Discovery of oscillations above 200 keV in a black hole X-ray binary with Insight-HXMT
Creators: name: Ma, Xiang
name: Tao, Lian
name: Zhang, Shuang-Nan
name: Zhang, Liang
name: Bu, Qing-Cui
name: Ge, Ming-Yu
name: Chen, Yu-Peng
name: Qu, Jin-Lu
name: Zhang, Shu
name: Lu, Fang-Jun
name: Song, Li-Ming
name: Yang, Yi-Jung
name: Yuan, Feng
name: Cai, Ce
name: Cao, Xue-Lei
name: Chang, Zhi
name: Chen, Gang
name: Chen, Li
name: Chen, Tian-Xiang
name: Chen, Yi-Bao
name: Chen, Yong
name: Cui, Wei
name: Cui, Wei-Wei
name: Deng, Jing-Kang
name: Dong, Yong-Wei
name: Du, Yuan-Yuan
name: Fu, Min-Xue
name: Gao, Guan-Hua
name: Gao, He
name: Gao, Min
name: Gu, Yu-Dong
name: Guan, Ju
name: Guo, Cheng-Cheng
name: Han, Da-Wei
name: Huang, Yue
name: Huo, Jia
name: Ji, Long
name: Jia, Shu-Mei
name: Jiang, Lu-Hua
name: Jiang, Wei-Chun
name: Jin, Jing
name: Jin, Yong-Jie
name: Kong, Ling-Da
name: Li, Bing
name: Li, Cheng-Kui
name: Li, Gang
name: Li, Mao-Shun
name: Li, Ti-Pei
name: Li, Wei
name: Li, Xian
name: Li, Xiao-Bo
name: Li, Xu-Fang
name: Li, Yan-Guo
name: Li, Zheng-Wei
name: Liang, Xiao-Hua
name: Liao, Jin-Yuan
name: Liu, Bai-Sheng
name: Liu, Cong-Zhan
name: Liu, Guo-Qing
name: Liu, Hong-Wei
name: Liu, Xiao-Jing
name: Liu, Yi-Nong
name: Lu, Bo
name: Lu, Xue-Feng
name: Luo, Qi
name: Luo, Tao
name: Meng, Bin
name: Nang, Yi
name: Nie, Jian-Yin
name: Ou, Ge
name: Sai, Na
name: Shang, Ren-Cheng
name: Song, Xin-Ying
name: Sun, Liang
name: Tan, Ying
name: Tuo, Yuo-Li
name: Wang, Chen
name: Wang, Guo-Feng
name: Wang, Juan
name: Wang, Ling-Jun
name: Wang, Wen-Shuai
name: Wang, Yu-Sa
name: Wen, Xiang-Yang
name: Wu, Bai-Yang
name: Wu, Bo-Bing
name: Wu, Mei
name: Xiao, Guang-Cheng
name: Xiao, Shuo
name: Xie, Fu-Guo
name: Xiong, Shao-Lin
name: Xu, He
name: Xu, Yu-Peng
name: Yang, Jia-Wei
name: Yang, Sheng
name: Yang, Yan-Ji
name: Yi, Qi-Bin
name: Yin, Qian-Qing
name: You, Yuan
name: Zhang, Ai-Mei
name: Zhang, Cheng-Mo
name: Zhang, Fan
name: Zhang, Hong-Mei
name: Zhang, Juan
name: Zhang, Tong
name: Zhang, Wan-Chang
name: Zhang, Wei
name: Zhang, Wen-Zhao
name: Zhang, Yi
name: Zhang, Yi-Fei
name: Zhang, Yong-Jie
name: Zhang, Yue
name: Zhang, Zhao
name: Zhang, Zhi
name: Zhang, Zi-Liang
name: Zhao, Hai-Sheng
name: Zhao, Xiao-Fan
name: Zheng, Shi-Jie
name: Zhou, Deng-Ke
name: Zhou, Jian-Feng
name: Zhu, Yu-Xuan
name: Zhu, Yue
name: Zhuang, Ren-Lin
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: Low-frequency quasi-periodic oscillations (LFQPOs) are commonly found in black hole X-ray binaries, and their origin is still under debate. The properties of LFQPOs at high energies (above 30 keV) are closely related to the nature of the accretion flow in the innermost regions, and thus play a crucial role in critically testing various theoretical models. The Hard X-ray Modulation Telescope (Insight-HXMT) is capable of detecting emissions above 30 keV, and is therefore an ideal instrument to do so. Here we report the discovery of LFQPOs above 200 keV in the new black hole MAXI J1820+070 in the X-ray hard state, which allows us to understand the behaviours of LFQPOs at hundreds of kiloelectronvolts. The phase lag of the LFQPO is constant around zero below 30 keV, and becomes a soft lag (that is, the high-energy photons arrive first) above 30 keV. The soft lag gradually increases with energy and reaches ~0.9s in the 150-200 keV band. The detection at energies above 200 keV, the large soft lag and the energy-related behaviors of the LFQPO pose a great challenge for most currently existing models, but suggest that the LFQPO probably originates from the precession of a small-scale jet.
description: 36 pages, 12 figures, 3 tables; published in Nature Astronomy