TITLE:   GCN CIRCULAR
NUMBER:  37685
SUBJECT: GRB241001A: REM optical/NIR upper limits
DATE:    24/10/02 18:14:47 GMT
FROM:    Matteo Ferro at INAF-OAB <matteo.ferro@inaf.it>

M. Ferro, R. Brivio, P. D’Avanzo, Y.-D. Hu, S. Covino, and D. Fugazza (INAF-OAB) report on behalf of the REM team:
We observed the field of GRB 241001A, detected by SVOM/ECLAIRs (Dagoneau et al. GCN 37655), with the REM 60cm robotic telescope located at the ESO observatory of La Silla (Chile). The observations were carried in the g, r, i, z, J, H bands, starting on 2024 October 02 at 05:31:19 UT (i.e. 12.38 hours after the SVOM trigger), and lasting for about 1.5 hours.
From preliminary photometry we do not detect any optical/NIR counterpart at the afterglow position (Osborne et al. GCN 37670; Izzo & Malesani, GCN 37673; Breeveld et al. GCN 37678; Turpin et al. GCN 37679) down to the following 3sigma magnitude upper limits:
H > 18.3
(Vega; calibrated against the 2MASS catalogue)

r > 19.3
(AB; calibrated against the SkyMapper catalogue)

at a mid-time of t - t0 = 13.13 hours after the trigger.