TITLE:   GCN CIRCULAR
NUMBER:  40161
SUBJECT: IceCube-250416A: DDOTI Optical Observations
DATE:    25/04/17 14:21:17 GMT
FROM:    Rosa L. Becerra at Tor Vergata, Roma <rosa.becerra@roma2.infn.it>

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

We observe the field of the IceCube-250416A (bronze) (IceCube Collaboration, GCN Circ. 40153) event 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 2025-04-17 UTC.

DDOTI observed from 03:20 UTC to 04:31 UTC (from T+8.8 h to T+10.0 h after the trigger) with a total exposure of 24 min, alternating with other scientific programs.

Comparing our observations to the USNO-B1 and PanSTARRS PS1 DR2 catalogues and after performed image subtraction against PanSTARRS PS1 DR2, we detect no uncatalogued sources within the observed field to an average 5-sigma limiting AB magnitude of:

w > 20.5.

This value has not been corrected for Galactic extinction (A_r​∼1.7 mag; Schlafly et al. 2011).

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