Curvature in the very-high energy gamma-ray spectrum of M 87

Aharonian F, Ait Benkhali F, Aschersleben J, Ashkar H, Backes M, Martins VB, Batzofin R, Becherini Y, Berge D, Bernlohr K, Bottcher M, Boisson C, Bolmont J, De Lavergne MDB, Bradascio F, Brose R, Brun F, Bruno B, Bulik T, Burger-Scheidlin C, Bylund T, Casanova S, Cecil R, Celic J, Cerruti M, Chand T, Chandra S, Chen A, Chibueze J, Chibueze O, Collins T, Cotter G, Mbarubucyeye JD, Djannati-Atai A, Djuvsland J, Dmytriiev A, Egberts K, Einecke S, Fegan S, Fontaine G, Funk S, Gabici S, Glicenstein JF, Glombitza J, Grolleron G, Haerer L, Hofmann W, Holch TL, Holler M, Horns D, Jamrozy M, Jankowsky F, Joshi V, Jung-Richardt I, Kasai E, Katarzyński K, Khatoon R, Khelifi B, Kluźniak W, Komin N, Kosack K, Kostunin D, Kundu A, Guedes Lang R, Le Stum S, Leitl F, Lemiere A, Lemoine-Goumard M, Lenain JP, Lypova I, Luashvili A, MacKey J, Malyshev D, Marti-Devesa G, Marx R, Mehta A, Meyer M, Mitchell A, Moderski R, Moghadam MO, Mohrmann L, Montanari A, Moulin E, Murach T, De Naurois M, Niemiec J, Ohm S, Olivera-Nieto L, Wilhelmi EDO, Panny S, Panter M, Parsons RD, Pensec U, Pita S, Puhlhofer G, Punch M, Quirrenbach A, Regeard M, Reimer A, Reimer O, Ren H, Reville B, Rieger F, Rudak B, Ruiz-Velasco E, Sahakian V, Salzmann H, Santangelo A, Sasaki M, Schussler F, Schutte HM, Shapopi JN, Sol H, Spencer S, Stawarz L, Steenkamp R, Steinmassl S, Steppa C, Streil K, Takahashi T, Tanaka T, Taylor AM, Terrier R, Tsirou M, van Eldik C, Venter C, Vink J, Wach T, Wagner SJ, Wierzcholska A, Zacharias M, Zdziarski AA, Zech A, Zilberman P, Zywucka N (2024)

Publication Type: Journal article

Publication year: 2024

Journal

Book Volume: 685

Article Number: A96

DOI: 10.1051/0004-6361/202348913

Abstract

The radio galaxy M 87 is a variable very-high energy (VHE) gamma-ray source, exhibiting three major flares, which were reported in 2005, 2008, and 2010. Despite extensive studies, the origin of the VHE gamma-ray emission is not yet fully understood. In this study, we investigate the VHE gamma-ray spectrum of M 87 during states of high gamma-ray activity, utilizing 20.2 h of H.E.S.S. observations. Our findings indicate a preference for a curved spectrum, characterized by a log-parabola model with extra-galactic background light (EBL) model above 0.3 TeV at the 4σ level, compared to a power-law spectrum with EBL. We investigate the degeneracy between the absorption feature and the EBL normalization and derive upper limits on EBL models that are mainly sensitive in the wavelength range of 12.4 μm-40 μm.

Authors with CRIS profile

Involved external institutions

Noordwes-Universiteit / North-West University South Africa (ZA) Universität Hamburg (UHH) Germany (DE) Laboratoire Univers et Théories (LUTH) / Laboratory of the Universe and Theories France (FR) University of Warsaw / Uniwersytet Warszawski Poland (PL) Institute of Nuclear Physics Polish Academy of Sciences / Instytut Fizyki Jądrowej im. Henryka Niewodniczańskiego Polskiej Akademii Nauk Poland (PL) Ruprecht-Karls-Universität Heidelberg Germany (DE) Université Paris-Saclay France (FR) University of the Witwatersrand (WITS) South Africa (ZA) Deutsches Elektronen-Synchrotron DESY Germany (DE) Max-Planck-Institut für Kernphysik (MPIK) / Max Planck Institute for Nuclear Physics Germany (DE) University of Namibia (UNAM) Namibia (NA) Universität Potsdam Germany (DE) Université Paris-Sud France (FR) Nicolaus Copernicus University (NCU) / Uniwersytet Mikołaja Kopernika w Toruniu (UMK) Poland (PL) Sorbonne Université France (FR) Eberhard Karls Universität Tübingen Germany (DE) Dublin Institute for Advanced Studies (DIAS) Ireland (IE) Leopold-Franzens-Universität Innsbruck / University of Innsbruck Austria (AT) Laboratoire Leprince-Ringuet (LLR) France (FR) Konan University / 甲南大学 Japan (JP) Humboldt-Universität zu Berlin Germany (DE) Institute of Research into the Fundamental Laws of the Universe / Institut de recherche sur les lois fondamentales de l'univers (IRFU) France (FR) Yerevan Physics Institute (YerPhI) / Երևանի Ֆիզիկայի Ինստիտուտ Armenia (AM) Jagiellonian University / Uniwersytet Jagielloński (UJ) Poland (PL) Nicolaus Copernicus Astronomical Centre of the Polish Academy of Sciences Poland (PL) University of Tokyo Japan (JP) University of Groningen / Rijksuniversiteit Groningen Netherlands (NL) Université de Bordeaux France (FR) University of Amsterdam Netherlands (NL) University of Oxford United Kingdom (GB) University of Adelaide Australia (AU) Institut national de physique nucléaire et de physique des particules (IN2P3) France (FR)

How to cite

APA:

Aharonian, F., Ait Benkhali, F., Aschersleben, J., Ashkar, H., Backes, M., Martins, V.B.,... Zywucka, N. (2024). Curvature in the very-high energy gamma-ray spectrum of M 87. Astronomy & Astrophysics, 685. https://doi.org/10.1051/0004-6361/202348913

MLA:

Aharonian, F., et al. "Curvature in the very-high energy gamma-ray spectrum of M 87." Astronomy & Astrophysics 685 (2024).

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