TITLE:   GCN CIRCULAR
NUMBER:  37499
SUBJECT: EP240913a: ESO-NTT optical observations
DATE:    24/09/14 11:26:08 GMT
FROM:    Paolo D'Avanzo at INAF - OAB <paolo.davanzo@inaf.it>

L. Asquini, M. Landoni, P. D'Avanzo, S. Campana (INAF-Brera), C. Farias (ESO/ La Silla) report:


We observed the field of EP 240913A (Li et al., GCN Circ. 37492), which has been proposed to be a GRB event (Yin et al., GCN Circ. 37493), with the ESO-NTT telescope equipped with EFOSC2 starting at 2024-09-14T05:58:49 UT (i.e. about 18.3 hours after the EP T0), during an on-site test run for the scheduler of the incoming SOXS instrument. 
Observations have been carried out in imaging mode with the Gunn r and i filters. 

No optical counterpart is detected within the Swift-XRT error circle of the proposed X-ray counterpart (Jian et al., GCN Circ. 37497).

From preliminary photometry, we estimate a 3sigma limit of r ~ 23.5 mag (AB; calibrated against the PanSTARRS catalogue),. 

Further analysis is ongoing.