近日，武汉大学的王伟及其研究小组与美国内华达大学的Bing Zhang等人合作并取得一项新进展。经过不懈努力，他们揭示了微类星体的亚秒周期性射电振荡现象。相关研究成果已于2023年7月26日在国际权威学术期刊《自然》上发表。

该研究团队报道了2021年1月和2022年6月在1.05至1.45 GHz的射电频段中观察到了源的约5 Hz瞬态周期性振荡特征。在振荡相位中还观察到圆偏振。

据悉，强大的相对论喷流是所有尺度的吸积黑洞普遍存在的特征之一。GRS 1915+105是一个著名的高速旋转黑洞X射线双星，具有相对论喷流，被称为“微类星体”，其射电发射的超光速运动表明了这一点。在过去的30年里，它表现出持续的X射线活动，准周期振荡约为1-10Hz，X射线频段为34和67Hz。这些振荡可能起源于内部吸积盘，但也有其他起源的可能性。射电观测发现具有准周期耀斑或振荡的可变光曲线，周期约为20 - 50分钟。

附：英文原文

Title: Subsecond periodic radio oscillations in a microquasar

Author: Tian, Pengfu, Zhang, Ping, Wang, Wei, Wang, Pei, Sun, Xiaohui, Liu, Jifeng, Zhang, Bing, Dai, Zigao, Yuan, Feng, Zhang, Shuangnan, Liu, Qingzhong, Jiang, Peng, Wu, Xuefeng, Zheng, Zheng, Chen, Jiashi, Li, Di, Zhu, Zonghong, Pan, Zhichen, Gan, Hengqian, Chen, Xiao, Sai, Na

Issue&Volume: 2023-07-26

Abstract: Powerful relativistic jets are one of the ubiquitous features of accreting black holes in all scales. GRS 1915+105 is a well-known fast-spinning black-hole X-ray binary with a relativistic jet, termed a ‘microquasar’, as indicated by its superluminal motion of radio emission. It has exhibited persistent X-ray activity over the last 30years, with quasiperiodic oscillations of approximately 1–10Hz and 34 and 67Hz in the X-ray band. These oscillations probably originate in the inner accretion disk, but other origins have been considered. Radio observations found variable light curves with quasiperiodic flares or oscillations with periods of approximately 20–50min. Here we report two instances of approximately 5-Hz transient periodic oscillation features from the source detected in the 1.05- to 1.45-GHz radio band that occurred in January 2021 and June 2022. Circular polarization was also observed during the oscillation phase.

DOI: 10.1038/s41586-023-06336-6

Source: https://www.nature.com/articles/s41586-023-06336-6