Insights into the X-Ray Burst Pulse Morphology from SGR J1935+2154

• Published in: The Astrophysical journal. Supplement series Vol. 279; no. 1; pp. 14 - 26
• Main Authors: Yang, Jiao-Jiao, Xiao, Shuo, Wang, Yue, Xiong, Shao-Lin, Lin, Lin, Jiang, Zheng-Huo, Liao, Tong-Lei, Li, Xiao-Bo, Li, Cheng-Kui, Yi, Shu-Xu, Zhang, Zhen, Zhang, Shuang-Nan
• Format: Journal Article
• Language: English
• Published: Saskatoon The American Astronomical Society 01.07.2025; IOP Publishing
• Subjects: Correlation; Decay; Gamma ray bursts; Gamma rays; Gravitational waves; Magnetars; Milky Way; Normal distribution; Parameters; Pulse duration; Radio bursts; X ray telescopes; X-ray bursts; X-rays
• ISSN: 0067-0049; 1538-4365
• DOI: 10.3847/1538-4365/addb42

SGR J1935+2154 is an extremely active magnetar and the source of the first fast radio burst in the Milky Way, characterized as a magnetar X-ray burst, but whether the temporal features of this magnetar are specific or not is not well known. Based on data from the Fermi Gamma-ray Burst Monitor (GBM), Gravitational Wave High-energy Electromagnetic Counterpart All-Sky Monitor (GECAM), and Hard X-ray Modulation Telescope (HXMT), we investigate the temporal properties of pulses and bursts, covering parameters such as the minimum variability timescale (MVT), duration, rise/decay/waiting times, skewness, peakedness, pulse width, and number of pulses. Except for the number of pulses, all parameters follow the log-Gaussian distribution. In the GBM and GECAM data, MVT and duration exhibit a negative correlation, while the number of pulses and duration (or MVT) exhibit a positive (or negative) correlation. Universal power-law relationships exist among parameters, for example, rise time is positively correlated with decay time, while decay/rise time (or width) and peakedness show a negative correlation. We did not find a significant difference compared with another magnetar, SGR J0501+4516. Finally, the parameters observed by GBM and GECAM show no significant differences, but some parameters observed by HXMT differ from both, suggesting that they may originate from a different physical mechanism.