Return of 4U 1730–22 after 49 yr Silence: The Outburst Properties Observed by NICER and Insight-HXMT

• Published in: Astrophysical journal. Letters Vol. 942; no. 1; p. L12
• Main Authors: Chen, Yu-Peng, Zhang, Shu, Zhang, Shuang-Nan, Ji, Long, Wang, Peng-Ju, Kong, Ling-Da, Chang, Zhi, Peng, Jing-Qiang, Shui, Qing-Cang, Li, Jian, Tao, Lian, Ge, Ming-Yu, Qu, Jin-Lu
• Format: Journal Article
• Language: English
• Published: Austin The American Astronomical Society 01.01.2023; IOP Publishing
• Subjects: Accretion disks; Corotation; Emission; Low-mass x-ray binary stars; Luminosity; Magnetic fields; Magnetospheres; Neutron stars; Outbursts; X-ray transient sources

After 49 yr of quiescence, 4U 1730–22 became active and had two outbursts in 2021 and 2022; the onset and tail of the outbursts were observed by NICER, which give us a peerless opportunity to study the state transition and its underlying mechanism. In this work, we take both the neutron star (NS) su...