Search for dark matter annihilation signals from unidentified Fermi-LAT objects with H.E.S.S
Creators: name: Collaboration, H. E. S. S.
name: Abdallah, H.
name: Aharonian, F.
name: Benkhali, F. Ait
name: Angüner, E. O.
name: Arcaro, C.
name: Armand, C.
name: Armstrong, T.
name: Ashkar, H.
name: Backes, M.
name: Baghmanyan, V.
name: Martins, V. Barbosa
name: Barnacka, A.
name: Barnard, M.
name: Becherini, Y.
name: Berge, D.
name: Bernlöhr, K.
name: Bi, B.
name: Böttcher, M.
name: Boisson, C.
name: Bolmont, J.
name: de Lavergne, M. de Bony
name: Breuhaus, M.
name: Brose, R.
name: Brun, F.
name: Bulik, T.
name: Bylund, T.
name: Cangemi, F.
name: Caroff, S.
name: Casanova, S.
name: Chambery, P.
name: Chand, J. Catalano T.
name: Chen, A.
name: Cotter, G.
name: Curylo, M.
name: Dalgleish, H.
name: Mbarubucyeye, J. Damascene
name: Davids, I. D.
name: Davies, J.
name: Devin, J.
name: Djannati-Ataï, A.
name: Dmytriiev, A.
name: Donath, A.
name: Doroshenko, V.
name: Dreyer, L.
name: Plessis, L. Du
name: Duffy, C.
name: Egberts, K.
name: Einecke, S.
name: Emery, G.
name: Ernenwein, J. -P.
name: Feijen, K.
name: Fegan, S.
name: Fiasson, A.
name: de Clairfontaine, G. Fichet
name: Fontaine, G.
name: Funk, S.
name: Füßling, M.
name: Gabici, S.
name: Gallant, Y. A.
name: Giavitto, G.
name: Giunti, L.
name: Glawion, D.
name: Glicenstein, J. F.
name: Grondin, M. -H.
name: Hattingh, S.
name: Haupt, M.
name: Hermann, G.
name: Hinton, J. A.
name: Hofmann, W.
name: Hoischen, C.
name: Holch, T. L.
name: Holler, M.
name: Hörbe, M.
name: Horns, D.
name: Huang, Z.
name: Huber, D.
name: Jamrozy, M.
name: Jankowsky, D.
name: Jankowsky, F.
name: Joshi, V.
name: Jung-Richardt, I.
name: Kasai, E.
name: Katarzyński, K.
name: Katz, U.
name: Khangulyan, D.
name: Khèlifi, B.
name: Klepser, S.
name: Kluzniak, W.
name: Komin, Nu.
name: Konno, R.
name: Kosack, K.
name: Kostunin, D.
name: Kreter, M.
name: Mezek, G. Kukec
name: Kundu, A.
name: Lamanna, G.
name: Stum, S. Le
name: Lemière, A.
name: Lemoine-Goumard, M.
name: Lenain, J. -P.
name: Leuschner, F.
name: Levy, C.
name: Lohse, T.
name: Luashvili, A.
name: Lypova, I.
name: Mackey, J.
name: Majumdar, J.
name: Malyshev, D.
name: Malyshev, D.
name: Marandon, V.
name: Marchegiani, P.
name: Marcowith, A.
name: Mares, A.
name: Martì-Devesa, G.
name: Marx, R.
name: Maurin, G.
name: Meintjes, P. J.
name: Meyer, M.
name: Mitchell, A.
name: Moderski, R.
name: Mohrmann, L.
name: Montanari, A.
name: Moore, C.
name: Morris, P.
name: Moulin, E.
name: Muller, J.
name: Murach, T.
name: Nakashima, K.
name: Nayerhoda, A.
name: de Naurois, M.
name: Ndiyavala, H.
name: Niemiec, J.
name: Noel, A.
name: Oberholzer, L.
name: O'Brien, P.
name: Ohm, S.
name: Olivera-Nieto, L.
name: Wilhelmi, E. de Ona
name: Ostrowski, M.
name: Panter, M.
name: Panny, S.
name: Parsons, R. D.
name: Peron, G.
name: Pita, S.
name: Poireau, V.
name: Prokhorov, D. A.
name: Prokoph, H.
name: Pühlhofer, G.
name: Punch, M.
name: Quirrenbach, A.
name: Reichherzer, P.
name: Reimer, A.
name: Reimer, O.
name: Remy, Q.
name: Renaud, M.
name: Rieger, F.
name: Romoli, C.
name: Rowell, G.
name: Rudak, B.
name: Ricarte, H. Rueda
name: Ruiz-Velasco, E.
name: Sahakian, V.
name: Sailer, S.
name: Salzmann, H.
name: Sanchez, D. A.
name: Santangelo, A.
name: Sasaki, M.
name: Schüssler, F.
name: Schutte, H. M.
name: Schwanke, U.
name: Senniappan, M.
name: Seyffert, A. S.
name: Shapopi, J. N. S.
name: Shiningayamwe, K.
name: Simoni, R.
name: Sinha, A.
name: Sol, H.
name: Spackman, H.
name: Specovius, A.
name: Spencer, S.
name: Spir-Jacob, M.
name: Stawarz, L.
name: Sun, L.
name: Steenkamp, R.
name: Stegmann, C.
name: Steinmassl, S.
name: Steppa, C.
name: Takahashi, T.
name: Tanaka, T.
name: Tavernier, T.
name: Taylor, A. M.
name: Terrier, R.
name: Morgan, C. Thorpe
name: Thiersen, J. H. E.
name: Tluczykont, M.
name: Tomankova, L.
name: Trichard, C.
name: Tsirou, M.
name: Tsuji, M.
name: Tuffs, R.
name: Uchiyama, Y.
name: van der Walt, D. J.
name: van Eldik, C.
name: van Rensburg, C.
name: van Soelen, B.
name: Vasileiadis, G.
name: Veh, J.
name: Venter, C.
name: Viana, A.
name: Vincent, P.
name: Vink, J.
name: Völk, H. J.
name: Wagner, S. J.
name: Werner, F.
name: White, R.
name: Wierzcholska, A.
name: Wong, Yu Wun
name: Yassin, H.
name: Yusafzai, A.
name: Zacharias, M.
name: Zanin, R.
name: Zargaryan, D.
name: Zdziarski, A. A.
name: Zech, A.
name: Zhu, S.
name: Zmija, A.
name: Zorn, J.
name: Zouari, S.
name: Zywucka, N.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: Cosmological $N$-body simulations show that Milky Way-sized galaxies harbor a population of unmerged dark matter subhalos. These subhalos could shine in gamma-rays and be eventually detected in gamma-ray surveys as unidentified sources. We performed a thorough selection among unidentified Fermi-LAT Objects (UFOs) to identify them as possible TeV-scale dark matter subhalo candidates. We search for very-high-energy (E $\gtrsim$ 100 GeV) gamma-ray emissions using H.E.S.S. observations towards four selected UFOs. Since no significant very-high-energy gamma-ray emission is detected in any dataset of the four observed UFOs nor in the combined UFO dataset, strong constraints are derived on the product of the velocity-weighted annihilation cross section $\langle σv \rangle$ by the $J$-factor for the dark matter models. The 95% C.L. observed upper limits derived from combined H.E.S.S. observations reach $\langle σv \rangle J$ values of 3.7$\times$10$^{-5}$ and 8.1$\times$10$^{-6}$ GeV$^2$cm$^{-2}$s$^{-1}$ in the $W^+W^-$ and $τ^+τ^-$ channels, respectively, for a 1 TeV dark matter mass. Focusing on thermal WIMPs, the H.E.S.S. constraints restrict the $J$-factors to lie in the range 6.1$\times$10$^{19}$ - 2.0$\times$10$^{21}$ GeV$^2$cm$^{-5}$, and the masses to lie between 0.2 and 6 TeV in the $W^+W^-$ channel. For the $τ^+τ^-$ channel, the $J$-factors lie in the range 7.0$\times$10$^{19}$ - 7.1$\times$10$^{20}$ GeV$^2$cm$^{-5}$ and the masses lie between 0.2 and 0.5 TeV. Assuming model-dependent predictions from cosmological N-body simulations on the $J$-factor distribution for Milky Way-sized galaxies, the dark matter models with masses greater than 0.3 TeV for the UFO emissions can be ruled out at high confidence level.
description: 11 pages, 7 figures, matches accepted version in The Astrophysical Journal