GCN Circular 39578
Subject
EP250302a: SVOM/VT optical observation
Date
2025-03-04T02:15:58Z (3 months ago)
From
SVOM_group <svomgroup@bao.ac.cn>
Via
Web form
C. Wu, D. H. Zhao, Y. N. Ma, L. P. Xin, Y. L. Qiu, H. L. Li, Z. H. Yao, Y. Xu, P. P. Zhang, W. J. Xie, J. Wang, X. H. Han, Y. J. Xiao, H. B. Cai, J. Y. Wei(NAOC), J. T. Palmerio(CEA/Irfu) report on behalf of the SVOM team:
The SVOM/VT conducted a ToO follow-up observations of the EP250302a (Zhu et al., GCN 39550) in VT_B (400nm-650nm) and VT_R (650nm-1000nm) channel simultaneously.
The optical counterpart of EP250302a(Trigger ID: 01709132186, Zhu et al., GCN 39550; Busmann et al., GCN 39551; Leonini et al., GCN 39553; Wu et al., GCN 39555; Xin et al., GCN 39558; Adami et al., GCN 39560; Yang et al., GCN 39561; Becerra et al., GCN 39562; Izzo et al., GCN 39564; Pankov et al., GCN 39565; Reguitti, GCN 39568; Komesh et al., GCN 39569; Shilling and Breeveld, GCN 39570; Aryan et al., GCN 39572, Moskvitin et al., GCN 39576) was clearly detected in VT_R and VT_B images.
The brightness in AB manigutude was estimated to be 21.41 +/-0.09 mag in VT_R (stacked image: 50x60s), and 22.68 +/-0.14 mag in VT_B (stacked iamge: 50x60s), measured at the mid time of 1.03 days post the burst.
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.