TITLE:   GCN CIRCULAR
NUMBER:  40305
SUBJECT: GRB 250430A: DDOTI Optical Observations
DATE:    25/05/01 14:06:36 GMT
FROM:    sahil.atri@students.uniroma2.eu

Sahil Atri (U Roma), Rosa L. Becerra (U Roma), Alan M. Watson (UNAM), Camila Angulo Valdez (UNAM), Sahil Atri (U Roma), Nat Butler (ASU), Simone Dichiara (Penn State University), Tsvetelina Dimitrova (ASU), Alexander Kutyrev (GSFC/UMD), William H. Lee (UNAM), and Océlotl López (UNAM), Margarita Pereyra (UNAM) and Eleonora Troja (U Roma) report:

We observed the field of the Swift/BAT GRB 250430A (Parsotan et al., GCN Circ. 40292) with the DDOTI/OAN wide-field imager at the Observatorio Astronómico Nacional on the Sierra of San Pedro Martir (http://ddoti.astroscu.unam.mx) on the night of 2025-05-01 UTC.

DDOTI observed the Swift/UVOT error region (Parsotan et al., GCN Circ. 40292) from 05:23 UTC to 10:43 UTC (from T+11.9 h to T+17.4 h after the trigger) with a total exposure of 2.3 hours, alternating with other scientific programs. 

Comparing our observations to the USNO-B1 and PanSTARRS PS1 DR2 catalogues, we detect no any uncatalogued source at the position reported by Parsotan et al., (GCN Circ. 40292); Odeh et al., (GCN Circ. 40295); Wang et al., (GCN Circ. 40299); Garnichey et al., (GCN Circ. 40301); Hagio  et al., (GCN Circ. 40302); Quadri (GCN Circ. 40303) and Moretti (GCN Circ. 40304) down to a 3-sigma limiting AB magnitude of:

w > 20.6

We thank the staff of the Observatorio Astronómico Nacional on the Sierra of San Pedro Mártir.