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arXiv · 2009.10607

Discovery of oscillations above 200 keV in a black hole X-ray binary with Insight-HXMT

Xiang Ma·Lian Tao·Shuang-Nan Zhang·Liang Zhang·Qing-Cui Bu·Ming-Yu Ge·Yu-Peng Chen·Jin-Lu Qu·Shu Zhang·Fang-Jun Lu·Li-Ming Song·Yi-Jung Yang·Feng Yuan·Ce Cai·Xue-Lei Cao·Zhi Chang·Gang Chen·Li Chen·Tian-Xiang Chen·Yi-Bao Chen·Yong Chen·Wei Cui·Wei-Wei Cui·Jing-Kang Deng·Yong-Wei Dong·Yuan-Yuan Du·Min-Xue Fu·Guan-Hua Gao·He Gao·Min Gao·Yu-Dong Gu·Ju Guan·Cheng-Cheng Guo·Da-Wei Han·Yue Huang·Jia Huo·Long Ji·Shu-Mei Jia·Lu-Hua Jiang·Wei-Chun Jiang·Jing Jin·Yong-Jie Jin·Ling-Da Kong·Bing Li·Cheng-Kui Li·Gang Li·Mao-Shun Li·Ti-Pei Li·Wei Li·Xian Li·Xiao-Bo Li·Xu-Fang Li·Yan-Guo Li·Zheng-Wei Li·Xiao-Hua Liang·Jin-Yuan Liao·Bai-Sheng Liu·Cong-Zhan Liu·Guo-Qing Liu·Hong-Wei Liu·Xiao-Jing Liu·Yi-Nong Liu·Bo Lu·Xue-Feng Lu·Qi Luo·Tao Luo·Bin Meng·Yi Nang·Jian-Yin Nie·Ge Ou·Na Sai·Ren-Cheng Shang·Xin-Ying Song·Liang Sun·Ying Tan·Yuo-Li Tuo·Chen Wang·Guo-Feng Wang·Juan Wang·Ling-Jun Wang·Wen-Shuai Wang·Yu-Sa Wang·Xiang-Yang Wen·Bai-Yang Wu·Bo-Bing Wu·Mei Wu·Guang-Cheng Xiao·Shuo Xiao·Fu-Guo Xie·Shao-Lin Xiong·He Xu·Yu-Peng Xu·Jia-Wei Yang·Sheng Yang·Yan-Ji Yang·Qi-Bin Yi·Qian-Qing Yin·Yuan You·Ai-Mei Zhang·Cheng-Mo Zhang
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Abstract

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.

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Xiang Ma, Lian Tao, Shuang-Nan Zhang, Liang Zhang, Qing-Cui Bu, Ming-Yu Ge, Yu-Peng Chen, Jin-Lu Qu, Shu Zhang, Fang-Jun Lu, Li-Ming Song, Yi-Jung Yang, Feng Yuan, Ce Cai, Xue-Lei Cao, Zhi Chang, Gang Chen, Li Chen, Tian-Xiang Chen, Yi-Bao Chen, Yong Chen, Wei Cui, Wei-Wei Cui, Jing-Kang Deng, Yong-Wei Dong, Yuan-Yuan Du, Min-Xue Fu, Guan-Hua Gao, He Gao, Min Gao, Yu-Dong Gu, Ju Guan, Cheng-Cheng Guo, Da-Wei Han, Yue Huang, Jia Huo, Long Ji, Shu-Mei Jia, Lu-Hua Jiang, Wei-Chun Jiang, Jing Jin, Yong-Jie Jin, Ling-Da Kong, Bing Li, Cheng-Kui Li, Gang Li, Mao-Shun Li, Ti-Pei Li, Wei Li, Xian Li, Xiao-Bo Li, Xu-Fang Li, Yan-Guo Li, Zheng-Wei Li, Xiao-Hua Liang, Jin-Yuan Liao, Bai-Sheng Liu, Cong-Zhan Liu, Guo-Qing Liu, Hong-Wei Liu, Xiao-Jing Liu, Yi-Nong Liu, Bo Lu, Xue-Feng Lu, Qi Luo, Tao Luo, Bin Meng, Yi Nang, Jian-Yin Nie, Ge Ou, Na Sai, Ren-Cheng Shang, Xin-Ying Song, Liang Sun, Ying Tan, Yuo-Li Tuo, Chen Wang, Guo-Feng Wang, Juan Wang, Ling-Jun Wang, Wen-Shuai Wang, Yu-Sa Wang, Xiang-Yang Wen, Bai-Yang Wu, Bo-Bing Wu, Mei Wu, Guang-Cheng Xiao, Shuo Xiao, Fu-Guo Xie, Shao-Lin Xiong, He Xu, Yu-Peng Xu, Jia-Wei Yang, Sheng Yang, Yan-Ji Yang, Qi-Bin Yi, Qian-Qing Yin, Yuan You, Ai-Mei Zhang, Cheng-Mo Zhang. 2020-09-22. Discovery of oscillations above 200 keV in a black hole X-ray binary with Insight-HXMT. https://doi.org/10.1038/s41550-020-1192-2

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