GRB 241213A: REM optical/NIR upper limits

We observed the field of GRB 241213A detected by Swift/BAT (Gupta et al., GCN 38547) 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, K bands, starting on 2024 December 13 at 03:50:29 UT (i.e. 1.5 hours after the Swift trigger), and lasting for about 1 hour. From preliminary photometry we do not detect any counterpart in the optical and NIR images at the enhanced Swift-XRT position (Osborne et al., GCN 38552) down to the following 3sigma magnitude upper limits: r > 19.5 (AB; calibrated against the PanSTARRS catalogue) at a mid-time of t - t0 = 2.1 hr after the trigger, J > 17.8 (Vega; calibrated against the 2MASS catalogue) at a mid-time of t - t0 = 2.2 hr after the trigger.