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Abramowski, Attila ; Aharonian, Felix A. ; Benkhali, Faical Ait ; Akhperjanian, A. G. ; Angüner, Ekrem Oǧuzhan ; Backes, Michael ; Balzer, Arnim ; Becherini, Yvonne ; Tjus, J. Becker ; Berge, David ; Bernhard, Sabrina ; Bernlöhr, K. ; Birsin, E. ; Blackwell, R. ; Boettcher, Markus ; Boisson, Catherine ; Bolmont, J. ; Bordas, Pol ; Bregeon, Johan ; Brun, Francois ; Brun, Pierre ; Bryan, Mark ; Bulik, Tomasz ; Carr, John ; Casanova, Sabrina ; Chakraborty, N. ; Chalme-Calvet, R. ; Chaves, Ryan C. G. ; Chen, Andrew ; Chretien, M. ; Colafrancesco, Sergio ; Cologna, Gabriele ; Conrad, Jan ; Couturier, C. ; Cui, Y. ; Davids, I. D. ; Degrange, B. ; Deil, C. ; deWilt, P. ; Djannati-Ataï, A. ; Domainko, W. ; Donath, A. ; Dubus, G. ; Dutson, K. ; Dyks, J. ; Dyrda, M. ; Edwards, T. ; Egberts, Kathrin ; Eger, P. ; Ernenwein, J. -P. ; Espigat, P. ; Farnier, C. ; Fegan, S. ; Feinstein, F. ; Fernandesl, M. V. ; Fernandez, D. ; Fiasson, A. ; Fontaine, G. ; Foerster, A. ; Fuessling, M. ; Gabici, S. ; Gajdus, M. ; Gallant, Y. A. ; Garrigoux, T. ; Giavitto, G. ; Giebels, B. ; Glicenstein, J. F. ; Gottschall, D. ; Goyal, A. ; Grondin, M. -H. ; Grudzinska, M. ; Hadasch, D. ; Haeffner, S. ; Hahn, J. ; Hawkes, J. ; Heinzelmann, G. ; Henri, G. ; Hermann, G. ; Hervet, O. ; Hillert, A. ; Hinton, James Anthony ; Hofmann, W. ; Hofverberg, P. ; Hoischen, Clemens ; Holler, M. ; Horns, D. ; Ivascenko, A. ; Jacholkowska, A. ; Jahn, C. ; Jamrozy, M. ; Janiak, M. ; Jankowsky, F. ; Jung-Richardt, I. ; Kastendieckl, M. A. ; Katarzynski, K. ; Katz, U. ; Kerszberg, D. ; Khelifi, B. ; Kieffer, M. ; Klepser, S. ; Klochkov, D. ; Kluzniak, W. ; Kolitzus, D. ; Komin, Nu. ; Kosack, K. ; Krakau, S. ; Krayzel, F. ; Krueger, P. P. ; Laffon, H. ; Lamanna, G. ; Lau, J. ; Lefaucheur, J. ; Lefranc, V. ; Lemiere, A. ; Lemoine-Goumard, M. ; Lenain, J. -P. ; Lohse, T. ; Lopatin, A. ; Lu, C. -C. ; Lui, R. ; Marandon, V. ; Marcowith, Alexandre ; Mariaud, C. ; Marx, R. ; Maurin, G. ; Maxted, N. ; Mayer, M. ; Meintjes, P. J. ; Menzler, U. ; Meyer, M. ; Mitchell, A. M. W. ; Moderski, R. ; Mohamed, M. ; Mora, K. ; Moulin, Emmanuel ; Murach, T. ; de Naurois, M. ; Niemiec, J. ; Oakes, L. ; Odaka, H. ; Oettl, S. ; Ohm, S. ; de Ona Wilhelmi, E. ; Opitz, B. ; Ostrowski, M. ; Oya, I. ; Panter, M. ; Parsons, R. D. ; Arribas, M. Paz ; Pekeur, N. W. ; Pelletier, G. ; Petrucci, P. -O. ; Peyaud, B. ; Pita, S. ; Poon, H. ; Prokoph, H. ; Puehlhofer, G. ; Punch, M. ; Quirrenbach, A. ; Raab, S. ; Reichardt, I. ; Reimer, A. ; Reimer, O. ; Renaud, M. ; de los Reyes, R. ; Rieger, F. ; Romoli, C. ; Rosier-Lees, S. ; Rowell, G. ; Rudak, B. ; Rulten, C. B. ; Sahakian, V. ; Salek, D. ; Sanchez, David M. ; Santangelo, Andrea ; Sasaki, M. ; Schlickeiser, R. ; Schuessler, F. ; Schulz, A. ; Schwanke, U. ; Schwemmer, S. ; Seyffert, A. S. ; Simoni, R. ; Sol, H. ; Spanier, F. ; Spengler, G. ; Spies, F. ; Stawarz, L. ; Steenkamp, R. ; Stegmann, Christian ; Stinzing, F. ; Stycz, K. ; Sushch, Iurii ; Tavernet, J. -P. ; Tavernier, T. ; Taylor, A. M. ; Terrier, R. ; Tluczykont, M. ; Trichard, C. ; Valerius, K. ; van der Walt, J. ; van Eldik, C. ; van Soelen, B. ; Vasileiadis, G. ; Veh, J. ; Venter, C. ; Viana, A. ; Vincent, P. ; Vink, J. ; Voisin, F. ; Voelk, H. J. ; Vuillaume, T. ; Wagner, S. J. ; Wagner, P. ; Wagner, R. M. ; Weidinger, M. ; Weitzel, Q. ; White, R. ; Wierzcholska, A. ; Willmann, P. ; Woernlein, A. ; Wouters, D. ; Yang, R. ; Zabalza, V. ; Zaborov, D. ; Zacharias, M. ; Zdziarski, A. A. ; Zech, Alraune ; Zefi, F. ; Zywucka, N.
Re-observations with the HESS telescope array of the very high-energy (VHE) source HESS J1018-589A that is coincident with the Fermi-LAT gamma-ray binary 1FGL J1018.6-5856 have resulted in a source detection significance of more than 9 sigma and the detection of variability (chi(2)/nu of 238.3/155) in the emitted gamma-ray flux. This variability confirms the association of HESS J1018-589A with the high-energy gamma-ray binary detected Fermi-LAT and also confirms the point-like source as a new VHE binary system. The spectrum of HESS J1018-589A is best fit with a power-law function with photon index Gamma = 2.20 +/- 0.14(stat) +/- 0.2(sys). Emission is detected up to similar to 20 TeV. The mean differential flux level is (2.9 +/- 0.4) x 10(-13) TeV-1 cm(-2) s(-1) at 1 TeV, equivalent to similar to 1% of the flux from the Crab Nebula at the same energy. Variability is clearly detected the night-by-night light curve. When folded on the orbital period of 16.58 days, the rebinned light curve peaks in phase with the observed X-ray high-energy phaseograms. The fit of the HESS phaseogram to a constant flux provides evidence of periodicity at the level of N-sigma > 3 sigma. The of the VHE phaseogram and measured spectrum suggest a low-inclination, low-eccentricity system with a modest impact from VHE gamma-ray due to pair production (tau less than or similar to 1 at 300 GeV).
Abdalla, Hassan E. ; Abramowski, A. ; Aharonian, Felix A. ; Benkhali, F. Ait ; Akhperjanian, A. G. ; Andersson, T. ; Anguener, E. O. ; Arakawa, M. ; Arrieta, M. ; Aubert, P. ; Backes, M. ; Balzer, A. ; Barnard, M. ; Becherini, Y. ; Tjus, J. Becker ; Berge, D. ; Bernhard, S. ; Bernloehr, K. ; Blackwell, R. ; Boettcher, M. ; Boisson, C. ; Bolmont, J. ; Bordas, Pol ; Bregeon, J. ; Brun, F. ; Brun, P. ; Bryan, M. ; Bilchele, M. ; Bulik, T. ; Capasso, M. ; Carr, J. ; Casanova, Sabrina ; Cerruti, M. ; Chakraborty, N. ; Chalme-Calvet, R. ; Chaves, R. C. G. ; Chen, A. ; Chevalier, J. ; Chretien, M. ; Coffaro, M. ; Colafrancesco, S. ; Cologna, G. ; Condon, B. ; Conrad, J. ; Cui, Y. ; Davids, I. D. ; Decock, J. ; Degrange, B. ; Deil, C. ; Devin, J. ; deWilt, P. ; Dirson, L. ; Djannati-Atai, A. ; Domainko, W. ; Donath, A. ; Dutson, K. ; Dyks, J. ; Edwards, T. ; Egberts, Kathrin ; Eger, P. ; Ernenwein, J. -P. ; Eschbach, S. ; Farnier, C. ; Fegan, S. ; Fernandes, M. V. ; Fiasson, A. ; Fontaine, G. ; Foerster, A. ; Funk, S. ; Fuessling, M. ; Gabici, S. ; Gajdus, M. ; Gallant, Y. A. ; Garrigoux, T. ; Giavitto, G. ; Giebels, B. ; Glicenstein, J. F. ; Gottschall, D. ; Goya, A. ; Grondin, M. -H. ; Hahn, J. ; Haupt, M. ; Hawkes, J. ; Heinzelmann, G. ; Henri, G. ; Hermann, G. ; Hervet, O. ; Hinton, J. A. ; Hofmann, W. ; Hoischen, Clemens ; Holler, M. ; Horns, D. ; Ivascenko, A. ; Iwasaki, H. ; Jacholkowska, A. ; Jamrozy, M. ; Janiak, M. ; Jankowsky, D. ; Jankowsky, F. ; Jingo, M. ; Jogler, T. ; Jouvin, L. ; Jung-Richardt, I. ; Kastendieck, M. A. ; Katarzynski, K. ; Katsuragawa, M. ; Katz, U. ; Kerszberg, D. ; Khangulyan, D. ; Khelifi, B. ; Kieffer, M. ; King, J. ; Klepser, S. ; Klochkov, D. ; Kluzniak, W. ; Kolitzus, D. ; Komin, Nu. ; Kosack, K. ; Krakau, S. ; Kraus, M. ; Krueger, P. P. ; Laffon, H. ; Lamanna, G. ; Lau, J. ; Lees, J. -P. ; Lefaucheur, J. ; Lefranc, V. ; Lemiere, A. ; Lemoine-Goumard, M. ; Lenain, J. -P. ; Leser, Eva ; Lohse, T. ; Lorentz, M. ; Liu, R. ; Lopez-Coto, R. ; Lypova, I. ; Marandon, V. ; Marcowith, Alexandre ; Mariaud, C. ; Marx, R. ; Maurin, G. ; Maxted, N. ; Mayer, M. ; Meintjes, P. J. ; Meyer, M. ; Mitche, A. M. W. ; Moderski, R. ; Mohamed, M. ; Mohrmann, L. ; Mora, K. ; Moulin, Emmanuel ; Murach, T. ; Nakashima, S. ; de Naurois, M. ; Niederwanger, F. ; Niemiec, J. ; Oakes, L. ; Odaka, H. ; Oettl, S. ; Ohm, S. ; Ostrowski, M. ; Oya, I. ; Padovani, M. ; Panter, M. ; Parsons, R. D. ; Arribas, M. Paz ; Pekeur, N. W. ; Pelletier, G. ; Perennes, C. ; Petrucci, P. -O. ; Peyaud, B. ; Piel, Q. ; Pita, S. ; Poon, H. ; Prokhorov, D. ; Prokoph, H. ; Puehlhofer, G. ; Punch, M. ; Quirrenbach, A. ; Raab, S. ; Reimer, A. ; Reimer, O. ; Renaud, M. ; de los Reyes, R. ; Richter, S. ; Rieger, F. ; Romoli, C. ; Rowell, G. ; Rudak, B. ; Rulten, C. B. ; Sahakian, V. ; Saito, S. ; Salek, D. ; Sanchez, D. A. ; Santangelo, Andrea ; Sasaki, M. ; Schlickeiser, R. ; Schuessler, F. ; Schulz, A. ; Schwanke, U. ; Schwemmer, S. ; Seglar-Arroyo, M. ; Settimo, M. ; Seyffert, A. S. ; Shafi, N. ; Shilon, I. ; Simoni, R. ; Sol, H. ; Spanier, F. ; Spengler, G. ; Spies, F. ; Stawarz, L. ; Steenkamp, R. ; Stegmann, Christian ; Stycz, K. ; Sushch, I. ; Takahashi, T. ; Tavernet, J. -P. ; Tavernier, T. ; Taylor, A. M. ; Terrier, R. ; Tibaldo, L. ; Tiziani, D. ; Tluczykont, M. ; Trichard, C. ; Tsuji, N. ; Tuffs, R. ; Uchiyama, Y. ; van der Walt, D. J. ; van Eldik, C. ; van Rensburg, C. ; van Soelen, B. ; Vasileiadis, G. ; Veh, J. ; Venter, C. ; Viana, A. ; Vincent, P. ; Vink, J. ; Voisin, F. ; Voelk, H. J. ; Vuillaume, T. ; Wadiasingh, Z. ; Wagner, S. J. ; Wagner, P. ; Wagner, R. M. ; White, R. ; Wierzcholska, A. ; Willmann, P. ; Woernlein, A. ; Wouters, D. ; Yang, R. ; Zabalza, V. ; Zaborov, D. ; Zacharias, M. ; Zanin, R. ; Zdziarski, A. A. ; Zech, Alraune ; Zefi, F. ; Ziegler, A. ; Zywucka, N.
Aims. We study gamma-ray emission from the shell-type supernova remnant (SNR) RXJ0852.0-4622 to better characterize its spectral properties and its distribution over the SNR. Methods. The analysis of an extended High Energy Spectroscopic System (H.E.S.S.) data set at very high energies (E > 100 GeV) permits detailed studies, as well as spatially resolved spectroscopy, of the morphology and spectrum of the whole RXJ0852.0-4622 region. The H.E.S.S. data are combined with archival data from other wavebands and interpreted in the framework of leptonic and hadronic models. The joint Fermi-LAT-H.E.S.S. spectrum allows the direct determination of the spectral characteristics of the parent particle population in leptonic and hadronic scenarios using only GeV-TeV data. Results. An updated analysis of the H.E.S.S. data shows that the spectrum of the entire SNR connects smoothly to the high-energy spectrum measured by Fermi-LAT. The increased data set makes it possible to demonstrate that the H.E.S.S. spectrum deviates significantly from a power law and is well described by both a curved power law and a power law with an exponential cutoff at an energy of E-cut = (6.7 +/- 1.2(stat) +/- 1.2(syst)) TeV. The joint Fermi-LAT-H.E.S.S. spectrum allows the unambiguous identification of the spectral shape as a power law with an exponential cutoff. No significant evidence is found for a variation of the spectral parameters across the SNR, suggesting similar conditions of particle acceleration across the remnant. A simple modeling using one particle population to model the SNR emission demonstrates that both leptonic and hadronic emission scenarios remain plausible. It is also shown that at least a part of the shell emission is likely due to the presence of a pulsar wind nebula around PSR J0855-4644.
Abdalla, Hassan E. ; Abramowski, A. ; Aharonian, Felix A. ; Benkhali, F. Ait ; Angüner, Ekrem Oǧuzhan ; Arakawa, M. ; Armand, C. ; Arrieta, M. ; Backes, M. ; Balzer, A. ; Barnard, M. ; Becherini, Y. ; Tjus, J. Becker ; Berge, D. ; Bernhard, S. ; Bernloehr, K. ; Blackwell, R. ; Boettcher, M. ; Boisson, C. ; Bolmont, J. ; Bonnefoy, S. ; Bordas, Pol ; Bregeon, J. ; Brun, F. ; Brun, P. ; Bryan, M. ; Buechele, M. ; Bulik, T. ; Capasso, M. ; Caroff, S. ; Carosi, A. ; Casanova, Sabrina ; Cerruti, M. ; Chakraborty, N. ; Chaves, R. C. G. ; Chen, A. ; Chevalier, J. ; Colafrancesco, S. ; Condon, B. ; Conrad, J. ; Davids, I. D. ; Decock, J. ; Deil, C. ; Devin, J. ; deWilt, P. ; Dirson, L. ; Djannati-Atai, A. ; Donath, A. ; Dyks, J. ; Edwards, T. ; Egberts, Kathrin ; Emery, G. ; Ernenwein, J. -P. ; Eschbach, S. ; Farnier, C. ; Fegan, S. ; Fernandes, M. V. ; Fiasson, A. ; Fontaine, G. ; Funk, S. ; Fuessling, M. ; Gabici, S. ; Gallant, Y. A. ; Garrigoux, T. ; Gate, F. ; Giavitto, G. ; Glawion, D. ; Glicenstein, J. F. ; Gottschall, D. ; Grondin, M. -H. ; Hahn, J. ; Haupt, M. ; Hawkes, J. ; Heinzelmann, G. ; Henri, G. ; Hermann, G. ; Hinton, J. A. ; Hofmann, W. ; Hoischen, Clemens ; Holch, T. L. ; Holler, M. ; Horns, D. ; Ivascenko, A. ; Iwasaki, H. ; Jacholkowska, A. ; Jamrozy, M. ; Jankowsky, D. ; Jankowsky, F. ; Jingo, M. ; Jouvin, L. ; Jung-Richardt, I. ; Kastendieck, M. A. ; Katarzynski, K. ; Katsuragawa, M. ; Katz, U. ; Kerszberg, D. ; Khangulyan, D. ; Khelifi, B. ; King, J. ; Klepser, S. ; Klochkov, D. ; Kluzniak, W. ; Komin, Nu. ; Kosack, K. ; Krakau, S. ; Kraus, M. ; Kruger, P. P. ; Laffon, H. ; Lamanna, G. ; Lau, J. ; Lefaucheur, J. ; Lemiere, A. ; Lemoine-Goumard, M. ; Lenain, J. -P. ; Leser, Eva ; Lohse, T. ; Lorentz, M. ; Liu, R. ; Lopez-Coto, R. ; Lypova, I. ; Malyshev, D. ; Marandon, V. ; Marcowith, Alexandre ; Mariaud, C. ; Marx, R. ; Maurin, G. ; Maxted, N. ; Mayer, M. ; Meintjes, P. J. ; Meyer, M. ; Mitchell, A. M. W. ; Moderski, R. ; Mohamed, M. ; Mohrmann, L. ; Mora, K. ; Moulin, Emmanuel ; Murach, T. ; Nakashima, S. ; de Naurois, M. ; Ndiyavala, H. ; Niederwanger, F. ; Niemiec, J. ; Oakes, L. ; Odaka, H. ; Ohm, S. ; Ostrowski, M. ; Oya, I. ; Padovani, M. ; Panter, M. ; Parsons, R. D. ; Pekeur, N. W. ; Pelletier, G. ; Perennes, C. ; Petrucci, P. -O. ; Peyaud, B. ; Piel, Q. ; Pita, S. ; Poireau, V. ; Prokhorov, D. A. ; Prokoph, H. ; Puehlhofer, G. ; Punch, M. ; Quirrenbach, A. ; Raab, S. ; Rauth, R. ; Reimer, A. ; Reimer, O. ; Renaud, M. ; de los Reyes, R. ; Rieger, F. ; Rinchiuso, L. ; Romoli, C. ; Rowell, G. ; Rudak, B. ; Rulten, C. B. ; Sahakian, V. ; Saito, S. ; Sanchez, D. A. ; Santangelo, Andrea ; Sasaki, M. ; Schlickeiser, R. ; Schussler, F. ; Schulz, A. ; Schwanke, U. ; Schwemmer, S. ; Seglar-Arroyo, M. ; Seyffert, A. S. ; Shafi, N. ; Shilon, I. ; Shiningayamwe, K. ; Simoni, R. ; Sol, H. ; Spanier, F. ; Spir-Jacob, M. ; Stawarz, L. ; Steenkamp, R. ; Stegmann, Christian ; Steppa, Constantin Beverly ; Sushch, I. ; Takahashi, T. ; Tavernet, J. -P. ; Tavernier, T. ; Taylor, A. M. ; Terrier, R. ; Tibaldo, L. ; Tiziani, D. ; Tluczykont, M. ; Trichard, C. ; Tsirou, M. ; Tsuji, N. ; Tuffs, R. ; Uchiyama, Y. ; van der Walt, D. J. ; van Eldik, C. ; van Rensburg, C. ; van Soelen, B. ; Vasileiadis, G. ; Veh, J. ; Venter, C. ; Viana, A. ; Vincent, P. ; Vink, J. ; Voisin, F. ; Voelk, H. J. ; Vuillaume, T. ; Wadiasingh, Z. ; Wagner, S. J. ; Wagner, P. ; Wagner, R. M. ; White, R. ; Wierzcholska, A. ; Willmann, P. ; Woernlein, A. ; Wouters, D. ; Yang, R. ; Zaborov, D. ; Zacharias, M. ; Zanin, R. ; Zdziarski, A. A. ; Zech, Alraune ; Zefi, F. ; Ziegler, A. ; Zorn, J. ; Zywucka, N. ; Enokiya, R. ; Fukui, Y. ; Hayakawa, T. ; Okuda, T. ; Torii, K. ; Yamamoto, H.
The H.E.S.S. Collaboration has discovered a new very high energy (VHE, E > 0.1 TeV) gamma-ray source, HESS J1741-302, located in the Galactic plane. Despite several attempts to constrain its nature, no plausible counterpart has been found so far at X-ray and MeV/GeV gamma-ray energies, and the source remains unidentified. An analysis of 145-h of observations of HESS J1741-302 at VHEs has revealed a steady and relatively weak TeV source (similar to 1% of the Crab Nebula flux), with a spectral index of Gamma = 2.3 +/- 0.2(stat) +/- 0.2(sys), extending to energies up to 10 TeV without any clear signature of a cut-off. In a hadronic scenario, such a spectrum implies an object with particle acceleration up to energies of several hundred TeV. Contrary to most H.E.S.S. unidentified sources, the angular size of HESS J1741-302 is compatible with the H.E.S.S. point spread function at VHEs, with an extension constrained to be below 0.068 degrees at a 99% confidence level. The gamma-ray emission detected by H.E.S.S. can be explained both within a hadronic scenario, due to collisions of protons with energies of hundreds of TeV with dense molecular clouds, and in a leptonic scenario, as a relic pulsar wind nebula, possibly powered by the middle-aged (20 kyr) pulsar PSR B1737-30. A binary scenario, related to the compact radio source 1LC 358.266+0.038 found to be spatially coincident with the best fit position of HESS J1741-302, is also envisaged.
Abdalla, Hassan E. ; Abramowski, A. ; Aharonian, Felix A. ; Benkhali, F. Ait ; Akhperjanian, A. G. ; Andersson, T. ; Anguener, E. O. ; Arakawa, M. ; Arrieta, M. ; Aubert, P. ; Backes, M. ; Balzer, A. ; Barnard, M. ; Becherini, Y. ; Tjus, J. Becker ; Berge, D. ; Bernhard, S. ; Bernloehr, K. ; Blackwell, R. ; Bottcher, M. ; Boisson, C. ; Bolmont, J. ; Bordas, Pol ; Bregeon, J. ; Brun, F. ; Brun, P. ; Bryan, M. ; Buechele, M. ; Bulik, T. ; Capasso, M. ; Carr, J. ; Casanova, Sabrina ; Cerruti, M. ; Chakraborty, N. ; Chalme-Calvet, R. ; Chaves, R. C. G. ; Chen, A. ; Chevalier, J. ; Chretien, M. ; Coffaro, M. ; Colafrancesco, S. ; Cologna, G. ; Condon, B. ; Conrad, J. ; Cui, Y. ; Davids, I. D. ; Decock, J. ; Degrange, B. ; Deil, C. ; Devin, J. ; deWilt, P. ; Dirson, L. ; Djannati-Atai, A. ; Domainko, W. ; Donath, A. ; Dutson, K. ; Dyks, J. ; Edwards, T. ; Egberts, Kathrin ; Eger, P. ; Ernenwein, J. -P. ; Eschbach, S. ; Farnier, C. ; Fegan, S. ; Fernandes, M. V. ; Fiasson, A. ; Fontaine, G. ; Foerster, A. ; Funk, S. ; Fuessling, M. ; Gabici, S. ; Gajdus, M. ; Gallant, Y. A. ; Garrigoux, T. ; Giavitto, G. ; Giebels, B. ; Glicenstein, J. F. ; Gottschall, D. ; Goyal, A. ; Grondin, M. -H. ; Hahn, J. ; Haupt, M. ; Hawkes, J. ; Heinzelmann, G. ; Henri, G. ; Hermann, G. ; Hervet, O. ; Hinton, J. A. ; Hofmann, W. ; Hoischen, Clemens ; Holler, M. ; Horns, D. ; Ivascenko, A. ; Iwasaki, H. ; Jacholkowska, A. ; Jamrozy, M. ; Janiak, M. ; Jankowsky, D. ; Jankowsky, F. ; Jingo, M. ; Jogler, T. ; Jouvin, L. ; Jung-Richardt, I. ; Kastendieck, M. A. ; Katarzynski, K. ; Katsuragawa, M. ; Katz, U. ; Kerszberg, D. ; Khangulyan, D. ; Khelifi, B. ; Kieffer, M. ; King, J. ; Klepser, S. ; Klochkov, D. ; Kluzniak, W. ; Kolitzus, D. ; Komin, Nu. ; Kosack, K. ; Krakau, S. ; Kraus, M. ; Kruger, P. P. ; Laffon, H. ; Lamanna, G. ; Lau, J. ; Lees, J. -P. ; Lefaucheur, J. ; Lefranc, V. ; Lemiere, A. ; Lemoine-Goumard, M. ; Lenain, J. -P. ; Leser, Eva ; Lohse, T. ; Lorentz, M. ; Liu, R. ; Lopez-Coto, R. ; Lypova, I. ; Marandon, V. ; Marcowith, Alexandre ; Mariaud, C. ; Marx, R. ; Maurin, G. ; Maxted, N. ; Mayer, M. ; Meintjes, P. J. ; Meyer, M. ; Mitchell, A. M. W. ; Moderski, R. ; Mohamed, M. ; Mohrmann, L. ; Mora, K. ; Moulin, Emmanuel ; Murach, T. ; Nakashima, S. ; de Naurois, M. ; Niederwanger, F. ; Niemiec, J. ; Oakes, L. ; Odaka, H. ; Oettl, S. ; Ohm, S. ; Ostrowski, M. ; Oya, I. ; Padovani, M. ; Panter, M. ; Parsons, R. D. ; Pekeur, N. W. ; Pelletier, G. ; Perennes, C. ; Petrucci, P. -O. ; Peyaud, B. ; Piel, Q. ; Pita, S. ; Poon, H. ; Prokhorov, D. ; Prokoph, H. ; Puehlhofer, G. ; Punch, M. ; Quirrenbach, A. ; Raab, S. ; Reimer, A. ; Reimer, O. ; Renaud, M. ; de los Reyes, R. ; Richter, S. ; Rieger, F. ; Romoli, C. ; Rowell, G. ; Rudak, B. ; Rulten, C. B. ; Sahakian, V. ; Saito, S. ; Salek, D. ; Sanchez, D. A. ; Santangelo, Andrea ; Sasaki, M. ; Schlickeiser, R. ; Schussler, F. ; Schulz, A. ; Schwanke, U. ; Schwemmer, S. ; Seglar-Arroyo, M. ; Settimo, M. ; Seyffert, A. S. ; Shafi, N. ; Shilon, I. ; Simoni, R. ; Sol, H. ; Spanier, F. ; Spengler, G. ; Spies, F. ; Stawarz, L. ; Steenkamp, R. ; Stegmann, Christian Michael ; Stycz, K. ; Sushch, I. ; Takahashi, T. ; Tavernet, J. -P. ; Tavernier, T. ; Taylor, A. M. ; Terrier, R. ; Tibaldo, L. ; Tiziani, D. ; Tluczykont, M. ; Trichard, C. ; Tsuji, N. ; Tuffs, R. ; Uchiyama, Y. ; van der Walt, D. J. ; van Eldik, C. ; van Rensburg, C. ; van Soelen, B. ; Vasileiadis, G. ; Veh, J. ; Venter, C. ; Viana, A. ; Vincent, P. ; Vink, J. ; Voisin, F. ; Voelk, H. J. ; Vuillaume, T. ; Wadiasingh, Z. ; Wagner, S. J. ; Wagner, P. ; Wagner, R. M. ; White, R. ; Wierzcholska, A. ; Willmann, P. ; Woernlein, A. ; Wouters, D. ; Yang, R. ; Zabalza, V. ; Zaborov, D. ; Zacharias, M. ; Zanin, R. ; Zdziarski, A. A. ; Zech, Alraune ; Zefi, F. ; Ziegler, A. ; Zywucka, N.
Context. Runaway stars form bow shocks by ploughing through the interstellar medium at supersonic speeds and are promising sources of non-thermal emission of photons. One of these objects has been found to emit non-thermal radiation in the radio band. This triggered the development of theoretical models predicting non-thermal photons from radio up to very-high-energy (VHE, E >= 0.1 TeV) gamma rays. Subsequently, one bow shock was also detected in X-ray observations. However, the data did not allow discrimination between a hot thermal and a non-thermal origin. Further observations of different candidates at X-ray energies showed no evidence for emission at the position of the bow shocks either. A systematic search in the Fermi-LAT energy regime resulted in flux upper limits for 27 candidates listed in the E-BOSS catalogue. Aims. Here we perform the first systematic search for VHE gamma-ray emission from bow shocks of runaway stars. Methods. Using all available archival H.E.S.S. data we search for very-high-energy gamma-ray emission at the positions of bow shock candidates listed in the second E-BOSS catalogue release. Out of the 73 bow shock candidates in this catalogue, 32 have been observed with H.E.S.S. Results. None of the observed 32 bow shock candidates in this population study show significant emission in the H.E.S.S. energy range. Therefore, flux upper limits are calculated in five energy bins and the fraction of the kinetic wind power that is converted into VHE gamma rays is constrained. Conclusions. Emission from stellar bow shocks is not detected in the energy range between 0.14 and 18 TeV. The resulting upper limits constrain the level of VHE gamma-ray emission from these objects down to 0.1-1% of the kinetic wind energy.
Abdalla, Hassan E. ; Abramowski, A. ; Aharonian, Felix A. ; Benkhali, F. Ait ; Akhperjanian, A. G. ; Andersson, T. ; Anguener, E. O. ; Arakawa, M. ; Arrieta, M. ; Aubert, P. ; Backes, M. ; Balzer, A. ; Barnard, M. ; Becherini, Y. ; Tjus, J. Becker ; Berge, D. ; Bernhard, S. ; Bernloehr, K. ; Blackwell, R. ; Boettcher, M. ; Boisson, C. ; Bolmont, J. ; Bonnefoy, S. ; Bordas, Pol ; Bregeon, J. ; Brun, F. ; Brun, P. ; Bryan, M. ; Buechele, M. ; Bulik, T. ; Capasso, M. ; Carr, J. ; Casanova, Sabrina ; Cerruti, M. ; Chakraborty, N. ; Chaves, R. C. G. ; Chen, A. ; Chevalier, J. ; Coffaro, M. ; Colafrancesco, S. ; Cologna, G. ; Condon, B. ; Conrad, J. ; Cui, Y. ; Davids, I. D. ; Decock, J. ; Degrange, B. ; Deil, C. ; Devin, J. ; deWilt, P. ; Dirson, L. ; Djannati-Atai, A. ; Domainko, W. ; Donath, A. ; Dutson, K. ; Dyks, J. ; Edwards, T. ; Egberts, Kathrin ; Eger, P. ; Ernenwein, J. -P. ; Eschbach, S. ; Farnier, C. ; Fegan, S. ; Fernandes, M. V. ; Fiasson, A. ; Fontaine, G. ; Foerster, A. ; Funk, S. ; Fuessling, M. ; Gabici, S. ; Gajdus, M. ; Gallant, Y. A. ; Garrigoux, T. ; Giavitto, G. ; Giebels, B. ; Glicenstein, J. F. ; Gottschall, D. ; Goyal, A. ; Grondin, M. -H. ; Hahn, J. ; Haupt, M. ; Hawkes, J. ; Heinzelmann, G. ; Henri, G. ; Hermann, G. ; Hervet, O. ; Hinton, J. A. ; Hofmann, W. ; Hoischen, Clemens ; Holch, T. L. ; Holler, M. ; Horns, D. ; Ivascenko, A. ; Iwasaki, H. ; Jacholkowska, A. ; Jamrozy, M. ; Janiak, M. ; Jankowsky, D. ; Jankowsky, F. ; Jingo, M. ; Jogler, T. ; Jouvin, L. ; Jung-Richardt, I. ; Kastendieck, M. A. ; Katarzynski, K. ; Katsuragawa, M. ; Katz, U. ; Kerszberg, D. ; Khangulyan, D. ; Khelifi, B. ; King, J. ; Klepser, S. ; Klochkov, D. ; Kluzniak, W. ; Kolitzus, D. ; Komin, Nu. ; Kosack, K. ; Krakau, S. ; Kraus, M. ; Krueger, P. P. ; Laffon, H. ; Lamanna, G. ; Lau, J. ; Lees, J. -P. ; Lefaucheur, J. ; Lefranc, V. ; Lemiere, A. ; Lemoine-Goumard, M. ; Lenain, J. -P. ; Leser, Eva ; Lohse, T. ; Lorentz, M. ; Liu, R. ; Lopez-Coto, R. ; Lypova, I. ; Marandon, V. ; Marcowith, Alexandre ; Mariaud, C. ; Marx, R. ; Maurin, G. ; Maxted, N. ; Mayer, M. ; Meintjes, P. J. ; Meyer, M. ; Mitche, A. M. W. ; Moderski, R. ; Mohamed, M. ; Mohrmann, L. ; Mora, K. ; Moulin, Emmanuel ; Murach, T. ; Nakashima, S. ; de Naurois, M. ; Niederwanger, F. ; Niemiec, J. ; Oakes, L. ; Odaka, H. ; Oettl, S. ; Ohm, S. ; Ostrowski, M. ; Oya, I. ; Padovani, M. ; Panter, M. ; Parsons, R. D. ; Pekeur, N. W. ; Pelletier, G. ; Perennes, C. ; Petrucci, P. -O. ; Peyaud, B. ; Piel, Q. ; Pita, S. ; Poon, H. ; Prokhorov, D. ; Prokoph, H. ; Puehlhofer, G. ; Punch, M. ; Quirrenbach, A. ; Raab, S. ; Reimer, A. ; Reimer, O. ; Renaud, M. ; de los Reyes, R. ; Richter, S. ; Rieger, F. ; Romoli, C. ; Rowell, G. ; Rudak, B. ; Rulten, C. B. ; Sahakian, V. ; Saito, S. ; Salek, D. ; Sanchez, D. A. ; Santangelo, Andrea ; Sasaki, M. ; Schlickeiser, R. ; Schuessler, F. ; Schulz, A. ; Schwanke, U. ; Schwemmer, S. ; Seglar-Arroyo, M. ; Settimo, M. ; Seyffert, A. S. ; Shafi, N. ; Shilon, I. ; Simoni, R. ; Sol, H. ; Spanier, F. ; Spengler, G. ; Spies, F. ; Stawarz, L. ; Steenkamp, R. ; Stegmann, Christian ; Stycz, K. ; Sushch, I. ; Takahashi, T. ; Tavernet, J. -P. ; Tavernier, T. ; Taylor, A. M. ; Terrier, R. ; Tibaldo, L. ; Tiziani, D. ; Tluczykont, M. ; Trichard, C. ; Tsuji, N. ; Tuffs, R. ; Uchiyama, Y. ; van der Wale, D. J. ; van Eldik, C. ; van Rensburg, C. ; van Soelen, B. ; Vasileiadis, G. ; Veh, J. ; Venter, C. ; Viana, A. ; Vincent, P. ; Vink, J. ; Voisin, F. ; Voelk, H. J. ; Vuillaume, T. ; Wadiasingh, Z. ; Wagner, S. J. ; Wagner, P. ; Wagner, R. M. ; White, R. ; Wierzcholska, A. ; Willmann, P. ; Woernlein, A. ; Wouters, D. ; Yang, R. ; Zabalza, V. ; Zaborov, D. ; Zacharias, M. ; Zanin, R. ; Zdziarski, A. A. ; Zech, Alraune ; Zefi, F. ; Ziegler, A. ; Zywucka, N. ; Bamba, A. ; Fukui, Y. ; Sano, H. ; Yoshiike, S.
A search for new supernova remnants (SNRs) has been conducted using TeV gamma-ray data from the H.E.S.S. Galactic plane survey. As an identification criterion, shell morphologies that are characteristic for known resolved TeV SNRs have been used. Three new SNR candidates were identified in the H.E.S.S. data set with this method. Extensive multiwavelength searches for counterparts were conducted. A radio SNR candidate has been identified to be a counterpart to HESS J1534-571. The TeV source is therefore classified as a SNR. For the other two sources, HESS J1614-518 and HESS J1912 + 101, no identifying counterparts have been found, thus they remain SNR candidates for the time being. TeV-emitting SNRs are key objects in the context of identifying the accelerators of Galactic cosmic rays. The TeV emission of the relativistic particles in the new sources is examined in view of possible leptonic and hadronic emission scenarios, taking the current multiwavelength knowledge into account.
Abdalla, Hassan E. ; Abramowski, Attila ; Aharonian, Felix A. ; Benkhali, Faical Ait ; Akhperjanian, A. G. ; Andersson, T. ; Angüner, Ekrem Oǧuzhan ; Arrieta, M. ; Aubert, Pierre ; Backes, Michael ; Balzer, Arnim ; Barnard, Michelle ; Becherini, Yvonne ; Tjus, J. Becker ; Berge, David ; Bernhard, Sabrina ; Bernlöhr, K. ; Birsin, E. ; Blackwell, R. ; Boettcher, Markus ; Boisson, Catherine ; Bolmont, J. ; Bordas, Pol ; Bregeon, Johan ; Brun, Francois ; Brun, Pierre ; Bryan, Mark ; Bulik, Tomasz ; Capasso, M. ; Carr, John ; Casanova, Sabrina ; Chakraborty, N. ; Chalme-Calvet, R. ; Chaves, Ryan C. G. ; Chen, Andrew ; Chevalier, J. ; Chretien, M. ; Colafrancesco, Sergio ; Cologna, Gabriele ; Condon, B. ; Conrad, Jan ; Couturier, C. ; Cui, Y. ; Davids, I. D. ; Degrange, B. ; Deil, C. ; Devin, J. ; de Wilt, P. ; Djannati-Ataie, A. ; Domainko, W. ; Donath, A. ; Dubus, G. ; Dutson, K. ; Dyks, J. ; Dyrda, M. ; Edwards, T. ; Egberts, Kathrin ; Eger, P. ; Ernenwein, J. -P. ; Eschbach, S. ; Farnier, C. ; Fegan, S. ; Fernandes, M. V. ; Fiasson, A. ; Fontaine, G. ; Foerster, A. ; Funk, S. ; Fuessling, M. ; Gabici, S. ; Gajdus, M. ; Gallant, Y. A. ; Garrigoux, T. ; Giavitto, G. ; Giebels, B. ; Glicenstein, J. F. ; Gottschall, D. ; Goyal, A. ; Grondin, M. -H. ; Grudzinska, M. ; Hadasch, D. ; Hahn, J. ; Hawkes, J. ; Heinzelmann, G. ; Henri, G. ; Hermann, G. ; Hervet, O. ; Hillert, A. ; Hinton, James Anthony ; Hofmann, W. ; Hoischen, Clemens ; Holler, M. ; Horns, D. ; Ivascenko, A. ; Jacholkowska, A. ; Jamrozy, M. ; Janiak, M. ; Jankowsky, D. ; Jankowsky, F. ; Jingo, M. ; Jogler, T. ; Jouvin, L. ; Jung-Richardt, I. ; Kastendieck, M. A. ; Katarzynski, K. ; Katz, U. ; Kerszberg, D. ; Khelifi, B. ; Kieffer, M. ; King, J. ; Klepser, S. ; Klochkov, D. ; Kluzniak, W. ; Kolitzus, D. ; Komin, Nu. ; Kosack, K. ; Krakau, S. ; Kraus, M. ; Krayzel, F. ; Krueger, P. P. ; Laffon, H. ; Lamanna, G. ; Lau, J. ; Lees, J. -P. ; Lefaucheur, J. ; Lefranc, V. ; Lemiere, A. ; Lemoine-Goumard, M. ; Lenain, J. -P. ; Leser, Eva ; Liu, R. ; Lohse, T. ; Lorentz, M. ; Lypova, I. ; Marandon, V. ; Marcowith, Alexandre ; Mariaud, C. ; Marx, R. ; Maurin, G. ; Maxted, N. ; Mayer, Michael ; Meintjes, P. J. ; Meyer, M. ; Mitchell, A. M. W. ; Moderski, R. ; Mohamed, M. ; Mora, K. ; Moulin, Emmanuel ; Murach, T. ; de Naurois, M. ; Niederwanger, F. ; Niemiec, J. ; Oakes, L. ; Odaka, H. ; Ohm, S. ; Ostrowski, M. ; Oettl, S. ; Oya, I. ; Padovani, M. ; Panter, M. ; Parsons, R. D. ; Arribas, M. Paz ; Pekeur, N. W. ; Pelletier, G. ; Perennes, C. ; Petrucci, P. -O. ; Peyaud, B. ; Pita, S. ; Poon, H. ; Prokhorov, D. ; Prokoph, H. ; Puehlhofer, G. ; Punch, M. ; Quirrenbach, A. ; Raab, S. ; Reimer, A. ; Reimer, O. ; Renaud, M. ; Reyes, R. de los ; Rieger, F. ; Romoli, C. ; Rosier-Lees, S. ; Rowell, G. ; Rudak, B. ; Rulten, C. B. ; Sahakian, V. ; Salek, D. ; Sanchez, David M. ; Santangelo, Andrea ; Sasaki, M. ; Schlickeiser, R. ; Schuessler, F. ; Schulz, A. ; Schwanke, U. ; Schwemmer, S. ; Settimo, M. ; Seyffert, A. S. ; Shafi, N. ; Shilon, I. ; Simoni, R. ; Sol, H. ; Spanier, F. ; Spengler, G. ; Spies, F. ; Stawarz, L. ; Steenkamp, R. ; Stegmann, Christian ; Stinzing, F. ; Stycz, K. ; Sushch, Iurii ; Tavernet, J. -P. ; Tavernier, T. ; Taylor, A. M. ; Terrier, R. ; Tibaldo, L. ; Tluczykont, M. ; Trichard, C. ; Tuffs, R. ; van der Walt, J. ; van Eldik, C. ; van Soelen, B. ; Vasileiadis, G. ; Veh, J. ; Venter, C. ; Viana, A. ; Vincent, P. ; Vink, J. ; Voisin, F. ; Voelk, H. J. ; Vuillaume, T. ; Wadiasingh, Z. ; Wagner, S. J. ; Wagner, P. ; Wagner, R. M. ; White, R. ; Wierzcholska, A. ; Willmann, P. ; Woernlein, A. ; Wouters, D. ; Yang, R. ; Zabalza, V. ; Zaborov, D. ; Zacharias, M. ; Zdziarski, A. A. ; Zech, Alraune ; Zefi, F. ; Ziegler, A. ; Zywucka, N.
A search for dark matter linelike signals iss performed in the vicinity of the Galactic Center by the H.E.S.S. experiment on observational data taken in 2014. An unbinned likelihood analysis iss developed to improve the sensitivity to linelike signals. The upgraded analysis along with newer data extend the energy coverage of the previous measurement down to 100 GeV. The 18 h of data collected with the H.E.S.S. array allow one to rule out at 95% C.L. the presence of a 130 GeV line (at l = -1.5 degrees, b = 0 degrees and for a dark matter profile centered at this location) previously reported in Fermi-LAT data. This new analysis overlaps significantly in energy with previous Fermi-LAT and H.E.S.S. results. No significant excess associated with dark matter annihilations was found in the energy range of 100 GeV to 2 TeV and upper limits on the gamma-ray flux and the velocity weighted annihilation cross section are derived adopting an Einasto dark matter halo profile. Expected limits for present and future large statistics H.E.S.S. observations are also given.
Abramowski, Attila ; Aharonian, Felix A. ; Benkhali, Faical Ait ; Akhperjanian, A. G. ; Angüner, Ekrem Oǧuzhan ; Backes, Michael ; Balzer, Arnim ; Becherini, Yvonne ; Tjus, J. Becker ; Berge, David ; Bernhard, Sabrina ; Bernlöhr, K. ; Birsin, E. ; Blackwell, R. ; Boettcher, Markus ; Boisson, Catherine ; Bolmont, J. ; Bordas, Pol ; Bregeon, Johan ; Brun, Francois ; Brun, Pierre ; Bryan, Mark ; Bulik, Tomasz ; Carr, John ; Casanova, Sabrina ; Chakraborty, N. ; Chalme-Calvet, R. ; Chaves, Ryan C. G. ; Chen, Andrew ; Chretien, M. ; Colafrancesco, Sergio ; Cologna, Gabriele ; Conrad, Jan ; Couturier, C. ; Cui, Y. ; Davids, I. D. ; Degrange, B. ; Deil, C. ; deWilt, P. ; Djannati-Ata, A. ; Domainko, W. ; Donath, A. ; Dubus, G. ; Dutson, K. ; Dyks, J. ; Dyrda, M. ; Edwards, T. ; Egberts, Kathrin ; Eger, P. ; Ernenwein, J-P. ; Espigat, P. ; Farnier, C. ; Fegan, S. ; Feinstein, F. ; Fernandes, M. V. ; Fernandez, D. ; Fiasson, A. ; Fontaine, G. ; Foerster, A. ; Fuessling, M. ; Gabici, S. ; Gajdus, M. ; Gallant, Y. A. ; Garrigoux, T. ; Giavitto, G. ; Giebels, B. ; Glicenstein, J. F. ; Gottschall, D. ; Goyal, A. ; Grondin, M-H. ; Grudzinska, M. ; Hadasch, D. ; Haeffner, S. ; Hahn, J. ; Hawkes, J. ; Heinzelmann, G. ; Henri, G. ; Hermann, G. ; Hervet, O. ; Hillert, A. ; Hinton, James Anthony ; Hofmann, W. ; Hofverberg, P. ; Hoischen, Clemens ; Holler, M. ; Horns, D. ; Ivascenko, A. ; Jacholkowska, A. ; Jamrozy, M. ; Janiak, M. ; Jankowsky, F. ; Jung-Richardt, I. ; Kastendieck, M. A. ; Katarzynski, K. ; Katz, U. ; Kerszberg, D. ; Khelifi, B. ; Kieffer, M. ; Klepser, S. ; Klochkov, D. ; Kluzniak, W. ; Kolitzus, D. ; Komin, Nu. ; Kosack, K. ; Krakau, S. ; Krayzel, F. ; Krueger, P. P. ; Laffon, H. ; Lamanna, G. ; Lau, J. ; Lefaucheur, J. ; Lefranc, V. ; Lemiere, A. ; Lemoine-Goumard, M. ; Lenain, J-P. ; Lohse, T. ; Lopatin, A. ; Lu, C-C. ; Lui, R. ; Marandon, V. ; Marcowith, Alexandre ; Mariaud, C. ; Marx, R. ; Maurin, G. ; Maxted, N. ; Mayer, M. ; Meintjes, P. J. ; Menzler, U. ; Meyer, M. ; Mitchell, A. M. W. ; Moderski, R. ; Mohamed, M. ; Mora, K. ; Moulin, Emmanuel ; Murach, T. ; de Naurois, M. ; Niemiec, J. ; Oakes, L. ; Odaka, H. ; Oettl, S. ; Ohm, S. ; Opitz, B. ; Ostrowski, M. ; Oya, I. ; Panter, M. ; Parsons, R. D. ; Arribas, M. Paz ; Pekeur, N. W. ; Pelletier, G. ; Petrucci, P-O. ; Peyaud, B. ; Pita, S. ; Poon, H. ; Prokoph, H. ; Puehlhofer, G. ; Punch, M. ; Quirrenbach, A. ; Raab, S. ; Reichardt, I. ; Reimer, A. ; Reimer, O. ; Renaud, M. ; de los Reyes, R. ; Rieger, F. ; Romoli, C. ; Rosier-Lees, S. ; Rowell, G. ; Rudak, B. ; Rulten, C. B. ; Sahakian, V. ; Salek, D. ; Sanchez, David M. ; Santangelo, Andrea ; Sasaki, M. ; Schlickeiser, R. ; Schuessler, F. ; Schulz, A. ; Schwanke, U. ; Schwemmer, S. ; Seyffert, A. S. ; Simoni, R. ; Sol, H. ; Spanier, F. ; Spengler, G. ; Spies, F. ; Stawarz, L. ; Steenkamp, R. ; Stegmann, Christian ; Stinzing, F. ; Stycz, K. ; Sushch, Iurii ; Tavernet, J-P. ; Tavernier, T. ; Taylor, A. M. ; Terrier, R. ; Tluczykont, M. ; Trichard, C. ; Tuffs, R. ; Valerius, K. ; van der Walt, J. ; van Eldik, C. ; van Soelen, B. ; Vasileiadis, G. ; Veh, J. ; Venter, C. ; Viana, A. ; Vincent, P. ; Vink, J. ; Voisin, F. ; Voelk, H. J. ; Vuillaume, T. ; Wagner, S. J. ; Wagner, P. ; Wagner, R. M. ; Weidinger, M. ; Weitzel, Q. ; White, R. ; Wierzcholska, A. ; Willmann, P. ; Woernlein, A. ; Wouters, D. ; Yang, R. ; Zabalza, V. ; Zaborov, D. ; Zacharias, M. ; Zdziarski, A. A. ; Zech, Alraune ; Zefi, F. ; Zywucka, N.
Galactic cosmic rays reach energies of at least a few petaelectronvolts (of the order of 1015 electronvolts). This implies that our Galaxy contains petaelectronvolt accelerators (‘PeVatrons’), but all proposed models of Galactic cosmic-ray accelerators encounter difficulties at exactly these energies. Dozens of Galactic accelerators capable of accelerating particles to energies of tens of teraelectronvolts (of the order of 1013 electronvolts) were inferred from recent γ-ray observations3. However, none of the currently known accelerators—not even the handful of shell-type supernova remnants commonly believed to supply most Galactic cosmic rays—has shown the characteristic tracers of petaelectronvolt particles, namely, power-law spectra of γ-rays extending without a cut-off or a spectral break to tens of teraelectronvolts4. Here we report deep γ-ray observations with arcminute angular resolution of the region surrounding the Galactic Centre, which show the expected tracer of the presence of petaelectronvolt protons within the central 10 parsecs of the Galaxy. We propose that the supermassive black hole Sagittarius A* is linked to this PeVatron. Sagittarius A* went through active phases in the past, as demonstrated by X-ray outbursts5and an outflow from the Galactic Centre6. Although its current rate of particle acceleration is not sufficient to provide a substantial contribution to Galactic cosmic rays, Sagittarius A* could have plausibly been more active over the last 106–107 years, and therefore should be considered as a viable alternative to supernova remnants as a source of petaelectronvolt Galactic cosmic rays.
Abdalla, Hassan E. ; Collaboration, H. E. S. S. ; Abramowski, A. ; Aharonian, Felix A. ; Benkhali, F. Ait ; Angüner, Ekrem Oǧuzhan ; Arakawa, M. ; Armand, C. ; Arrieta, M. ; Backes, M. ; Balzer, A. ; Barnard, M. ; Becherini, Y. ; Tjus, J. Becker ; Berge, D. ; Bernhard, S. ; Bernloehr, K. ; Blackwell, R. ; Bottcher, M. ; Boisson, C. ; Bolmont, J. ; Bonnefoy, S. ; Bordas, Pol ; Bregeon, J. ; Brun, F. ; Brun, P. ; Bryan, M. ; Buechele, M. ; Bulik, T. ; Capasso, M. ; Caroff, S. ; Carosi, A. ; Casanova, Sabrina ; Cerruti, M. ; Chakraborty, N. ; Chaves, R. C. G. ; Chen, A. ; Chevalier, J. ; Colafrancesco, S. ; Condon, B. ; Conrad, J. ; Davids, I. D. ; Decock, J. ; Deil, C. ; Devin, J. ; deWilt, P. ; Dirson, L. ; Djannati-Atai, A. ; Donath, A. ; Dyks, J. ; Edwards, T. ; Egberts, Kathrin ; Emery, G. ; Ernenwein, J. -P. ; Eschbach, S. ; Farnier, C. ; Fegan, S. ; Fernandes, M. V. ; Fiasson, A. ; Fontaine, G. ; Funk, S. ; Fuessling, M. ; Gabici, S. ; Gallant, Y. A. ; Garrigoux, T. ; Gate, F. ; Giavitto, G. ; Glawion, D. ; Glicenstein, J. F. ; Gottschall, D. ; Grondin, M. -H. ; Hahn, J. ; Haupt, M. ; Hawkes, J. ; Heinzelmann, G. ; Henri, G. ; Hermann, G. ; Hinton, J. A. ; Hofmann, W. ; Hoischen, Clemens ; Holch, T. L. ; Holler, M. ; Horns, D. ; Ivascenko, A. ; Iwasaki, H. ; Jacholkowska, A. ; Jamrozy, M. ; Jankowsky, D. ; Jankowsky, F. ; Jingo, M. ; Jouvin, L. ; Jung-Richardt, I. ; Kastendieck, M. A. ; Katarzynski, K. ; Katsuragawa, M. ; Katz, U. ; Kerszberg, D. ; Khangulyan, D. ; Khelifi, B. ; King, J. ; Klepser, S. ; Klochkov, D. ; Kluzniak, W. ; Komin, Nu. ; Kosack, K. ; Krakau, S. ; Kraus, M. ; Kruger, P. P. ; Laffon, H. ; Lamanna, G. ; Lau, J. ; Lefaucheur, J. ; Lemiere, A. ; Lemoine-Goumard, M. ; Lenain, J. -P. ; Leser, Eva ; Lohse, T. ; Lorentz, M. ; Liu, R. ; Lopez-Coto, R. ; Lypova, I. ; Malyshev, D. ; Marandon, V. ; Marcowith, Alexandre ; Mariaud, C. ; Marx, R. ; Maurin, G. ; Maxted, N. ; Mayer, M. ; Meintjes, P. J. ; Meyer, M. ; Mitchell, A. M. W. ; Moderski, R. ; Mohamed, M. ; Mohrmann, L. ; Mora, K. ; Moulin, Emmanuel ; Murach, T. ; Nakashima, S. ; de Naurois, M. ; Ndiyavala, H. ; Niederwanger, F. ; Niemiec, J. ; Oakes, L. ; Odaka, H. ; Ohm, S. ; Ostrowski, M. ; Oya, I. ; Padovani, M. ; Panter, M. ; Parsons, R. D. ; Pekeur, N. W. ; Pelletier, G. ; Perennes, C. ; Petrucci, P. -O. ; Peyaud, B. ; Piel, Q. ; Pita, S. ; Poireau, V. ; Prokhorov, D. A. ; Prokoph, H. ; Puehlhofer, G. ; Punch, M. ; Quirrenbach, A. ; Raab, S. ; Rauth, R. ; Reimer, A. ; Reimer, O. ; Renaud, M. ; de los Reyes, R. ; Rieger, F. ; Rinchiuso, L. ; Romoli, C. ; Rowell, G. ; Rudak, B. ; Rulten, C. B. ; Sahakian, V. ; Saito, S. ; Sanchez, D. A. ; Santangelo, Andrea ; Sasaki, M. ; Schlickeiser, R. ; Schussler, F. ; Schulz, A. ; Schwanke, U. ; Schwemmer, S. ; Seglar-Arroyo, M. ; Seyffert, A. S. ; Shafi, N. ; Shilon, I. ; Shiningayamwe, K. ; Simoni, R. ; Sol, H. ; Spanier, F. ; Spir-Jacob, M. ; Stawarz, L. ; Steenkamp, R. ; Stegmann, Christian ; Steppa, Constantin Beverly ; Sushch, I. ; Takahashi, T. ; Tavernet, J. -P. ; Tavernier, T. ; Taylor, A. M. ; Terrier, R. ; Tibaldo, L. ; Tiziani, D. ; Tluczykont, M. ; Trichard, C. ; Tsirou, M. ; Tsuji, N. ; Tuffs, R. ; Uchiyama, Y. ; van der Walt, D. J. ; van Eldik, C. ; van Rensburg, C. ; van Soelen, B. ; Vasileiadis, G. ; Veh, J. ; Venter, C. ; Viana, A. ; Vincent, P. ; Vink, J. ; Voisin, F. ; Voelk, H. J. ; Vuillaume, T. ; Wadiasingh, Z. ; Wagner, S. J. ; Wagner, P. ; Wagner, R. M. ; White, R. ; Wierzcholska, A. ; Willmann, P. ; Woernlein, A. ; Wouters, D. ; Yang, R. ; Zaborov, D. ; Zacharias, M. ; Zanin, R. ; Zdziarski, A. A. ; Zech, Alraune ; Zefi, F. ; Ziegler, A. ; Zorn, J. ; Zywucka, N.
Context. Recently, the high-energy (HE, 0.1-100 GeV) gamma-ray emission from the object LMC P3 in the Large Magellanic Cloud (LMC) has been discovered to be modulated with a 10.3-day period, making it the first extra-galactic gamma-ray binary. Aims. This work aims at the detection of very-high-energy (VHE, >100 GeV) gamma-ray emission and the search for modulation of the VHE signal with the orbital period of the binary system. Methods. LMC P3 has been observed with the High Energy Stereoscopic System (H.E.S.S.); the acceptance-corrected exposure time is 100 h. The data set has been folded with the known orbital period of the system in order to test for variability of the emission. Results. VHE gamma-ray emission is detected with a statistical significance of 6.4 sigma. The data clearly show variability which is phase-locked to the orbital period of the system. Periodicity cannot be deduced from the H.E.S.S. data set alone. The orbit-averaged luminosity in the 1-10 TeV energy range is (1.4 +/- 0.2) x 10(35) erg s(-1). A luminosity of (5 +/- 1) x 10(35) erg s(-1) is reached during 20% of the orbit. HE and VHE gamma-ray emissions are anti-correlated. LMC P3 is the most luminous gamma-ray binary known so far.
Aleksic, J. ; Ansoldi, S. ; Antonelli, L. A. ; Antoranz, P. ; Babic, A. ; Bangale, P. ; de Almeida, U. Barres ; Barrio, J. A. ; Gonzalez, J. Becerra ; Bednarek, W. ; Berger, K. ; Bernardini, E. ; Bilandli, A. ; Bianch, O. ; Bock, R. K. ; Bonnefoy, S. ; Bonnoli, G. ; Borracci, F. ; Bretz, T. ; Carmona, E. ; Carosi, A. ; Fidalgo, D. Carreto ; Colin, P. ; Colombo, E. ; Contreras, J. L. ; Cortina, J. ; Covino, S. ; Da Vela, P. ; Dazzi, F. ; De Angelis, A. ; De Caneva, G. ; De Lotto, B. ; Delgado Mendez, C. ; Doert, M. ; Dominguez, A. ; Prester, Dijana Dominis ; Dorner, D. ; Doro, M. ; Einecke, S. ; Eisenacher, D. ; Elsaesser, D. ; Farina, E. ; Ferenc, D. ; Fonseca, M. V. ; Font, L. ; Frantzen, K. ; Fruck, C. ; Garcia Lopez, R. J. ; Garczarczyki, M. ; Garrido Terrats, D. ; Gaug, M. ; Giavitto, G. ; Godinovic, N. ; Gonzalez Munoz, A. ; Gozzini, S. R. ; Hadamek, A. ; Hadasch, D. ; Herrero, A. ; Hildebrand, D. ; Hose, J. ; Hrupec, D. ; Idec, W. ; Kadenius, V. ; Kellermann, H. ; Knoetig, M. L. ; Krause, J. ; Kushida, J. ; La Barbera, A. ; Lelas, D. ; Lewandowska, N. ; Lindfors, E. ; Longo, F. ; Lombardi, S. ; Lopez, M. ; Lopez-Coto, R. ; Lopez-Oramas, A. ; Lorenz, E. ; Lozano, I. ; Makariev, M. ; Mallot, K. ; Maneva, G. ; Mankuzhiyil, N. ; Mannheim, K. ; Maraschi, L. ; Marcote, B. ; Mariotti, M. ; Martinez, M. ; Mazin, D. ; Menzel, U. ; Meucci, M. ; Miranda, J. M. ; Mirzoyan, R. ; Moralejo, A. ; Munar-Adrover, P. ; Nakajima, D. ; Niedzwiecki, A. ; Nilsson, K. ; Nowak, N. ; Orito, R. ; Overkemping, A. ; Paiano, S. ; Palatiello, M. ; Paneque, D. ; Paoletti, R. ; Paredes, J. M. ; Paredes-Fortuny, X. ; Partini, S. ; Persic, M. ; Prada, F. ; Moroni, P. G. Prada ; Prandini, E. ; Preziuso, S. ; Puljak, I. ; Reinthal, R. ; Rhode, W. ; Ribo, M. ; Rico, J. ; Garcia, J. Rodriguez ; Ruegamer, S. ; Saggion, A. ; Saito, K. ; Salvati, M. ; Satalecka, K. ; Scalzotto, V. ; Scapin, V. ; Schuliz, C. ; Schweizer, T. ; Shore, S. N. ; Sillanpaa, A. ; Sitarek, J. ; Snidaric, I. ; Sobczynska, D. ; Spanier, F. ; Stamatescu, V. ; Stamerra, A. ; Steinbring, T. ; Storz, J. ; Sun, S. ; Suric, T. ; Takalo, L. ; Tavecchio, F. ; Temnikov, P. ; Terzic, T. ; Tescaro, D. ; Teshima, M. ; Thaele, J. ; Tibolla, O. ; Torres, D. F. ; Toyama, T. ; Treves, A. ; Uellenbeck, M. ; Vogler, P. ; Wagner, R. M. ; Zandanel, F. ; Zanin, R. ; Archambault, S. ; Behera, B. ; Beilicke, M. ; Benbow, W. ; Bird, R. ; Buckley, J. H. ; Bugaev, V. ; Cerruti, M. ; Chen, X. ; Ciupik, L. ; Collins-Hughes, E. ; Cui, W. ; Dumm, J. ; Eisch, J. D. ; Falcone, A. ; Federici, S. ; Feng, Q. ; Finley, J. P. ; Fleischhack, H. ; Fortin, P. ; Fortson, L. ; Furniss, A. ; Griffin, S. ; Griffiths, S. T. ; Grube, J. ; Gyuk, G. ; Hanna, D. ; Holder, J. ; Hughes, G. ; Humensky, T. B. ; Johnson, C. A. ; Kaaret, P. ; Kertzman, M. ; Khassen, Y. ; Kieda, D. ; Krawczynski, H. ; Krennrich, F. ; Kumar, S. ; Lang, M. J. ; Maier, G. ; McArthur, S. ; Meagher, K. ; Moriarty, P. ; Mukherjee, R. ; Ong, R. A. ; Otte, A. N. ; Park, N. ; Pichel, A. ; Pohl, M. ; Popkow, A. ; Prokoph, H. ; Quinn, M. J. ; Ragan, K. ; Rajotte, J. ; Reynolds, P. T. ; Richards, G. T. ; Roache, E. ; Rovero, A. C. ; Sembroski, G. H. ; Shahinyan, K. ; Staszak, D. ; Telezhinsky, Igor O. ; Theiling, M. ; Tucci, J. V. ; Tyler, J. ; Varlotta, A. ; Wakely, S. P. ; Weekes, T. C. ; Weinstein, A. ; Welsing, R. ; Wilhelm, Alina ; Williams, D. A. ; Zitzer, B. ; Villata, M. ; Raiteri, C. ; Aller, H. D. ; Aller, M. F. ; Chen, W. P. ; Jordan, B. ; Koptelova, E. ; Kurtanidze, O. M. ; Lahteenmaki, A. ; McBreen, B. ; Larionov, V. M. ; Lin, C. S. ; Nikolashvili, M. G. ; Angelakis, E. ; Capalbi, M. ; Carraminana, A. ; Carrasco, L. ; Cassaro, P. ; Cesarini, A. ; Fuhrmann, L. ; Giroletti, M. ; Hovatta, T. ; Krichbaum, T. P. ; Krimm, H. A. ; Max-Moerbeck, W. ; Moody, J. W. ; Maccaferri, G. ; Mori, Y. ; Nestoras, I. ; Orlati, A. ; Pace, C. ; Pearson, R. ; Perri, M. ; Readhead, A. C. S. ; Richards, J. L. ; Sadun, A. C. ; Sakamoto, T. ; Tammi, J. ; Tornikoski, M. ; Yatsu, Y. ; Zook, A.
Aims. We perform an extensive characterization of the broadband emission of Mrk 421, as well as its temporal evolution, during the non-flaring (low) state. The high brightness and nearby location (z = 0.031) of Mrk 421 make it an excellent laboratory to study blazar emission. The goal is to learn about the physical processes responsible for the typical emission of Mrk 421, which might also be extended to other blazars that are located farther away and hence are more difficult to study.
Methods. We performed a 4.5-month multi-instrument campaign on Mrk 421 between January 2009 and June 2009, which included VLBA, F-GAMMA, GASP-WEBT, Swift, RXTE, Fermi-LAT, MAGIC, and Whipple, among other instruments and collaborations. This extensive radio to very-high-energy (VHE; E > 100 GeV) gamma-ray dataset provides excellent temporal and energy coverage, which allows detailed studies of the evolution of the broadband spectral energy distribution.
Results. Mrk421 was found in its typical (non-flaring) activity state, with a VHE flux of about half that of the Crab Nebula, yet the light curves show significant variability at all wavelengths, the highest variability being in the X-rays. We determined the power spectral densities (PSD) at most wavelengths and found that all PSDs can be described by power-laws without a break, and with indices consistent with pink/red-noise behavior. We observed a harder-when-brighter behavior in the X-ray spectra and measured a positive correlation between VHE and X-ray fluxes with zero time lag. Such characteristics have been reported many times during flaring activity, but here they are reported for the first time in the non-flaring state. We also observed an overall anti-correlation between optical /UV and X-rays extending over the duration of the campaign.
Conclusions. The harder-when-brighter behavior in the X-ray spectra and the measured positive X-ray/VHE correlation during the 2009 multiwavelength campaign suggests that the physical processes dominating the emission during non-flaring states have similarities with those occurring during flaring activity. In particular, this observation supports leptonic scenarios as being responsible for the emission of Mrk 421 during non-flaring activity. Such a temporally extended X-ray /VHE correlation is not driven by any single flaring event, and hence is difficult to explain within the standard hadronic scenarios. The highest variability is observed in the X-ray band, which, within the one-zone synchrotron self-Compton scenario, indicates that the electron energy distribution is most variable at the highest energies.
Abramowski, Attila ; Aharonian, Felix A. ; Benkhali, Faical Ait ; Akhperjanian, A. G. ; Uner, E. O. Ang ; Backes, Michael ; Balenderan, Shangkari ; Balzer, Arnim ; Barnacka, Anna ; Becherini, Yvonne ; Tjus, J. Becker ; Berge, David ; Bernhard, Sabrina ; Bernlöhr, K. ; Birsin, E. ; Biteau, Jonathan ; Boettcher, Markus ; Boisson, Catherine ; Bolmont, J. ; Bordas, Pol ; Bregeon, Johan ; Brun, Francois ; Brun, Pierre ; Bryan, Mark ; Bulik, Tomasz ; Carrigan, Svenja ; Casanova, Sabrina ; Chadwick, Paula M. ; Chakraborty, N. ; Chalme-Calvet, R. ; Chaves, Ryan C. G. ; Chretien, M. ; Colafrancesco, Sergio ; Cologna, Gabriele ; Conrad, Jan ; Couturier, C. ; Cui, Y. ; Dalton, M. ; Davids, I. D. ; Degrange, B. ; Deil, C. ; deWilt, P. ; Djannati-Ataï, A. ; Domainko, W. ; Donath, A. ; Dubus, G. ; Dutson, K. ; Dyks, J. ; Dyrda, M. ; Edwards, T. ; Egberts, Kathrin ; Eger, P. ; Espigat, P. ; Farnier, C. ; Fegan, S. ; Feinstein, F. ; Fernandes, M. V. ; Fernandez, D. ; Fiasson, A. ; Fontaine, G. ; Foerster, A. ; Fuessling, M. ; Gabici, S. ; Gajdus, M. ; Gallant, Y. A. ; Garrigoux, T. ; Giavitto, G. ; Giebels, B. ; Glicenstein, J. F. ; Gottschall, D. ; Grondin, M. -H. ; Grudzinska, M. ; Hadasch, D. ; Haeffner, S. ; Hahn, J. ; Harris, J. ; Heinzelmann, G. ; Henri, G. ; Hermann, G. ; Hervet, O. ; Hillert, A. ; Hinton, James Anthony ; Hofmann, W. ; Hofverberg, P. ; Holler, Markus ; Horns, D. ; Ivascenko, A. ; Jacholkowska, A. ; Jahn, C. ; Jamrozy, M. ; Janiak, M. ; Jankowsky, F. ; Jung-Richardt, I. ; Kastendieck, M. A. ; Katarzynski, K. ; Katz, U. ; Kaufmann, S. ; Khelifi, B. ; Kieffer, M. ; Klepser, S. ; Klochkov, D. ; Kluzniak, W. ; Kolitzus, D. ; Komin, Nu. ; Kosack, K. ; Krakau, S. ; Krayzel, F. ; Krueger, P. P. ; Laffon, H. ; Lamanna, G. ; Lau, J. ; Lefaucheur, J. ; Lefranc, V. ; Lemiere, A. ; Lemoine-Goumard, M. ; Lenain, J. -P. ; Lohse, T. ; Lopatin, A. ; Lu, C. -C. ; Marandon, V. ; Marcowith, Alexandre ; Marx, R. ; Maurin, G. ; Maxted, N. ; Mayer, M. ; McComb, T. J. L. ; Mehault, J. ; Meintjes, P. J. ; Menzler, U. ; Meyer, M. ; Mitchell, A. M. W. ; Moderski, R. ; Mohamed, M. ; Mora, K. ; Moulin, Emmanuel ; Murach, T. ; de Naurois, M. ; Niemiec, J. ; Nolan, S. J. ; Oakes, L. ; Odaka, H. ; Ohm, S. ; Opitz, B. ; Ostrowski, M. ; Oya, I. ; Panter, M. ; Parsons, R. D. ; Arribas, M. Paz ; Pekeur, N. W. ; Pelletier, G. ; Petrucci, P. -O. ; Peyaud, B. ; Pita, S. ; Poon, H. ; Puehlhofer, G. ; Punch, M. ; Quirrenbach, A. ; Raab, S. ; Reichardt, I. ; Reimer, A. ; Reimer, O. ; Renaud, M. ; Reyes, R. de Los ; Rieger, F. ; Romoli, C. ; Rosier-Lees, S. ; Rowell, G. ; Rudak, B. ; Rulten, C. B. ; Sahakian, V. ; Salek, D. ; Sanchez, David M. ; Santangelo, Andrea ; Schlickeiser, R. ; Schuessler, F. ; Schulz, A. ; Schwanke, U. ; Schwarzburg, S. ; Schwemmer, S. ; Sol, H. ; Spanier, F. ; Spengler, G. ; Spies, F. ; Stawarz, L. ; Steenkamp, R. ; Stegmann, Christian ; Stinzing, F. ; Stycz, K. ; Sushch, Iurii ; Tavernet, J. -P. ; Tavernier, T. ; Taylor, A. M. ; Terrier, R. ; Tluczykont, M. ; Trichard, C. ; Valerius, K. ; Van Eldik, C. ; van Soelen, B. ; Vasileiadis, G. ; Veh, J. ; Venter, C. ; Viana, A. ; Vincent, P. ; Vink, J. ; Voelk, H. J. ; Volpe, F. ; Vorster, M. ; Vuillaume, T. ; Wagner, S. J. ; Wagner, P. ; Wagner, R. M. ; Ward, M. ; Weidinger, M. ; Weitzel, Q. ; White, R. ; Wierzcholska, A. ; Willmann, P. ; Woernlein, A. ; Wouters, D. ; Yang, R. ; Zabalza, V. ; Zaborov, D. ; Zacharias, M. ; Zdziarski, A. A. ; Zech, Alraune ; Zechlin, H. -S. ; Fukui, Y. ; Sano, H. ; Fukuda, T. ; Yoshiike, S.
This Letter reports the discovery of a remarkably hard spectrum source, HESS J1641-463, by the High Energy Stereoscopic System (H.E.S.S.) in the very high energy (VHE) domain. HESS J1641-463 remained unnoticed by the usual analysis techniques due to confusion with the bright nearby source HESS J1640-465. It emerged at a significance level of 8.5 standard deviations after restricting the analysis to events with energies above 4 TeV. It shows a moderate flux level of phi(E > 1TeV) = (3.64 +/- 0.44(stat)+/- 0.73(sys)) x 10(-13) cm(-2) s(-1), corresponding to 1.8% of the Crab Nebula flux above the same energy, and a hard spectrum with a photon index of Gamma = 2.07 +/- 0.11(stat)+/- 0.20(sys). It is a point-like source, although an extension up to a Gaussian width of sigma = 3 arcmin cannot be discounted due to uncertainties in the H.E.S.S. point-spread function. The VHE gamma-ray flux of HESS J1641-463 is found to be constant over the observed period when checking time binnings from the year-by-year to the 28 minute exposure timescales. HESS J1641-463 is positionally coincident with the radio supernova remnant SNR G338.5+0.1. No X-ray candidate stands out as a clear association; however, Chandra and XMM-Newton data reveal some potential weak counterparts. Various VHE gamma-ray production scenarios are discussed. If the emission from HESS J1641-463 is produced by cosmic ray protons colliding with the ambient gas, then their spectrum must extend close to 1 PeV. This object may represent a source population contributing significantly to the galactic cosmic ray flux around the knee.