GCN Circular 42990
Subject
EP251130a: JinShan near-infrared observations
Event
Date
2025-12-04T16:38:15Z (4 days ago)
From
syfu@nao.cas.cn
Via
Web form
S.Y. Fu (HUST), L.B. He (NAOC), A.D. Zhu, L. Lei, H.Z. Wu, W.H. Lei (HUST), J. An, S.Q. Jiang, X. Liu, Z.P. Zhu, D. Xu (NAOC), J.Z. Liu (XAO)
We continued monitoring the optical counterpart of EP251130a (Wu et al., GCN 42903) using the 100C telescope, equipped with the INS-BIue SWIR camera, of the JinShan project, located at Altay, Xinjiang, China. Observation started at 2025-12-01 16:29:07 UT, i.e., 1.22 days post-burst, and a series of J-band frames were obtained.
The previously reported optical counterpart (Dornic et al., GCN 42904; He et al. GCN 42914; Gupta et al. GCN 42916; Zheng et al. GCN 42917; Dalen et al. GCN 42918; Moskvitin
& Spiridonova, GCN 42919; Aryan et al. GCN 42921; Volnova et al. GCN 42922; Ma et al. GCN 42940; Corcoran et al. GCN 42951; Rodríguez et al. GCN 42963; Abidkhanov et al. GCN 42969) was detected in our stacked J-band frame with magnitude J = 19.19 +/- 0.12 (Vega) at a mid-time 1.32 days post-burst. The magnitude was calibrated with the nearby 2MASS catalog and without the Galactic extinction correction.
We acknowledge the excellent support from T.Q. Chen and J.F. Zhang for enabling these observations.