Lemoine-Goumard, M., Lenain, J. -p., Leuschner, F., Lohse, T., Luashvili, A., Lypova, I., Mackey, J., Malyshev, D., Marandon, V., Marchegiani, P., Marcowith, A., Marinos, P., Marti-Devesa, G., Marx, R., Mitchell, A., Moderski, R., Mohrmann, L., Montanari, A., Moulin, E., Muller, J., Nakashima, K., de Naurois, M., Niemiec, J., Priyana Noel, A., Ohm, S., Olivera-Nieto, L., de Ona Wilhelmi, E., Ostrowski, M., Panny, S., Panter, M., Parsons, R. D., Prokhorov, D. A., Puehlhofer, G., Punch, M., Quirrenbach, A., Reichherzer, P., Reimer, A., Reimer, O., Renaud, M., Reville, B., Rieger, F., Rowell, G., Rudak, B., Sahakian, V., Santangelo, A., Sasaki, M., Schutte, H. M., Schwanke, U., Shapopi, J. N. S., Sol, H., Specovius, A., Spencer, S., Stawarz, L., Steenkamp, R., Steinmassl, S., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Terrier, R., Thorpe-Morgan, C., Tsirou, M., Tsuji, N., Uchiyama, Y., van Eldik, C., Vecchi, M., Veh, J., Venter, C., Vink, J., Wach, T., Wagner, S. J., White, R., Wierzcholska, A., Wong, Yu Wun, Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zech, A., Zouari, S., Zywucka, N., Aharonian, F., Ait Benkhali, F., Aschersleben, J., Ashkar, H., Backes, M., Barbosa Martins, V., Batzofin, R., Becherini, Yvonne, Berge, D., Boettcher, M., Boisson, C., Bolmont, J., Borowska, J., Bouyahiaoui, M., Bradascio, F., Breuhaus, M., Brose, R., Brun, F., Bruno, B., Bulik, T., Burger-Scheidlin, C., Bylund, Tomas, Caroff, S., Casanova, S., Celic, J., Cerruti, M., Chambery, P., Chand, T., Chen, A., Chibueze, J., Chibueze, O., Damascene Mbarubucyeye, J., Djannati-Atai, A., Dmytriiev, A., Einecke, S., Ernenwein, J. -p., Feijen, K., Filipovic, M., Fontaine, G., Fuessling, M., Funk, S., Gabici, S., Gallant, Y. A., Ghafourizadeh, S., Giavitto, G., Giunti, L., Glawion, D., Goswami, P., Grolleron, G., Grondin, M. -h., Haerer, L., Hinton, J. A., Hofmann, W., Holch, T. L., Holler, M., Horns, D., Huang, Zhiqiu, Jamrozy, M., Jankowsky, F., Joshi, V., Jung-Richardt, I., Kasai, E., Katarzynski, K., Khelifi, B., Kluzniak, W., Komin, Nu., Kosack, K., Kostunin, D., Lang, R. G., Le Stum, S., Leitl, F., Lemiere, A., Lemoine-Goumard, M., Lenain, J. -p., Leuschner, F., Lohse, T., Luashvili, A., Lypova, I., Mackey, J., Malyshev, D., Marandon, V., Marchegiani, P., Marcowith, A., Marinos, P., Marti-Devesa, G., Marx, R., Mitchell, A., Moderski, R., Mohrmann, L., Montanari, A., Moulin, E., Muller, J., Nakashima, K., de Naurois, M., Niemiec, J., Priyana Noel, A., Ohm, S., Olivera-Nieto, L., de Ona Wilhelmi, E., Ostrowski, M., Panny, S., Panter, M., Parsons, R. D., Prokhorov, D. A., Puehlhofer, G., Punch, M., Quirrenbach, A., Reichherzer, P., Reimer, A., Reimer, O., Renaud, M., Reville, B., Rieger, F., Rowell, G., Rudak, B., Sahakian, V., Santangelo, A., Sasaki, M., Schutte, H. M., Schwanke, U., Shapopi, J. N. S., Sol, H., Specovius, A., Spencer, S., Stawarz, L., Steenkamp, R., Steinmassl, S., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Terrier, R., Thorpe-Morgan, C., Tsirou, M., Tsuji, N., Uchiyama, Y., van Eldik, C., Vecchi, M., Veh, J., Venter, C., Vink, J., Wach, T., Wagner, S. J., White, R., Wierzcholska, A., Wong, Yu Wun, Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zech, A., Zouari, S., and Zywucka, N.
Abstract: Context. HESS J1809-193 is an unassociated very-high-energy gamma-ray source located on the Galactic plane. While it has been connected to the nebula of the energetic pulsar PSR J1809-1917, supernova remnants and molecular clouds present in the vicinity also constitute possible associations. Recently, the detection of gamma-ray emission up to energies of similar to 100 TeV with the HAWC observatory has led to renewed interest in HESS J1809-193.Aims. We aim to understand the origin of the gamma-ray emission of HESS J1809-193.Methods. We analysed 93.2 h of data taken on HESS J1809-193 above 0.27 TeV with the High Energy Stereoscopic System (H.E.S.S.), using a multi-component, three-dimensional likelihood analysis. In addition, we provide a new analysis of 12.5 yr of Fermi-LAT data above 1 GeV within the region of HESS J1809-193. The obtained results are interpreted in a time-dependent modelling framework.Results. For the first time, we were able to resolve the emission detected with H.E.S.S. into two components: an extended component (modelled as an elongated Gaussian with a 1-sigma semi-major and semi-minor axis of similar to 0.62 degrees and similar to 0.35 degrees, respectively) that exhibits a spectral cutoff at similar to 13 TeV, and a compact component (modelled as a symmetric Gaussian with a 1-sigma radius of similar to 0.1 degrees) that is located close to PSR J1809-1917 and shows no clear spectral cutoff. The Fermi-LAT analysis also revealed extended gamma-ray emission, on scales similar to that of the extended H.E.S.S. component.Conclusions. Our modelling indicates that based on its spectrum and spatial extent, the extended H.E.S.S. component is likely caused by inverse Compton emission from old electrons that form a halo around the pulsar wind nebula. The compact component could be connected to either the pulsar wind nebula or the supernova remnant and molecular clouds. Due to its comparatively steep spectrum, modelling the Fermi-LAT emission together with
Published: 2023
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192. Search for the evaporation of primordial black holes with HESS

Author: Aharonian, F., Benkhali, F. Ait, Aschersleben, J., Boettcher, M., Backes, M., Martins, V. Barbosa, Batzofin, R., Becherini, Yvonne, Berge, D., Bi, B., Boisson, C., Bolmont, J., de Lavergne, M. de Bony, Borowska, J., Bradascio, F., Brose, R., Brun, F., Bruno, B., Bulik, T., Burger-Scheidlin, C., Caroff, S., Casanova, S., Celic, J., Cerruti, M., Chand, T., Chen, A., Chibueze, O., Cotter, G., Mbarubucyeye, J. Damascene, Djannati-Atai, A., Egberts, K., van Eldik, C., Ernenwein, J. -P, Fuessling, M., Fiasson, A., de Clairfontaine, G. Fichet, Fontaine, G., Gabici, S., Ghafourizadeh, S., Giavitto, G., Glawion, D., Glicenstein, J. F., Grolleron, G., Grondin, M. -H, Haerer, L., Haupt, M., Hinton, J. A., Hofmann, W., Holler, M., Horns, D., Huang, Z. -Q, Jamrozy, M., Jankowsky, F., Joshi, V., Jung-Richardt, I., Kasai, E., Katarzynski, K., Khelifi, B., Klepser, S., Kluzniak, W., Komin, N., Kosack, K., Kostunin, D., Holch, T. L., Lang, R. G., Le Stum, S., Leitl, F., Lemiere, A., Lenain, J. -P, Leuschner, F., Lohse, T., Luashvili, A., Lypova, I., Mackey, J., Malyshev, D., Marandon, V., Marchegiani, P., Marinos, P., Marti-Devesa, G., Marx, R., Mitchell, A., Moderski, R., Mohrmann, L., Montanari, A., Moulin, E., Muller, J., Nakashima, K., de Naurois, M., Niemiec, J., O'Brien, P., Ohm, S., Olivera-Nieto, L., Wilhelmi, E. de Ona, Ostrowski, M., Puehlhofer, G., Panny, S., Panter, M., Parsons, R. D., Peron, G., Noel, A. Priyana, Prokhorov, D. A., Prokoph, H., Punch, Michael, Quirrenbach, A., Reichherzer, P., Reimer, O., Rieger, F., Rowell, G., Rudak, B., Ricarte, H. Rueda, Sahakian, V., Salzmann, H., Sanchez, D. A., Santangelo, A., Sasaki, M., Schutte, H. M., Schwanke, U., Shapopi, J. N. S., Sol, H., Specovius, A., Spencer, S., Stawarz, L., Steenkamp, R., Steinmassl, S., Steppa, C., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Tavernier, T., Thorpe-Morgan, C., Tsuji, N., Uchiyama, Y., Vecchi, M., Veh, J., Venter, C., Vink, J., Wagner, S. J., White, R., Wierzcholska, A., Wong, Y. W., Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zech, A., Zouari, S., Zywucka, N., Aharonian, F., Benkhali, F. Ait, Aschersleben, J., Boettcher, M., Backes, M., Martins, V. Barbosa, Batzofin, R., Becherini, Yvonne, Berge, D., Bi, B., Boisson, C., Bolmont, J., de Lavergne, M. de Bony, Borowska, J., Bradascio, F., Brose, R., Brun, F., Bruno, B., Bulik, T., Burger-Scheidlin, C., Caroff, S., Casanova, S., Celic, J., Cerruti, M., Chand, T., Chen, A., Chibueze, O., Cotter, G., Mbarubucyeye, J. Damascene, Djannati-Atai, A., Egberts, K., van Eldik, C., Ernenwein, J. -P, Fuessling, M., Fiasson, A., de Clairfontaine, G. Fichet, Fontaine, G., Gabici, S., Ghafourizadeh, S., Giavitto, G., Glawion, D., Glicenstein, J. F., Grolleron, G., Grondin, M. -H, Haerer, L., Haupt, M., Hinton, J. A., Hofmann, W., Holler, M., Horns, D., Huang, Z. -Q, Jamrozy, M., Jankowsky, F., Joshi, V., Jung-Richardt, I., Kasai, E., Katarzynski, K., Khelifi, B., Klepser, S., Kluzniak, W., Komin, N., Kosack, K., Kostunin, D., Holch, T. L., Lang, R. G., Le Stum, S., Leitl, F., Lemiere, A., Lenain, J. -P, Leuschner, F., Lohse, T., Luashvili, A., Lypova, I., Mackey, J., Malyshev, D., Marandon, V., Marchegiani, P., Marinos, P., Marti-Devesa, G., Marx, R., Mitchell, A., Moderski, R., Mohrmann, L., Montanari, A., Moulin, E., Muller, J., Nakashima, K., de Naurois, M., Niemiec, J., O'Brien, P., Ohm, S., Olivera-Nieto, L., Wilhelmi, E. de Ona, Ostrowski, M., Puehlhofer, G., Panny, S., Panter, M., Parsons, R. D., Peron, G., Noel, A. Priyana, Prokhorov, D. A., Prokoph, H., Punch, Michael, Quirrenbach, A., Reichherzer, P., Reimer, O., Rieger, F., Rowell, G., Rudak, B., Ricarte, H. Rueda, Sahakian, V., Salzmann, H., Sanchez, D. A., Santangelo, A., Sasaki, M., Schutte, H. M., Schwanke, U., Shapopi, J. N. S., Sol, H., Specovius, A., Spencer, S., Stawarz, L., Steenkamp, R., Steinmassl, S., Steppa, C., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Tavernier, T., Thorpe-Morgan, C., Tsuji, N., Uchiyama, Y., Vecchi, M., Veh, J., Venter, C., Vink, J., Wagner, S. J., White, R., Wierzcholska, A., Wong, Y. W., Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zech, A., Zouari, S., and Zywucka, N.
Abstract: Primordial Black Holes (PBHs) are hypothetical black holes predicted to have been formed from density fluctuations in the early Universe. PBHs with an initial mass around 1014-1015 g are expected to end their evaporation at present times in a burst of particles and very-high-energy (VHE) gamma rays. Those gamma rays may be detectable by the High Energy Stereoscopic System (H.E.S.S.), an array of imaging atmospheric Cherenkov telescopes. This paper reports on the search for evaporation bursts of VHE gamma rays with H.E.S.S., ranging from 10 to 120 seconds, as expected from the final stage of PBH evaporation and using a total of 4816 hours of observations. The most constraining upper limit on the burst rate of local PBHs is 2000 pc-3 yr-1 for a burst interval of 120 seconds, at the 95% confidence level. The implication of these measurements for PBH dark matter are also discussed.
Published: 2023
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193. Discovery of a radiation component from the Vela pulsar reaching 20 teraelectronvolts

Author: Aharonian, F., Benkhali, F. Ait, Aschersleben, J., Ashkar, H., Backers, M., Martins, V. Barbosa, Batzofin, R., Becherini, Yvonne, Berge, D., Bernlohr, K., Bi, B., Bottcher, M., Boisson, C., Bolmont, J., de Lavergne, M. de Bony, Borowska, J., Bradascio, F., Breuhaus, M., Brose, R., Brun, F., Bruno, B., Bulik, T., Burger-Scheidlin, C., Bylund, Tomas, Cangemi, F., Caroff, S., Casanova, S., Celic, J., Cerruti, M., Chand, T., Chandra, S., Chen, A., Chibueze, O., Cotter, G., Mbarubucyeye, J. Damascene, Djannati-Atai, A., Dmytriiev, A., Egberts, K., Ernenwein, J. -P, Feijen, K., Fiasson, A., de Clairfontaine, G. Fichet, Fontaine, G., Fussling, M., Funk, S., Gabici, S., Gallant, Y. A., Ghafourizadeh, S., Giavitto, G., Giunti, L., Glawion, D., Glicenstein, J. F., Goswami, P., Grolleron, G., Grondin, M. -H, Haerer, L., Haupt, M., Hinton, J. A., Hofmann, W., Holch, T. L., Holler, M., Horns, D., Huang, Z., Jamrozy, M., Jankowsky, F., Joshi, V., Jung-Richardt, I., Kasai, E., Katarzynski, K., Khelifi, B., Klepser, S., Kluzniak, W., Komin, Nu., Kosack, K., Kostunin, D., Lang, R. G., Le Stum, S., Lemiere, A., Lemoine-Goumard, M., Lenain, J. -P, Leuschner, F., Lohse, T., Luashvili, A., Lypova, I., Mackey, J., Malyshev, D., Marandon, V., Marchegiani, P., Marcowith, A., Marinos, P., Marti-Devesa, G., Marx, R., Maurin, G., Meyer, M., Mitchell, A., Moderski, R., Mohrmann, L., Montanari, A., Moulin, E., Muller, J., Murach, T., Nakashima, K., de Naurois, M., Niemiec, J., Noel, A. Priyana, O'Brien, P., Ohm, S., Olivera-Nieto, L., Wilhelmi, E. de Ona, Ostrowski, M., Panny, S., Panter, M., Parsons, R. D., Peron, G., Pita, S., Prokhorov, D. A., Prokoph, H., Puhlhofer, G., Punch, Michael, Quirrenbach, A., Reichherzer, P., Reimer, A., Reimer, O., Renaud, M., Rieger, F., Rowell, G., Rudak, B., Ruiz-Velasco, E., Sahakian, V., Sailer, S., Salzmann, H., Sanchez, D. A., Santangelo, A., Sasaki, M., Schussler, F., Schwanke, U., Shapopi, J. N. S., Sinha, A., Sol, H., Specovius, A., Spencer, S., Spir-Jacob, M., Stawarz, L., Steenkamp, R., Steinmassl, S., Steppa, C., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Tavernier, T., Terrier, R., Thorpe-Morgan, C., Tluczykont, M., Tsirou, M., Tsuji, N., van Eldik, C., Vecchi, M., Veh, J., Venter, C., Vink, J., Wagner, S. J., Werner, F., White, R., Wierzcholska, A., Wong, Y. Wun, Yassin, H., Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zech, A., Zhu, S. J., Zouari, S., Zywucka, N., Zanin, R., Kerr, M., Johnston, S., Shannon, R. M., Smith, D. A., Aharonian, F., Benkhali, F. Ait, Aschersleben, J., Ashkar, H., Backers, M., Martins, V. Barbosa, Batzofin, R., Becherini, Yvonne, Berge, D., Bernlohr, K., Bi, B., Bottcher, M., Boisson, C., Bolmont, J., de Lavergne, M. de Bony, Borowska, J., Bradascio, F., Breuhaus, M., Brose, R., Brun, F., Bruno, B., Bulik, T., Burger-Scheidlin, C., Bylund, Tomas, Cangemi, F., Caroff, S., Casanova, S., Celic, J., Cerruti, M., Chand, T., Chandra, S., Chen, A., Chibueze, O., Cotter, G., Mbarubucyeye, J. Damascene, Djannati-Atai, A., Dmytriiev, A., Egberts, K., Ernenwein, J. -P, Feijen, K., Fiasson, A., de Clairfontaine, G. Fichet, Fontaine, G., Fussling, M., Funk, S., Gabici, S., Gallant, Y. A., Ghafourizadeh, S., Giavitto, G., Giunti, L., Glawion, D., Glicenstein, J. F., Goswami, P., Grolleron, G., Grondin, M. -H, Haerer, L., Haupt, M., Hinton, J. A., Hofmann, W., Holch, T. L., Holler, M., Horns, D., Huang, Z., Jamrozy, M., Jankowsky, F., Joshi, V., Jung-Richardt, I., Kasai, E., Katarzynski, K., Khelifi, B., Klepser, S., Kluzniak, W., Komin, Nu., Kosack, K., Kostunin, D., Lang, R. G., Le Stum, S., Lemiere, A., Lemoine-Goumard, M., Lenain, J. -P, Leuschner, F., Lohse, T., Luashvili, A., Lypova, I., Mackey, J., Malyshev, D., Marandon, V., Marchegiani, P., Marcowith, A., Marinos, P., Marti-Devesa, G., Marx, R., Maurin, G., Meyer, M., Mitchell, A., Moderski, R., Mohrmann, L., Montanari, A., Moulin, E., Muller, J., Murach, T., Nakashima, K., de Naurois, M., Niemiec, J., Noel, A. Priyana, O'Brien, P., Ohm, S., Olivera-Nieto, L., Wilhelmi, E. de Ona, Ostrowski, M., Panny, S., Panter, M., Parsons, R. D., Peron, G., Pita, S., Prokhorov, D. A., Prokoph, H., Puhlhofer, G., Punch, Michael, Quirrenbach, A., Reichherzer, P., Reimer, A., Reimer, O., Renaud, M., Rieger, F., Rowell, G., Rudak, B., Ruiz-Velasco, E., Sahakian, V., Sailer, S., Salzmann, H., Sanchez, D. A., Santangelo, A., Sasaki, M., Schussler, F., Schwanke, U., Shapopi, J. N. S., Sinha, A., Sol, H., Specovius, A., Spencer, S., Spir-Jacob, M., Stawarz, L., Steenkamp, R., Steinmassl, S., Steppa, C., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Tavernier, T., Terrier, R., Thorpe-Morgan, C., Tluczykont, M., Tsirou, M., Tsuji, N., van Eldik, C., Vecchi, M., Veh, J., Venter, C., Vink, J., Wagner, S. J., Werner, F., White, R., Wierzcholska, A., Wong, Y. Wun, Yassin, H., Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zech, A., Zhu, S. J., Zouari, S., Zywucka, N., Zanin, R., Kerr, M., Johnston, S., Shannon, R. M., and Smith, D. A.
Abstract: Gamma-ray observations have established energetic isolated pulsars as outstanding particle accelerators and antimatter factories. However, many questions are still open regarding the acceleration and radiation processes involved, as well as the locations where they occur. The radiation spectra of all gamma-ray pulsars observed to date show strong cutoffs or a break above energies of a few gigaelectronvolts. Using the High Energy Stereoscopic System's Cherenkov telescopes, we discovered a radiation component from the Vela pulsar which emerges beyond this generic cutoff and extends up to energies of at least 20 teraelectronvolts. This is an order of magnitude larger than in the case of the Crab pulsar, the only other pulsar detected in the teraelectronvolt energy range. Our results challenge the state-of-the-art models for the high-energy emission of pulsars. Furthermore, they pave the way for investigating other pulsars through their multiteraelectronvolt emission, thereby imposing additional constraints on the acceleration and emission processes in their extreme energy limit. The H.E.S.S. gamma-ray observatory has observed gamma rays with energies of at least 20 TeV from a pulsar, an energy regime that is hard to reconcile with the existing theories of gamma-ray production for such objects., Correction published in: https://doi.org/10.1038/s41550-023-02151-1.In the version of the article initially published, R. Zanin, M. Kerr, S. Johnston, R. M. Shannon and D. A. Smith mistakenly appeared in the main author list but are now instead listed as members of The H.E.S.S. Collaboration et al. in the HTML and PDF versions of the article.
Published: 2023
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194. HESS J1809−193 : a halo of escaped electrons around a pulsar wind nebula?

Author: Aharonian, F., Ait Benkhali, F., Aschersleben, J., Ashkar, H., Backes, M., Barbosa Martins, V., Batzofin, R., Becherini, Y., Berge, D., Böttcher, M., Boisson, C., Bolmont, J., Borowska, J., Bouyahiaoui, M., Bradascio, F., Breuhaus, M., Brose, R., Brun, F., Bruno, B., Bulik, T., Burger-Scheidlin, C., Bylund, T., Caroff, S., Casanova, S., Celic, J., Cerruti, M., Chambery, P., Chand, T., Chen, A., Chibueze, J., Chibueze, O., Damascene Mbarubucyeye, J., Djannati-Ataï, A., Dmytriiev, A., Einecke, S., Ernenwein, J. -P., Feijen, K., Filipovic, M., Fontaine, G., Füßling, M., Funk, S., Gabici, S., Gallant, Y. A., Ghafourizadeh, S., Giavitto, G., Giunti, L., Glawion, D., Goswami, P., Grolleron, G., Grondin, M. -H., Haerer, L., Hinton, J. A., Hofmann, W., Holch, T. L., Holler, M., Horns, D., Huang, Zhiqiu, Jamrozy, Marek, Jankowsky, F., Joshi, V., Jung-Richardt, I., Kasai, E., Katarzyński, K., Khélifi, B., Kluźniak, W., Komin, Nu., Kosack, K., Kostunin, D., Lang, R. G., Le Stum, S., Leitl, F., Lemière, A., Lemoine-Goumard, M., Lenain, J. -P., Leuschner, F., Lohse, T., Luashvili, A., Lypova, I., Mackey, J., Malyshev, D., Marandon, V., Marchegiani, P., Marcowith, A., Marinos, P., Martí-Devesa, G., Marx, R., Mitchell, A., Moderski, R., Mohrmann, L., Montanari, A., Moulin, E., Muller, J., Nakashima, K., de Naurois, M., Niemiec, J., Noel, Angel, Ohm, S., Olivera-Nieto, L., de Ona Wilhelmi, E., Ostrowski, Michał, Panny, S., Panter, M., Parsons, R. D., Prokhorov, D. A., Pühlhofer, G., Punch, M., Quirrenbach, A., Reichherzer, P., Reimer, A., Reimer, O., Renaud, M., Reville, B., Rieger, F., Rowell, G., Rudak, B., Sahakian, V., Santangelo, A., Sasaki, M., Schutte, H. M., Schwanke, U., Shapopi, J. N. S., Sol, H., Specovius, A., Spencer, S., Stawarz, Łukasz, Steenkamp, R., Steinmassl, S., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Terrier, R., Thorpe-Morgan, C., Tsirou, M., Tsuji, N., Uchiyama, Y., van Eldik, C., Vecchi, M., Veh, J., Venter, C., Vink, J., Wach, T., Wagner, S. J., White, R., Wierzcholska, Alicja, Wong, Yu Wun, Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zech, A., Zouari, S., and Żywucka, N.
Subjects: non-thermal [radiation mechanisms], general [gamma rays], acceleration of particles, individual: PSR J1809-1917 [pulsars]
Abstract: Context. HESS J1809−193 is an unassociated very-high-energy γ-ray source located on the Galactic plane. While it has been connected to the nebula of the energetic pulsar PSR J1809−1917, supernova remnants and molecular clouds present in the vicinity also constitute possible associations. Recently, the detection of γ-ray emission up to energies of ∼100 TeV with the HAWC observatory has led to renewed interest in HESS J1809−193. Aims. We aim to understand the origin of the γ-ray emission of HESS J1809−193. Methods. We analysed 93.2 h of data taken on HESS J1809−193 above 0.27 TeV with the High Energy Stereoscopic System (H.E.S.S.), using a multi-component, three-dimensional likelihood analysis. In addition, we provide a new analysis of 12.5 yr of Fermi-LAT data above 1 GeV within the region of HESS J1809−193. The obtained results are interpreted in a time-dependent modelling framework. Results. For the first time, we were able to resolve the emission detected with H.E.S.S. into two components: an extended component (modelled as an elongated Gaussian with a 1-σ semi-major and semi-minor axis of ∼0.62° and ∼0.35°, respectively) that exhibits a spectral cutoff at ∼13 TeV, and a compact component (modelled as a symmetric Gaussian with a 1-σ radius of ∼0.1°) that is located close to PSR J1809−1917 and shows no clear spectral cutoff. The Fermi-LAT analysis also revealed extended γ-ray emission, on scales similar to that of the extended H.E.S.S. component. Conclusions. Our modelling indicates that based on its spectrum and spatial extent, the extended H.E.S.S. component is likely caused by inverse Compton emission from old electrons that form a halo around the pulsar wind nebula. The compact component could be connected to either the pulsar wind nebula or the supernova remnant and molecular clouds. Due to its comparatively steep spectrum, modelling the Fermi-LAT emission together with the H.E.S.S. components is not straightforward.
Published: 2023

195. Sensitivity of the Cherenkov Telescope Array to TeV photon emission from the Large Magellanic Cloud

Author: Acharyya, A., Adam, R., Aguasca-Cabot, A., Agudo, I., Aguirre-Santaella, A., Alfaro, J., Aloisio, R., Alves Batista, R., Amato, E., Angüner, E. O., Aramo, C., Arcaro, C., Asano, K., Aschersleben, J., Ashkar, H., Backes, M., Baktash, A., Balazs, C., Balbo, M., Ballet, J., Bamba, A., Larriva, A. Baquero, Barbosa Martins, V., de Almeida, U. Barres, Barrio, J. A., Bastieri, D., Batista, P., Batkovic, I., Baxter, J. R., González, J. Becerra, Becker Tjus, J., Benbow, W., Bernardini, E., Martín, M. I. Bernardos, Medrano, J. Bernete, Berti, A., Bertucci, B., Beshley, V., Bhattacharjee, P., Bhattacharyya, S., Bigongiari, C., Biland, A., Bissaldi, E., Bocchino, F., Bordas, P., Borkowski, J., Bottacini, E., Böttcher, M., Bradascio, F., Brown, A. M., Bulgarelli, A., Burmistrov, L., Caroff, S., Carosi, A., Carquín, E., Casanova, S., Cascone, E., Cassol, F., Cerruti, M., Chadwick, P., Chaty, S., Chen, A., Chiavassa, A., Chytka, L., Conforti, V., Cortina, J., Costa, A., Costantini, H., Cotter, G., Crestan, S., Cristofari, P., D'Ammando, F., Dalchenko, M., Dazzi, F., De Angelis, A., De Caprio, V., de Gouveia Dal Pino, E. M., De Martino, D., de Naurois, M., de Souza, V., del Valle, M. V., Giler, A. G. Delgado, Delgado, C., della Volpe, D., Depaoli, D., Di Girolamo, T., Di Piano, A., Di Pierro, F., Di Tria, R., Di Venere, L., Diebold, S., Doro, M., Dumora, D., Dwarkadas, V. V., Eckner, C., Egberts, K., Emery, G., Escudero, J., Falceta-Goncalves, D., Fedorova, E., Fegan, S., Feng, Q., Ferenc, D., Ferrand, G., Fiandrini, E., Filipovic, M., Fioretti, V., Foffano, L., Fontaine, G., Fukui, Y., Gaggero, D., Galanti, G., Galaz, G., Gallozzi, S., Gammaldi, V., Garczarczyk, M., Gasbarra, C., Gasparrini, D., Ghalumyan, A., Giarrusso, M., Giavitto, G., Giglietto, N., Giordano, F., Giuliani, A., Glicenstein, J.-F., Goldoni, P., Coelho, J. Goulart, Granot, J., Green, D., Green, J. G., Grondin, M.-H., Gueta, O., Hadasch, D., Hamal, P., Hassan, T., Hayashi, K., Heller, M., Cadena, S. Hernández, Hiroshima, N., Hnatyk, B., Hnatyk, R., Hofmann, W., Holder, J., Holler, M., Horan, D., Horvath, P., Hrabovsky, M., Hütten, M., Iarlori, M., Inada, T., Incardona, F., Inoue, S., Iocco, F., Jamrozy, M., Jin, W., Jung-Richardt, I., Juryšek, J., Kantzas, D., Karas, V., Katagiri, H., Kerszberg, D., Knödlseder, J., Komin, N., Kornecki, P., Kosack, K., Kowal, G., Kubo, H., Lamastra, A., Lapington, J., Lemoine-Goumard, M., Lenain, J.-P., Leone, F., Leto, G., Leuschner, F., Lindfors, E., Lohse, T., Lombardi, S., Longo, F., López-Coto, R., López-Oramas, A., Loporchio, S., Luque-Escamilla, P. L., Macias, O., Majumdar, P., Mandat, D., Mangano, S., Manicò, G., Mariotti, M., Marquez, P., Marsella, G., Martí, J., Martin, P., Martínez, M., Mazin, D., Menchiari, S., Meyer, D. M.-A., Miceli, D., Miceli, M., Michałowski, J., Mitchell, A., Moderski, R., Mohrmann, L., Molero, M., Molina, E., Montaruli, T., Moralejo, A., Morcuende, D., Morselli, A., Moulin, E., Moya, V., Mukherjee, R., Munari, K., Muraczewski, A., Nagataki, S., Nakamori, T., Nayak, A., Niemiec, J., Nievas, M., Nikołajuk, M., Nishĳima, K., Noda, K., Nosek, D., Novosyadlyj, B., Nozaki, S., Ohishi, M., Ohm, S., Okumura, A., Olmi, B., Ong, R. A., Orienti, M., Orito, R., Orlandini, M., Orlando, E., Orlando, S., Ostrowski, M., Oya, I., Pagliaro, A., Palatka, M., Pantaleo, F. R., Paoletti, R., Paredes, J. M., Parmiggiani, N., Patricelli, B., Pech, M., Pecimotika, M., Persic, M., Petruk, O., Pierre, E., Pietropaolo, E., Pirola, G., Pohl, M., Prandini, E., Priyadarshi, C., Pühlhofer, G., Pumo, M. L., Punch, M., Queiroz, F. S., Quirrenbach, A., Rainò, S., Rando, R., Razzaque, S., Reimer, A., Reimer, O., Reposeur, T., Ribó, M., Richtler, T., Rico, J., Rieger, F., Rigoselli, M., Rizi, V., Roache, E., Fernandez, G. Rodriguez, Romano, P., Romeo, G., Rosado, J., de Leon, A. Rosales, Rudak, B., Rulten, C., Sadeh, I., Saito, T., Sánchez-Conde, M., Sano, H., Santangelo, A., Santos-Lima, R., Sarkar, S., Saturni, F. G., Scherer, A., Schovanek, P., Schussler, F., Schwanke, U., Sergĳenko, O., Servillat, M., Siejkowski, H., Siqueira, C., Spencer, S., Stamerra, A., Stanič, S., Steppa, C., Stolarczyk, T., Suda, Y., Tavernier, T., Teshima, M., Tibaldo, L., Torres, D. F., Tothill, N., Vacula, M., Vallage, B., Vallania, P., van Eldik, C., Vázquez Acosta, M., Vecchi, M., Ventura, S., Vercellone, S., Viana, A., Vigorito, C. F., Vink, J., Vitale, V., Vodeb, V., Vorobiov, S., Vuillaume, T., Wagner, S. J., Walter, R., White, M., Wierzcholska, A., Will, M., Yamazaki, R., Yang, L., Yoshikoshi, T., Zacharias, M., Zaharĳas, G., Zavrtanik, D., Zavrtanik, M., and Cherenkov Telescope Array Collaboration
Subjects: photon, emission, acceleration, efficiency, Cherenkov Telescope Array, WIMP, diffusion, suppression, sensitivity, Navarro-Frenk-White profile, dark matter, photon, energy, flux, cosmic radiation, spectrum, energy, high, cloud, TeV, spectral, galaxy, nucleus, cosmic radiation
Abstract: A deep survey of the Large Magellanic Cloud at ~0.1-100TeV photon energies with the Cherenkov Telescope Array is planned. We assess the detection prospects based on a model for the emission of the galaxy, comprising the four known TeV emitters, mock populations of sources, and interstellar emission on galactic scales. We also assess the detectability of 30 Doradus and SN 1987A, and the constraints that can be derived on the nature of dark matter. The survey will allow for fine spectral studies of N157B, N132D, LMC P3, and 30 Doradus C, and half a dozen other sources should be revealed, mainly pulsar-powered objects. The remnant from SN 1987A could be detected if it produces cosmic-ray nuclei with a flat power-law spectrum at high energies, or with a steeper index 2.3-2.4 pending a flux increase by a factor >3-4 over ~2015-2035. Large-scale interstellar emission remains mostly out of reach of the survey if its >10GeV spectrum has a soft photon index ~2.7, but degree-scale 0.1-10TeV pion-decay emission could be detected if the cosmic-ray spectrum hardens above >100GeV. The 30 Doradus star-forming region is detectable if acceleration efficiency is on the order of 1-10% of the mechanical luminosity and diffusion is suppressed by two orders of magnitude within
Published: 2023
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196. H.E.S.S. follow-up observations of GRB221009A

Author: Aharonian, F., Benkhali, F. Ait, Aschersleben, J., Ashkar, H., Backes, M., Baktash, A., Barbosa Martins, V., Batzofin, R., Becherini, Y., Berge, D., Bernlohr, K., Bi, B., Bottcher, M., Boisson, C., Bolmont, J., de Bony de Lavergne, M., Borowska, J., Bouyahiaoui, M., Bradascio, F., Breuhaus, M., Brose, R., Brun, F., Bruno, B., Bulik, T., Burger-Scheidlin, C., Caroff, S., Casanova, S., Celic, J., Cerruti, M., Chand, T., Chandra, S., Chen, A., Chibueze, J., Chibueze, O., Cotter, G., Dai, S., Mbarubucyeye, Jean Damascene, Devin, J., Djannati-Atai, A., Dmytriiev, A., Doroshenko, V., Egberts, K., Einecke, S., Ernenwein, J.-P., Fegan, S., Fichet de Clairfontaine, G., Filipovic, M., Fontaine, G., Fußling, M., Funk, S., Gabici, S., Ghafourizadeh, S., Giavitto, G., Glawion, D., Glicenstein, J. F., Goswami, P., Grolleron, G., Grondin, M.-H., Hinton, J. A., Holch, T. L., Holler, M., Horns, D., Huang, Zhiqiu, Jamrozy, M., Jankowsky, F., Joshi, V., Jung-Richardt, I., Kasai, E., Katarzynski, K., Khatoon, R., Khelifi, B., Klúzniak, W., Komin, Nu., Konno, R., Kosack, K., Kostunin, D., Lang, R. G., Le Stum, S., Leitl, F., Lemiere, A., Lemoine-Goumard, M., Lenain, J.-P., Leuschner, F., Lohse, T., Lypova, I., Mackey, J., Malyshev, D., Marandon, V., Marchegiani, P., Marcowith, A., Martí-Devesa, G., Marx, R., Meyer, M., Mitchell, A., Mohrmann, L., Montanari, A., Moulin, E., Murach, T., Nakashima, K., de Naurois, M., Niemiec, J., Noel, A. Priyana, O'Brien, P., Ohm, S., Olivera-Nieto, L., de Ona Wilhelmi, E., Ostrowski, M., Panny, S., Panter, M., Parsons, R. D., Peron, G., Prokhorov, D. A., Prokoph, H., Puhlhofer, G., Punch, M., Quirrenbach, A., Reichherzer, P., Reimer, A., Reimer, O., Ren, H., Renaud, M., Reville, B., Rieger, F., Rowell, G., Rudak, B., Ruiz-Velasco, E., Sahakian, V., Salzmann, H., Santangelo, A., Sasaki, M., Schafer, J., Schussler, F., Schutte, H. M., Schwanke, U., Shapopi, J. N. S., Specovius, A., Spencer, S., Stawarz, L., Steenkamp, R., Steinmassl, S., Steppa, C., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Terrier, R., Tsuji, N., Uchiyama, Y., Vecchi, M., Venter, C., Vink, J., Wagner, S. J., White, R., Wierzcholska, A., Wong, Yu Wun, Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zech, A., Zhu, Sylvia Jiechen, Zywucka, And N., and H. E. S. S. Collaboration
Subjects: electron, atmosphere, correction, flux, ratio, flux, upper limit, gamma ray, burst, brightness, X-ray, flux, GeV, VHE, energy, high, 5/3, HESS, synchrotron, energy, flux
Abstract: GRB221009A is the brightest gamma-ray burst ever detected. To probe the very-high-energy (VHE, $>$100 GeV) emission, the High Energy Stereoscopic System (H.E.S.S.) began observations 53 hours after the triggering event, when the brightness of the moonlight no longer precluded observations. We derive differential and integral upper limits using H.E.S.S. data from the third, fourth, and ninth nights after the initial GRB detection, after applying atmospheric corrections. The combined observations yield an integral energy flux upper limit of $\Phi_\mathrm{UL}^{95\%} = 9.7 \times 10^{-12}~\mathrm{erg\,cm^{-2}\,s^{-1}}$ above $E_\mathrm{thr} = 650$ GeV. The constraints derived from the H.E.S.S. observations complement the available multiwavelength data. The radio to X-ray data are consistent with synchrotron emission from a single electron population, with the peak in the SED occurring above the X-ray band. Compared to the VHE-bright GRB190829A, the upper limits for GRB221009A imply a smaller gamma-ray to X-ray flux ratio in the afterglow. Even in the absence of a detection, the H.E.S.S. upper limits thus contribute to the multiwavelength picture of GRB221009A, effectively ruling out an IC dominated scenario.
Published: 2023
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197. HESS J1809$-$193: a halo of escaped electrons around a pulsar wind nebula?

Author: Aharonian, F., Benkhali, F. Ait, Aschersleben, J., Ashkar, H., Backes, M., Barbosa Martins, V., Batzofin, R., Becherini, Y., Berge, D., Böttcher, M., Boisson, C., Bolmont, J., Borowska, J., Bouyahiaoui, M., Bradascio, F., Breuhaus, M., Brose, R., Brun, F., Bruno, B., Bulik, T., Burger-Scheidlin, C., Bylund, T., Caroff, S., Casanova, S., Celic, J., Cerruti, M., Chambery, P., Chand, T., Chen, A., Chibueze, J., Chibueze, O., Mbarubucyeye, J. Damascene, Djannati-Ataï, A., Dmytriiev, A., Einecke, S., Ernenwein, J.-P., Feijen, K., Filipovic, M., Fontaine, G., Füßling, M., Funk, S., Gabici, S., Gallant, Y. A., Ghafourizadeh, S., Giavitto, G., Giunti, L., Glawion, D., Goswami, P., Grolleron, G., Grondin, M.-H., Haerer, L., Hinton, J. A., Hofmann, W., Holch, T. L., Holler, M., Horns, D., Huang, Zhiqiu, Jamrozy, M., Jankowsky, F., Joshi, V., Jung-Richardt, I., Kasai, E., Katarzynski, K., Khélifi, B., Klúzniak, W., Komin, Nu., Kosack, K., Kostunin, D., Lang, R. G., Le Stum, S., Leitl, F., Lemière, A., Lemoine-Goumard, M., Lenain, J.-P., Leuschner, F., Lohse, T., Luashvili, A., Lypova, I., Mackey, J., Malyshev, D., Marandon, V., Marchegiani, P., Marcowith, A., Marinos, P., Martí-Devesa, G., Marx, R., Mitchell, A., Moderski, R., Mohrmann, L., Montanari, A., Moulin, E., Muller, J., Nakashima, K., de Naurois, M., Niemiec, J., Noel, A. Priyana, Ohm, S., Olivera-Nieto, L., de Ona Wilhelmi, E., Ostrowski, M., Panny, S., Panter, M., Parsons, R. D., Prokhorov, D. A., Pühlhofer, G., Punch, M., Quirrenbach, A., Reichherzer, P., Reimer, A., Reimer, O., Renaud, M., Reville, B., Rieger, F., Rowell, G., Rudak, B., Sahakian, V., Santangelo, A., Sasaki, M., Schutte, H. M., Schwanke, U., Shapopi, J. N. S., Sol, H., Specovius, A., Spencer, S., Stawarz, Ł., Steenkamp, R., Steinmassl, S., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Terrier, R., Thorpe-Morgan, C., Tsirou, M., Tsuji, N., Uchiyama, Y., van Eldik, C., Vecchi, M., Veh, J., Venter, C., Vink, J., Wach, T., Wagner, S. J., White, R., Wierzcholska, A., Wong, Yu Wun, Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zech, A., Zouari, S., Żywucka, N., H. E. S. S. Collaboration, 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), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), 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'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 de Physique des Deux Infinis Bordeaux (LP2I - Bordeaux), Université de Bordeaux (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Particules de Montpellier (LUPM), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), and H.E.S.S.
Subjects: electron, dimension: 3, halo, FOS: Physical sciences, GeV, GLAST, VHE, dimension, HESS, supernova, TeV, cloud, pulsar, High Energy Astrophysical Phenomena (astro-ph.HE), energy: high, high, observatory, 3 [dimension], ddc:520, high [energy], spectral, time dependence, galaxy, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], HAWC, energy
Abstract: Astronomy and astrophysics 672, A103 (2023). doi:10.1051/0004-6361/202245459, Context. HESS J1809−193 is an unassociated very-high-energy γ-ray source located on the Galactic plane. While it has been connected to the nebula of the energetic pulsar PSR J1809−1917, supernova remnants and molecular clouds present in the vicinity also constitute possible associations. Recently, the detection of γ-ray emission up to energies of ∼100 TeV with the HAWC observatory has led to renewed interest in HESS J1809−193.Aims. We aim to understand the origin of the γ-ray emission of HESS J1809−193.Methods. We analysed 93.2 h of data taken on HESS J1809−193 above 0.27 TeV with the High Energy Stereoscopic System (H.E.S.S.), using a multi-component, three-dimensional likelihood analysis. In addition, we provide a new analysis of 12.5 yr of Fermi-LAT data above 1 GeV within the region of HESS J1809−193. The obtained results are interpreted in a time-dependent modelling framework.Results. For the first time, we were able to resolve the emission detected with H.E.S.S. into two components: an extended component (modelled as an elongated Gaussian with a 1-σ semi-major and semi-minor axis of ∼0.62° and ∼0.35°, respectively) that exhibits a spectral cutoff at ∼13 TeV, and a compact component (modelled as a symmetric Gaussian with a 1-σ radius of ∼0.1°) that is located close to PSR J1809−1917 and shows no clear spectral cutoff. The Fermi-LAT analysis also revealed extended γ-ray emission, on scales similar to that of the extended H.E.S.S. component.Conclusions. Our modelling indicates that based on its spectrum and spatial extent, the extended H.E.S.S. component is likely caused by inverse Compton emission from old electrons that form a halo around the pulsar wind nebula. The compact component could be connected to either the pulsar wind nebula or the supernova remnant and molecular clouds. Due to its comparatively steep spectrum, modelling the Fermi-LAT emission together with the H.E.S.S. components is not straightforward.Key words: acceleration of particles / radiation mechanisms: non-thermal / pulsars: individual: PSR J1809-1917 / gamma rays: general⋆ Corresponding authors; e-mail: contact.hess@hess-experiment.eu, Published by EDP Sciences, Les Ulis
Published: 2023
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198. Constraining the cosmic-ray pressure in the inner Virgo Cluster using H.E.S.S. observations of M 87

Author: Aharonian, F., Ait Benkhali, F., Arcaro, C., Aschersleben, J., Backes, M., Barbosa Martins, V., Batzofin, R., Becherini, Y., Berge, D., Bernlöhr, K., Bi, B., Böttcher, M., Boisson, C., Bolmont, J., Borowska, J., Bradascio, F., Breuhaus, M., Brose, R., Brun, F., Bruno, B., Bulik, T., Burger-Scheidlin, C., Bylund, T., Caroff, S., Casanova, S., Cecil, R., Celic, J., Cerruti, M., Chand, T., Chandra, S., Chen, A., Chibueze, J., Chibueze, O., Cotter, G., Damascene Mbarubucyeye, J., Djannati-Ataï, A., Egberts, K., Ernenwein, J.-P., Fichet de Clairfontaine, G., Filipovic, M., Fontaine, G., Füßling, M., Funk, S., Gabici, S., Ghafourizadeh, S., Giavitto, G., Glawion, D., Glicenstein, J. F., Goswami, P., Grolleron, G., Grondin, M.-H., Haerer, L., Haupt, M., Hermann, G., Hinton, J. A., Holch, T. L., Horns, D., Jamrozy, M., Jankowsky, F., Joshi, V., Jung-Richardt, I., Kasai, E., Katarzyński, K., Khatoon, R., Khélifi, B., Kluźniak, W., Komin, Nu., Kosack, K., Kostunin, D., Lang, R. G., Le Stum, S., Leitl, F., Lemière, A., Lemoine-Goumard, M., Lenain, J.-P., Leuschner, F., Lohse, T., Luashvili, A., Lypova, I., Mackey, J., Malyshev, D., Marandon, V., Marchegiani, P., Marcowith, A., Marinos, P., Martí-Devesa, G., Marx, R., Meyer, M., Mitchell, A., Moderski, R., Mohrmann, L., Montanari, A., Moulin, E., Muller, J., Nakashima, K., de Naurois, M., Niemiec, J., Priyana Noel, A., O’Brien, P., Ohm, S., Olivera-Nieto, L., de Ona Wilhelmi, E., Panny, S., Panter, M., Parsons, R. D., Peron, G., Pita, S., Prokhorov, D. A., Prokoph, H., Pühlhofer, G., Punch, M., Quirrenbach, A., Reichherzer, P., Reimer, A., Reimer, O., Renaud, M., Rieger, F., Rowell, G., Rudak, B., Ruiz-Velasco, E., Sahakian, V., Salzmann, H., Sanchez, D. A., Santangelo, A., Sasaki, M., Schäfer, J., Schüssler, F., Schwanke, U., Shapopi, J. N. S., Sol, H., Specovius, A., Spencer, S., Stawarz, Ł., Steenkamp, R., Steinmassl, S., Steppa, C., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Taylor, A. M., Terrier, R., Tsirou, M., Tsuji, N., Uchiyama, Y., van Eldik, C., van Soelen, B., Vecchi, M., Veh, J., Venter, C., Vink, J., Wach, T., Wagner, S. J., White, R., Wierzcholska, A., Wong, Y. W., Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zech, A., Zouari, S., Żywucka, N., HESS Collaboration, AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), 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'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), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des Deux Infinis Bordeaux (LP2I - Bordeaux), Université de Bordeaux (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Particules de Montpellier (LUPM), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), and H.E.S.S.
Subjects: gamma ray, emission, causality, VHE [gamma ray], gamma ray, VHE, cosmic radiation: energy, FOS: Physical sciences, energy, density, feedback, power spectrum, gamma ray: energy spectrum, Bayesian, rotation, thermal, cosmic radiation [p], energy [cosmic radiation], emission [gamma ray], HESS, TeV, cosmic radiation: pressure, energy: density, AGN, cluster, p, cosmic radiation, energy spectrum [gamma ray], High Energy Astrophysical Phenomena (astro-ph.HE), radio wave, cosmic radiation, energy, cosmic radiation, pressure, Astrophysics - Astrophysics of Galaxies, pressure [cosmic radiation], gamma ray: emission, VIRGO, gamma ray: VHE, p: cosmic radiation, Astrophysics of Galaxies (astro-ph.GA), ddc:520, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], density [energy]
Abstract: Astronomy and astrophysics 675, A138 (2023). doi:10.1051/0004-6361/202346056, The origin of the gamma-ray emission from M87 is currently a matter of debate. This work aims to localize the VHE (100 GeV-100 TeV) gamma-ray emission from M87 and probe a potential extended hadronic emission component in the inner Virgo Cluster. The search for a steady and extended gamma-ray signal around M87 can constrain the cosmic-ray energy density and the pressure exerted by the cosmic rays onto the intra-cluster medium, and allow us to investigate the role of the cosmic rays in the active galactic nucleus feedback as a heating mechanism in the Virgo Cluster. H.E.S.S. telescopes are sensitive to VHE gamma rays and have been utilized to observe M87 since 2004. We utilized a Bayesian block analysis to identify M87 emission states with H.E.S.S. observations from 2004 until 2021, dividing them into low, intermediate, and high states. Because of the causality argument, an extended ($\gtrsim$kpc) signal is allowed only in steady emission states. Hence, we fitted the morphology of the 120h low state data and found no significant gamma-ray extension. Therefore, we derived for the low state an upper limit of 58'(corresponding to $\approx$4.6kpc) in the extension of a single-component morphological model described by a rotationally symmetric 2D Gaussian model at 99.7% confidence level. Our results exclude the radio lobes ($\approx$30 kpc) as the principal component of the VHE gamma-ray emission from the low state of M87. The gamma-ray emission is compatible with a single emission region at the radio core of M87. These results, with the help of two multiple-component models, constrain the maximum cosmic-ray to thermal pressure ratio $X_{{CR,max.}}$$\lesssim$$0.32$ and the total energy in cosmic-ray protons (CRp) to $U_{CR}$$\lesssim$5$\times10^{58}$ erg in the inner 20kpc of the Virgo Cluster for an assumed CRp power-law distribution in momentum with spectral index $\alpha_{p}$=2.1., Published by EDP Sciences, Les Ulis
Published: 2023

199. A deep spectromorphological study of the γ-ray emission surrounding the young massive stellar cluster Westerlund 1

Author: Aharonian, F., Ashkar, H., Brose, R., Quirrenbach, A., Rauth, R., Reichherzer, P., Reimer, A., Reimer, O., Renaud, M., Reville, B., Rieger, F., Rowell, G., Rudak, B., Brun, F., Ruiz-Velasco, E., Sahakian, V., Salzmann, H., Sanchez, D. A., Santangelo, A., Sasaki, M., Schüssler, F., Schutte, H. M., Schwanke, U., Shapopi, J. N. S., Bulik, T., Specovius, A., Spencer, S., Stawarz, Ł., Steenkamp, R., Steinmassl, S., Steppa, C., Sushch, I., Suzuki, H., Takahashi, T., Tanaka, T., Burger-Scheidlin, C., Terrier, R., Thorpe-Morgan, C., Tsirou, M., Tsuji, N., Tuffs, R., Unbehaun, T., van Eldik, C., van Soelen, B., Vecchi, M., Veh, J., Cangemi, F., Venter, C., Vink, J., Wagner, S. J., White, R., Wierzcholska, A., Wong, Yu Wun, Zacharias, M., Zargaryan, D., Zdziarski, A. A., Zhu, S. J., Caroff, S., Zouari, S., Zywucka, N., Blackwell, R., Braiding, C., Burton, M., Cubuk, K., Filipovic, M., Tothill, N., Wong, G., H. E. S. S. Collaboration, Casanova, S., Cerruti, M., Chand, T., Chandra, S., Backes, M., Chen, A., Chibueze, O., Cristofari, P., Mbarubucyeye, J. Damascene, Djannati-Ataï, A., Ernenwein, J.-P., Feijen, K., de Clairfontaine, G. Fichet, Fontaine, G., Funk, S., Barbosa Martins, V., Gabici, S., Gallant, Y. A., Ghafourizadeh, S., Giavitto, G., Giunti, L., Glawion, D., Glicenstein, J. F., Goswami, P., Grondin, M.-H., Härer, L. K., Becherini, Y., Haupt, M., Hinton, J. A., Hörbe, M., Hofmann, W., Holch, T. L., Holler, M., Horns, D., Jamrozy, M., Joshi, V., Jung-Richardt, I., Berge, D., Kasai, E., Katarzynski, K., Katz, U., Khélifi, B., Klúzniak, W., Komin, Nu., Kosack, K., Kostunin, D., Mezek, G. Kukec, Lang, R. G., Bi, B., Le Stum, S., Lemière, A., Lemoine-Goumard, M., Lenain, J.-P., Leuschner, F., Lohse, T., Luashvili, A., Lypova, I., Mackey, J., Majumdar, J., Böttcher, M., Malyshev, D., Marandon, V., Marchegiani, P., Marcowith, A., Martí-Devesa, G., Marx, R., Maurin, G., Meyer, M., Mitchell, A., Moderski, R., de Bony de Lavergne, M., Mohrmann, L., Montanari, A., Moulin, E., Muller, J., Murach, T., Nakashima, K., de Naurois, M., Nayerhoda, A., Niemiec, J., Ohm, S., Bradascio, F., Olivera-Nieto, L., de Ona Wilhelmi, E., Ostrowski, M., Panny, S., Panter, M., Parsons, R. D., Peron, G., Prokhorov, D. A., Pühlhofer, G., Punch, M., High Energy Astrophys. & Astropart. Phys (API, FNWI), Astronomy, 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), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), 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 de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Particules de Montpellier (LUPM), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), Laboratoire de Physique des Deux Infinis Bordeaux (LP2I - Bordeaux), Université de Bordeaux (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), H.E.S.S., and H.E.S.S. Collaboration
Subjects: Astronomy and Astrophysics, gamma rays: general, shock waves, radiation mechanisms: non-thermal, non-thermal [radiation mechanisms], stars: massive, massive [stars], Space and Planetary Science, galaxies: star clusters: individual: Westerlund 1, HESS - Abteilung Hinton, ddc:520, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - High Energy Astrophysical Phenomena, general [gamma rays], star clusters: individual: Westerlund 1 [galaxies], acceleration of particles
Abstract: Astronomy and astrophysics 666, A124 (2022). doi:10.1051/0004-6361/202244323, Context. Young massive stellar clusters are extreme environments and potentially provide the means for efficient particle acceleration. Indeed, they are increasingly considered as being responsible for a significant fraction of cosmic rays (CRs) that are accelerated within the Milky Way. Westerlund 1, the most massive known young stellar cluster in our Galaxy, is a prime candidate for studying this hypothesis. While the very-high-energy $\gamma$-ray source HESS J1646−458 has been detected in the vicinity of Westerlund 1 in the past, its association could not be firmly identified.Aims. We aim to identify the physical processes responsible for the γ-ray emission around Westerlund 1 and thus to understand the role of massive stellar clusters in the acceleration of Galactic CRs better.Methods. Using 164 h of data recorded with the High Energy Stereoscopic System (H.E.S.S.), we carried out a deep spectromorphological study of the $\gamma$-ray emission of HESS J1646−458. We furthermore employed H I and CO observations of the region to infer the presence of gas that could serve as target material for interactions of accelerated CRs.Results. We detected large-scale (∼2° diameter) $\gamma$-ray emission with a complex morphology, exhibiting a shell-like structure and showing no significant variation with $\gamma$-ray energy. The combined energy spectrum of the emission extends to several tens of TeV, and it is uniform across the entire source region. We did not find a clear correlation of the $\gamma$-ray emission with gas clouds as identified through H I and CO observations.Conclusions. We conclude that, of the known objects within the region, only Westerlund 1 can explain the majority of the $\gamma$-ray emission. Several CR acceleration sites and mechanisms are conceivable and discussed in detail. While it seems clear that Westerlund 1 acts as a powerful particle accelerator, no firm conclusions on the contribution of massive stellar clusters to the flux of Galactic CRs in general can be drawn at this point., Published by EDP Sciences, Les Ulis
Published: 2022
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200. The camera of the fifth H.E.S.S. telescope. Part I: System description

Author: Bolmont, J., Corona, P., Gauron, P., Ghislain, P., Goffin, C., Guevara Riveros, L., Huppert, J.-F., Martineau-Huynh, O., Nayman, P., Parraud, J.-M., Tavernet, J.-P., Toussenel, F., Vincent, D., Vincent, P., Bertoli, W., Espigat, P., Punch, M., Besin, D., Delagnes, E., Glicenstein, J.-F., Moudden, Y., Venault, P., Zaghia, H., Brunetti, L., David, P.-Y., Dubois, J.-M., Fiasson, A., Geffroy, N., Gomes Monteiro, I., Journet, L., Krayzel, F., Lamanna, G., Le Flour, T., Lees, S., Lieunard, B., Maurin, G., Mugnier, P., Panazol, J-L., Prast, J., Chounet, L.-M., Degrange, B., Edy, E., Fontaine, G., Giebels, B., Hormigos, S., Khélifi, B., Manigot, P., Maritaz, P., de Naurois, M., Compin, M., Feinstein, F., Fernandez, D., Mehault, J., Rivoire, S., Royer, S., Sanguillon, M., and Vasileiadis, G.
Published: 2014
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