Observation of gamma rays up to 320 TeV from the middle-aged TeV pulsar wind nebula HESS J1849$-$000
Creators: name: Amenomori, M.
name: Asano, S.
name: Bao, Y. W.
name: Bi, X. J.
name: Chen, D.
name: Chen, T. L.
name: Chen, W. Y.
name: Chen, Xu
name: Chen, Y.
name: Cirennima
name: Cui, S. W.
name: Danzengluobu
name: Ding, L. K.
name: Fang, J. H.
name: Fang, K.
name: Feng, C. F.
name: Feng, Zhaoyang
name: Feng, Z. Y.
name: Gao, Qi
name: Gomi, A.
name: Gou, Q. B.
name: Guo, Y. Q.
name: Guo, Y. Y.
name: Hayashi, Y.
name: He, H. H.
name: He, Z. T.
name: Hibino, K.
name: Hotta, N.
name: Hu, Haibing
name: Hu, H. B.
name: Hu, K. Y.
name: Huang, J.
name: Jia, H. Y.
name: Jiang, L.
name: Jiang, P.
name: Jin, H. B.
name: Kasahara, K.
name: Katayose, Y.
name: Kato, C.
name: Kato, S.
name: Kawahara, I.
name: Kawashima, T.
name: Kawata, K.
name: Kozai, M.
name: Kurashige, D.
name: Labaciren
name: Le, G. M.
name: Li, A. F.
name: Li, H. J.
name: Li, W. J.
name: Li, Y.
name: Lin, Y. H.
name: Liu, B.
name: Liu, C.
name: Liu, J. S.
name: Liu, L. Y.
name: Liu, M. Y.
name: Liu, W.
name: Lu, H.
name: Meng, X. R.
name: Meng, Y.
name: Munakata, K.
name: Nagaya, K.
name: Nakamura, Y.
name: Nakazawa, Y.
name: Nanjo, H.
name: Ning, C. C.
name: Nishizawa, M.
name: Noguchi, R.
name: Ohnishi, M.
name: Okukawa, S.
name: Ozawa, S.
name: Qian, X.
name: Qian, X. L.
name: Qu, X. B.
name: Saito, T.
name: Sakakibara, Y.
name: Sakata, M.
name: Sako, T.
name: Sako, T. K.
name: Sasaki, T.
name: Shao, J.
name: Shibata, M.
name: Shiomi, A.
name: Sugimoto, H.
name: Takano, W.
name: Takita, M.
name: Tan, Y. H.
name: Tateyama, N.
name: Torii, S.
name: Tsuchiya, H.
name: Udo, S.
name: Wang, H.
name: Wang, S. F.
name: Wang, Y. P.
name: Wangdui
name: Wu, H. R.
name: Wu, Q.
name: Xu, J. L.
name: Xue, L.
name: Yang, Z.
name: Yao, Y. Q.
name: Yin, J.
name: Yokoe, Y.
name: Yu, Y. L.
name: Yuan, A. F.
name: Zhai, L. M.
name: Zhang, H. M.
name: Zhang, J. L.
name: Zhang, X.
name: Zhang, X. Y.
name: Zhang, Y.
name: Zhang, Yi
name: Zhang, Ying
name: Zhao, S. P.
name: Zhaxisangzhu
name: Zhou, X. X.
name: Zou, Y. H.
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: Gamma rays from HESS J1849$-$000, a middle-aged TeV pulsar wind nebula (PWN), are observed by the Tibet air shower array and the muon detector array. The detection significance of gamma rays reaches $4.0\, σ$ and $4.4\, σ$ levels above 25 TeV and 100 TeV, respectively, in units of Gaussian standard deviation $σ$. The energy spectrum measured between $40\, {\rm TeV} &lt; E &lt; 320\, {\rm TeV}$ for the first time is described with a simple power-law function of ${\rm d}N/{\rm d}E = (2.86 \pm 1.44) \times 10^{-16}(E/40\, {\rm TeV})^{-2.24 \pm 0.41}\, {\rm TeV}^{-1}\, {\rm cm}^{-2}\, {\rm s}^{-1}$. The gamma-ray energy spectrum from the sub-TeV ($E &lt; 1\, {\rm TeV}$) to sub-PeV ($100\, {\rm TeV} &lt; E &lt; 1\, {\rm PeV}$) ranges including the results of previous studies can be modeled with the leptonic scenario, inverse Compton scattering by high-energy electrons accelerated by the PWN of PSR J1849$-$0001. On the other hand, the gamma-ray energy spectrum can also be modeled with the hadronic scenario in which gamma rays are generated from the decay of neutral pions produced by collisions between accelerated cosmic-ray protons and the ambient molecular cloud found in the gamma-ray emitting region. The cutoff energy of cosmic-ray protons $E_{\rm p\, cut}$, cut is estimated at ${\rm log}_{10}(E_{\rm p,\, cut}/{\rm TeV}) = 3.73^{+2.98}_{-0.66}$, suggesting that protons are accelerated up to the PeV energy range. Our study thus proposes that HESS J1849$-$000 should be further investigated as a new candidate for a Galactic PeV cosmic-ray accelerator, PeVatron.
description: 10 pages, 2 figures, Accepted for publication from the Astrophysical Journal