Autor: |
R. Zanin, A. Saggion, Nikola Godinovic, Daniel Nieto, Adrian Biland, Gianluca Giavitto, A. González Muñoz, Hanna Kellermann, Takashi Saito, J. M. Paredes, Antonio Stamerra, D. Dominis Prester, P. G. Prada Moroni, D. Häfner, O. Tibolla, T. Jogler, R. Reinthal, Nina Nowak, L. Maraschi, Elina Lindfors, R. J. García López, J. Rico, Dominik Elsaesser, Francesco Dazzi, M. V. Fonseca, Reiko Orito, U. Barres de Almeida, Aaron Dominguez, Daniel Mazin, E. Leonardo, Silvia Pardo, J. Storz, Nijil Mankuzhiyil, Giacomo Bonnoli, Christian Fruck, Damir Lelas, P. Munar-Adrover, M. A. Perez-Torres, Victor Stamatescu, Francisco Prada, M. I. Martínez, M. Asensio, A. Cañellas, J. Krause, A. Diago Ortega, Robert Wagner, Massimo Persic, B. De Lotto, Dorota Sobczyńska, G. De Caneva, Louis Antonelli, B. Steinke, Victor Zabalza, Denis Bastieri, Q. Weitzel, C. Delgado Mendez, S. R. Gozzini, Stefano Covino, T. Krähenbühl, Tihomir Surić, Tomislav Terzić, R. Mirzoyan, Riccardo Paoletti, D. Eisenacher, Daniela Dorner, S. Rügamer, N. Strah, E. Colombo, Ralph Bock, E. Carmona, Markus Garczarczyk, Konstancja Satalecka, Michele Doro, E. Prandini, K. Berger, S. Klepser, Juan Abel Barrio, Dario Hrupec, M. A. Lopez, L. O. Takalo, Jelena Aleksić, D. Tescaro, Masahiro Teshima, A. Boller, L. Cossio, A. Niedzwiecki, D. Borla Tridon, Aldo Treves, M. Salvati, Mosè Mariotti, Julian Sitarek, Marc Ribó, Elisa Bernardini, David Paneque, M. Uellenbeck, A. Sillanpää, Diego F. Torres, J. Hose, Daniela Hadasch, B. Huber, Artemio Herrero, V. Kadenius, Felix Spanier, A. De Angelis, Abelardo Moralejo, S. Paiano, Ignasi Reichardt, Saverio Lombardi, Ivica Puljak, Pierre Colin, P. Temnikov, Hajime Takami, Daniel Ferenc, Karl Mannheim, Fabio Zandanel, P. Da Vela, Shan Sun, J. Pochon, G. Maneva, Natalia Lewandowska, F. Jankowski, I. Puerto Gimenez, A. La Barbera, T. Schweizer, C. Schultz, V. Scapin, D. Hildebrand, J. Becerra González, Mario Meucci, P. Antoranz, S. Partini, Martin Makariev, Oscar Blanch, M. Doert, Michael Backes, A. López-Oramas, Wlodek Bednarek, Alessandro Carosi, Ruben Lopez-Coto, Thomas Bretz, D. Garrido, S. N. Shore, M. Pilia, Jose Miguel Miranda, Wolfgang Rhode, E. De Cea del Pozo, V. Scalzotto, J. Moldón, Fabrizio Tavecchio, Kari Nilsson, Ll. Font, I. Snidaric, S. Spiro, E. Lorenz, Jose Luis Contreras, K. Saito, Juan Cortina, Patrick Vogler, E. A. Alvarez |
Rok vydání: |
2012 |
Předmět: |
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Zdroj: |
E-Prints Complutense: Archivo Institucional de la UCM Universidad Complutense de Madrid A&A Astronomy and astrophysics 541, 13 (2012). doi:10.1051/0004-6361/201218846 DESY Publication Database E-Prints Complutense SNSF P3 Database Open Access Repository arXiv.org e-Print Archive Full-text Institutional Repository of the Ruđer Bošković Institute E-Prints Complutense. Archivo Institucional de la UCM instname Astronomy and Astrophysics Dipòsit Digital de la UB Universidad de Barcelona |
DOI: |
10.48550/arxiv.1201.4074 |
Popis: |
The W51 complex hosts the supernova remnant W51C which is known to interact with the molecular clouds in the star forming region W51B. In addition, a possible pulsar wind nebula CXO J192318.5+140305 was found likely associated with the supernova remnant. Gamma-ray emission from this region was discovered by Fermi/LAT (between 0.2 and 50 GeV) and H.E.S.S. (>1 TeV). The spatial distribution of the events could not be used to pinpoint the location of the emission among the pulsar wind nebula, the supernova remnant shell and/or the molecular cloud. However, the modeling of the spectral energy distribution presented by the Fermi/LAT collaboration suggests a hadronic emission mechanism. We performed observations of the W51 complex with the MAGIC telescopes for more than 50 hours. The good angular resolution in the medium (few hundred GeV) to high (above 1 TeV) energies allow us to perform morphological studies. We detect an extended emission of very-high-energy gamma rays, with a significance of 11 standard deviations. We extend the spectrum from the highest Fermi/LAT energies to \sim 5 TeV and find that it follows a single power law with an index of 2.58 \pm 0.07stat \pm 0.22syst . The main part of the emission coincides with the shocked cloud region, while we find a feature extending towards the pulsar wind nebula. The possible contribution of the pulsar wind nebula, assuming a point-like source, shows no dependence on energy and it is about 20% of the overall emission. The broad band spectral energy distribution can be explained with a hadronic model that implies proton acceleration above 100 TeV. This result, together with the morphology of the source, tentatively suggests that we observe ongoing acceleration of ions in the interaction zone between supernova remnant and cloud. These results shed light on the long-standing problem of the origin of galactic cosmic rays. 11 pages, 7 figures, accepted by A&A, corresponding authors: J. Krause, I Reichardt, E. Carmona |
Databáze: |
OpenAIRE |
Externí odkaz: |
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