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arXiv · 1901.03982

MAGIC and Fermi-LAT gamma-ray results on unassociated HAWC sources

Abstract

The HAWC Collaboration released the 2HWC catalog of TeV sources, in which 19 show no association with any known high-energy (HE; E > 10 GeV) or very-high-energy (VHE; E > 300 GeV) sources. This catalog motivated follow-up studies by both the MAGIC and Fermi-LAT observatories with the aim of investigating gamma-ray emission over a broad energy band. In this paper, we report the results from the first joint work between HAWC, MAGIC and Fermi-LAT on three unassociated HAWC sources: 2HWC J2006+341, 2HWC J1907+084* and 2HWC J1852+013*. Although no significant detection was found in the HE and VHE regimes, this investigation shows that a minimum 1 degree extension (at 95% confidence level) and harder spectrum in the GeV than the one extrapolated from HAWC results are required in the case of 2HWC J1852+013*, while a simply minimum extension of 0.16 degrees (at 95% confidence level) can already explain the scenario proposed by HAWC for the remaining sources. Moreover, the hypothesis that these sources are pulsar wind nebulae is also investigated in detail.

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M. L. Ahnen, S. Ansoldi, L. A. Antonelli, C. Arcaro, D. Baack, A. Babić, B. Banerjee, P. Bangale, U. Barres de Almeida, J. A. Barrio, J. Becerra González, W. Bednarek, E. Bernardini, R. Ch. Berse, A. Berti, W. Bhattacharyya, A. Biland, O. Blanch, G. Bonnoli, R. Carosi, A. Carosi, G. Ceribella, A. Chatterjee, S. M. Colak, P. Colin, E. Colombo, J. L. Contreras, J. Cortina, S. Covino, P. Cumani, P. Da Vela, F. Dazzi, A. De Angelis, B. De Lotto, M. Delfino, J. Delgado, F. Di Pierro, A. Domínguez, D. Dominis Prester, D. Dorner, M. Doro, S. Einecke, D. Elsaesser, V. Fallah Ramazani, A. Fernández-Barral, D. Fidalgo, M. V. Fonseca, L. Font, C. Fruck, D. Galindo, R. J. García López, M. Garczarczyk, M. Gaug, P. Giammaria, N. Godinović, D. Gora, D. Guberman, D. Hadasch, A. Hahn, T. Hassan, M. Hayashida, J. Herrera, J. Hose, D. Hrupec, K. Ishio, Y. Konno, H. Kubo, J. Kushida, D. Kuveždić, D. Lelas, E. Lindfors, S. Lombardi, F. Longo, M. López, C. Maggio, P. Majumdar, M. Makariev, G. Maneva, M. Manganaro, K. Mannheim, L. Maraschi, M. Mariotti, M. Martínez, S. Masuda, D. Mazin, K. Mielke, M. Minev, J. M. Miranda, R. Mirzoyan, A. Moralejo, V. Moreno, E. Moretti, T. Nagayoshi, V. Neustroev, A. Niedzwiecki, M. Nievas Rosillo, C. Nigro, K. Nilsson, D. Ninci, K. Nishijima. 2019-01-13. MAGIC and Fermi-LAT gamma-ray results on unassociated HAWC sources. https://doi.org/10.1093/mnras%2Fstz089

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