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GCN Circular 35333

GRB 231210B: REM optical/NIR upper limits
2023-12-14T12:04:18Z (5 months ago)
Matteo Ferro <>
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M. Ferro, R. Brivio, P. D'Avanzo, S. Covino, D. Fugazza (INAF-OAB) on behalf of the REM team, report:

We observed the field of GRB 231210B (Page et al., GCN 35314) with the REM 60cm robotic telescope located at the ESO Observatory of La Silla (Chile). The observations were carried out in the g,r,i,z, J,H,K bands, starting on 2023 Dec 11 at 00:36:37 UT (i.e. about 3.13 hours after the Swift trigger) and lasted for about 1 hour.
From preliminary analysis, we do not find any source at the enhanced XRT position (Beardmore et al., GCN 35318), down the the following 3 sigma upper limits:

r > 21.0 (AB; calibrated against the SkyMapper catalogue)
at a mid time of t-t0 ~ 3.80 h after the GRB trigger;

H > 17.4 (Vega; calibrated against the 2MASS catalogue)
at a mid time of t-t0 ~ 3.56 h after the GRB trigger.
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