GCN Circular 39380
Subject
GRB 250219A: SVOM/VT optical counterpart
Date
2025-02-20T04:10:03Z (2 days ago)
From
Liping Xin at NAOC, SVOM <xlp@nao.cas.cn>
Via
Web form
L.P. Xin, Y.L. Qiu, H.L. Li, C. Wu, Z.H. Yao, Y. N. Ma, X.H. Han, H.B. Cai, J. Wang, Y. Xu, J.Y. Wei (NAOC), R.Z. Li(YNAO), F. Daigne, M. Gnaoui (IAP) report on behalf of the SVOM team:
The SVOM/VT conducted a ToO follow-up observations of the GRB 250219A (Daigne
et al., GCN 39376) in VT_B (400nm-650nm) and VT_R (650nm-1000nm) channel simultaneously.
With the X band downlinked data, an uncatalogued optical source was clearly detected within the errorbox of Swift/XRT (Kennea et al., GCN 39379) in VT_R and VT_B stacked images, compared to the DESI catalogues.
The position is RA= 173.37166 deg, DEC= 22.70598 deg, J2000, corresponds to
RA = 11:33:29.2
DEC = +22:42:21.5
Error=0.5 arcsec
The source is brightening at the first phase during our observations and the brightness was estimated to be 22.1+/-0.2 mag in AB magnitude in VT_R, and 23.3+/-0.3 mag in AB magnitude in VT_B, at the mid time of 6.71 hours post the burst, with an exposure time of 16*100 seconds.
More deep follow-ups are encouraged.
The Space Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA, China), National Center for Space Studies (CNES, France) and the Chinese Academy of Sciences (CAS, China), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. VT was jointly developed by Xi'an Institute of Optics and Precision Mechanics (XIOPM), CAS and National astronomical observatories (NAOC),CAS.