Periodicity Search on X-ray Bursts of SGR J1935+2154 Using 8.5-year Fermi/GBM Data

Jin-Hang Zou, Bin-Bin Zhang, Guo-Qiang Zhang, Yu-Han Yang, Fa-Yin Wang, Lang Shao

Published 2021-07-08Version 1

We performed a systematic search for X-ray bursts of the SGR J1935+2154 using the Fermi Gamma-ray Burst Monitor continuous data dated from Jan 2013 to July 2021. Seven major bursting phases, which consist of a total of 253 individual bursts, are identified. We further analyze the periodic properties of our sample using the Lomb-Scargle spectrum and a novel model (named "Simple Period Model") developed by ourselves. Two methods yield the same results in that those bursts exhibit a period of ~237 days with a ~58.6% duty cycle. Based on our analysis, we further predict two upcoming active windows of the X-ray bursts. As of July 7th, 2021, the beginning date of our first perdition has been confirmed by the ongoing X-ray activities of the SGR J1935+2154.