GCN Circular 42229
Subject
GRB 251013C: LCO optical afterglow detection
Event
Date
2025-10-13T21:13:53Z (2 days ago)
From
SVOM_group <svomgroup@bao.ac.cn>
Via
Web form
J. T. Palmerio, D. Turpin, A. Saccardi, B. Cordier (CEA/Irfu), L. P. Xin (NAOC), C. Wu (NAOC), report on behalf of the SVOM mission team:
We observed the field of GRB 251013C (SVOM/ECLAIRs and GRM, Rakotondrainibe et al. GCN 42223; Fermi/GBM, Fermi GBM team, GCN 42221) with the LCO 1m telescope at South African Astronomical Observatory equipped with the Sinistro instrument. Our observation started at 2025-10-13T19:27:33.084 about 1.8 hours after the SVOM/ECLAIRs T0 time.
We obtained 3 series of 3x200 s exposures in the SDSS gri filters. The bright optical counterpart detected by SVOM/VT (Palmerio et al. GCN 42223), BOOTES-6 (Perez-Garcia et al., GCN 42225), LAST (Konno et al., GCN 42226), NOT (Martin-Carrillo et al., GCN 42227 and the Visual Telescope Project (Masi et al., GCN 42228) is clearly detected in our first images subtracted to the Pan-STARRS DR2 catalog image. We measure the following magnitude:
g = 16.30 +/- 0.01 (AB), at Tmid-T0 = 2.1 hours
r = 15.99 +/- 0.01 (AB), at Tmid-T0 = 2.0 hours
i = 15.70 +/- 0.01 (AB), at Tmid-T0 =1.8 hours
Further observations are planned and spectroscopic observations are encouraged.
This project is funded by the SVOM collaboration.