Multi-Instrument Search for Gamma-Ray Counterpart of X-ray Transients detected by EP/WXT

Yan-Qiu Zhang; Wang-Chen Xue; Jin-Peng Zhang; Ce Cai; Shao-Lin Xiong; Cheng-Kui Li; Yuan Liu; Chen-Wei Wang; Hao-Xuan Guo; Shuo Xiao; Wen-Jun Tan; Chao Zheng; Jia-Cong Liu; Sheng-Lun Xie; Peng Zhang; Wen-Long Zhang; Yue Wang; Zheng-Hang Yu; Yang-Zhao Ren; Ping Wang; Yue Huang; Xiao-Bo Li; Xiao-Yun Zhao; Shi-Jie Zheng; Zhen Zhang; Shu-Xu Yi; Li-Ming Song; Shuang-Nan Zhang

arXiv · 2506.05920

Multi-Instrument Search for Gamma-Ray Counterpart of X-ray Transients detected by EP/WXT

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Abstract

As a soft X-ray imager with unprecedentedly large field of view, EP/WXT has detected many (fast) X-ray transients, whose nature is very intriguing. Whether there is gamma-ray counterpart for the X-ray transient provides important implications for its origin. Some of them have been reported to be associated with GRB, however, a systematic study on the gamma-ray emission of these X-ray transients is lacking. In this work, we implemented a comprehensive targeted search for gamma-ray counterparts to 63 X-ray transients reported by EP/WXT during its first year of operation, using the dedicated multiple-instrument search pipeline, ETJASMIN, with GECAM-B, GECAM-C, Fermi/GBM, and \textit{Insight}-HXMT data. We find that 14 out of 63 (22\%) EP/WXT X-ray transients have gamma-ray counterparts. For other transients, ETJASMIN pipeline provided upper limit of gamma-ray emission, which is more stringent than that given by individual instrument. Moreover, we investigated the properties of the X-ray transients and their gamma-ray counterparts, and explored the relation between the x-ray transient and gamma-ray counterpart.

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Yan-Qiu Zhang, Wang-Chen Xue, Jin-Peng Zhang, Ce Cai, Shao-Lin Xiong, Cheng-Kui Li, Yuan Liu, Chen-Wei Wang, Hao-Xuan Guo, Shuo Xiao, Wen-Jun Tan, Chao Zheng, Jia-Cong Liu, Sheng-Lun Xie, Peng Zhang, Wen-Long Zhang, Yue Wang, Zheng-Hang Yu, Yang-Zhao Ren, Ping Wang, Yue Huang, Xiao-Bo Li, Xiao-Yun Zhao, Shi-Jie Zheng, Zhen Zhang, Shu-Xu Yi, Li-Ming Song, Shuang-Nan Zhang. 2025-06-06. Multi-Instrument Search for Gamma-Ray Counterpart of X-ray Transients detected by EP/WXT. https://arxiv.org/abs/2506.05920

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