학술논문
Constraining the cosmic-ray pressure in the inner Virgo Cluster using H.E.S.S. observations of M 87
Document Type
Working Paper
Author
Collaboration, H. E. S. S.; Aharonian, F.; Benkhali, F. Ait; Arcaro, C.; Aschersleben, J.; Backes, M.; Martins, V. Barbosa; 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.; Mbarubucyeye, J. Damascene; Djannati-Ataï, A.; Egberts, K.; Ernenwein, J. -P.; de Clairfontaine, G. Fichet; 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.; Stum, S. Le; 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.; Noel, A. Priyana; O'Brien, P.; Ohm, S.; Olivera-Nieto, L.; Wilhelmi, E. de Ona; Panny, S.; Panter, M.; Parsons, R. D.; Peron, G.; Pita, S.; Prokhorov, D. A.; Prokoph, H.; Pühlhofer, G.; Quirrenbach, A.; Reichherzer, P.; Reimer, A.; Reimer, O.; Renaud, M.; Rieger, F.; Rowell, G.; Rudak, B.; Velasco, E. Ruiz; 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, Yu Wun; Zacharias, M.; Zargaryan, D.; Zdziarski, A. A.; Zech, A.; Zouari, S.; Żywucka, N.
Source
A&A 675, A138 (2023)
Subject
Language
Abstract
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.
Comment: 15 pages, 7 figures. Accepted for publication in A&A. Corresponding authors: Victor Barbosa Martins, Stefan Ohm, Cornelia Arcaro, Natalia \.Zywucka, Mathieu de Naurois
Comment: 15 pages, 7 figures. Accepted for publication in A&A. Corresponding authors: Victor Barbosa Martins, Stefan Ohm, Cornelia Arcaro, Natalia \.Zywucka, Mathieu de Naurois