TITLE:   GCN CIRCULAR
NUMBER:  39845
SUBJECT: GRB 250322A: VLT optical observations
DATE:    25/03/23 02:42:36 GMT
FROM:    Rosa L. Becerra at Tor Vergata, Roma <rosa.becerra@roma2.infn.it>


Rosa Becerra (U Rome), Yu-Han Yang (U Rome), Eleonora Troja (U Rome) report on behalf of the ERC BHianca team:

We observed the field of GRB 250322A (Gupta et al., GCN 39835, Goad et al. GCN 39841) with the FORS2 imager on the ESO VLT UT1 (Antu). Observations began at T+8.1 hours after the trigger and were carried out in the R filter with a total exposure of 1200 seconds, at an average seeing of 0.5" and airmass about 1.2. 

We do not detect any new source at the enhanced Swift-XRT position (Goad et al. GCN 39841) down to the following 5-sigma limit R>25.8 AB mag calibrated with nearby Pan-STARRS stars and without Galactic extinction correction. 

In our images, we detect the host galaxy candidate reported by Martin-Carrillo et al. (GCN 39842) with no significant variation in brightness.

We thank the staff at the VLT for the rapid execution of these observations.