GCN Circular 45442
Subject
GRB 260822A: SVOM/VT optical upper limits
Event
Date
2026-08-25T18:13:04Z (6 days ago)
From
Huali Li at at NAOC, SVOM <lhl@nao.cas.cn>
Via
Web form
H. L. Li, L. P. Xin, C. Wu, Y. N. Ma, Y. L. Qiu, Z. H. Yao, J. R. Xu, X. H. Han, J. Wang, Y. Xu, P. P. Zhang, W. J. Xie, Y. J. Xiao, H. B. Cai, J. S. Deng, J. Y. Wei (NAOC) and J. T. Palmerio (CEA/Irfu) report on behalf of the SVOM/VT team.
SVOM/VT performed two additional ToO observations of GRB 260822A (sb26082201, Schanne et al., GCN 45422) at mid-times of 18.9 h and 23.8 h in the VT_B (400-650 nm) and VT_R (650-1000 nm) channels simultaneously.
No credible candidate was found in the stacked images of each epoch from both the earlier VT observations (Li et al., GCN 45430) and the present ToO observations, within the SVOM/ECLAIRs error box (Schanne et al., GCN 45422) and the Einstein Probe positions (Turpin et al., GCN 45436).
The typical 5-sigma upper limits are 23.0 mag in both channels. Our measurements are in AB magnitudes and are not corrected for Galactic extinction.
This non-detection is consistent with the reports from GOTO (O'Neill et al., GCN 45423), GROWTH-India (Saikia et al., GCN 45424), LCO (Turpin et al., GCN 45427) and PRIME (Durbak et al., GCN 45437).
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.