1. Observation of gamma rays up to 320 TeV from the middle-aged TeV pulsar wind nebula HESS J1849$-$000
- Author
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Amenomori, M., Asano, S., Bao, Y. W., Bi, X. J., Chen, D., Chen, T. L., Chen, W. Y., Chen, Xu, Chen, Y., Cirennima, Cui, S. W., Danzengluobu, Ding, L. K., Fang, J. H., Fang, K., Feng, C. F., Feng, Zhaoyang, Feng, Z. Y., Gao, Qi, Gomi, A., Gou, Q. B., Guo, Y. Q., Guo, Y. Y., Hayashi, Y., He, H. H., He, Z. T., Hibino, K., Hotta, N., Hu, Haibing, Hu, H. B., Hu, K. Y., Huang, J., Jia, H. Y., Jiang, L., Jiang, P., Jin, H. B., Kasahara, K., Katayose, Y., Kato, C., Kato, S., Kawahara, I., Kawashima, T., Kawata, K., Kozai, M., Kurashige, D., Labaciren, Le, G. M., Li, A. F., Li, H. J., Li, W. J., Li, Y., Lin, Y. H., Liu, B., Liu, C., Liu, J. S., Liu, L. Y., Liu, M. Y., Liu, W., Lu, H., Meng, X. R., Meng, Y., Munakata, K., Nagaya, K., Nakamura, Y., Nakazawa, Y., Nanjo, H., Ning, C. C., Nishizawa, M., Noguchi, R., Ohnishi, M., Okukawa, S., Ozawa, S., Qian, X., Qian, X. L., Qu, X. B., Saito, T., Sakakibara, Y., Sakata, M., Sako, T., Sako, T. K., Sasaki, T., Shao, J., Shibata, M., Shiomi, A., Sugimoto, H., Takano, W., Takita, M., Tan, Y. H., Tateyama, N., Torii, S., Tsuchiya, H., Udo, S., Wang, H., Wang, S. F., Wang, Y. P., Wangdui, Wu, H. R., Wu, Q., Xu, J. L., Xue, L., Yang, Z., Yao, Y. Q., Yin, J., Yokoe, Y., Yu, Y. L., Yuan, A. F., Zhai, L. M., Zhang, H. M., Zhang, J. L., Zhang, X., Zhang, X. Y., Zhang, Y., Zhang, Yi, Zhang, Ying, Zhao, S. P., Zhaxisangzhu, Zhou, X. X., and Zou, Y. H.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
Gamma rays from HESS J1849$-$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 $4.0\, \sigma$ and $4.4\, \sigma$ levels above 25 TeV and 100 TeV, respectively, in units of Gaussian standard deviation $\sigma$. The energy spectrum measured between $40\, {\rm TeV} < E < 320\, {\rm TeV}$ 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 ($E < 1\, {\rm TeV}$) to sub-PeV ($100\, {\rm TeV} < E < 1\, {\rm PeV}$) 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., Comment: 10 pages, 2 figures, Accepted for publication from the Astrophysical Journal
- Published
- 2023
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