TITLE:   GCN CIRCULAR
NUMBER:  35773
SUBJECT: EPW20240219aa is Likely a GRB Event
DATE:    24/02/22 16:29:47 GMT
FROM:    Binbin Zhang at Nanjing U <bbzhang@nju.edu.cn>

Binbin Zhang (NJU), Hui Sun (NAOC), Yi-Han Iris Yin (NJU), Jun Yang (NJU), Bing Zhang (UNLV), Xuefeng Wu (PMO) report on behalf of large collaboration:

Our team has followed up on EP's initial X-ray flare detection (EPW20240219aa; ATel 16463; ATel 16472) and discovered a weak, untriggered gamma-ray transient in the Fermi/GBM data at 2024-02-19T06:21:42 UTC. This transient lasted approximately 50 seconds and its location aligns with that of EPW20240219aa. 

Considering the factors that the gamma-ray transient is consistent with EPW20240219aa in terms of event time, duration, and location, we are inclined to believe that this is a GRB event. A preliminary spectral analysis indicates that its peak energy reaches a few hundred keV, which further supports its classification as a GRB. 

We strongly recommend further follow-up on EPW20240219aa to confirm its physical nature and to detect any afterglows.