TITLE:   GCN CIRCULAR
NUMBER:  36256
SUBJECT: LIGO/Virgo/KAGRA S240422ed: No Counterparts in DDOTI/OAN Optical Observations
DATE:    24/04/23 14:44:02 GMT
FROM:    Rosa L. Becerra at Tor Vergata, Roma <rosa.becerra@roma2.infn.it>

Rosa L. Becerra (UTOV), Alan M. Watson (UNAM), Simone Dichiara (PSU), Eleonora Troja (UTOV), Nat Butler (ASU), William H. Lee (UNAM), Alexander Kutyrev (GSFC/UMD), Tsvetelina Dimitrova (ASU), Keneth Garcia Cifuentes (UNAM), Camila Angulo Valdez (UNAM), Margarita Pereyra (UNAM) and Océlotl Lopez (UNAM) report:

We observed LIGO/Virgo/KAGRA S240422ed (GCN #36236) with the DDOTI/OAN wide-field imager at the Observatorio Astronomico Nacional on Sierra San Pedro Martir (http://ddoti.astroscu.unam.mx) on the night of 2024-04-23 UTC.

We tiled the LVK localization with two pointings covering about 104 square degrees and including about 42% of the probability in the current BAYESTAR map. 

We observed from 2024-04-23 03:15 UTC to 2024-04-23 05:04 UTC (from T+5.7 to
T+7.5 hours after the event) obtaining a total of 54 minutes of exposure across the fields in the w filter, with 10-sigma limiting magnitudes of w~19 and constrained by the horizon.

Comparing our observations to the USNO-B1 and PanSTARRS PS1 DR2 catalogs we
detect no uncatalogued sources within the observed field to our 10-sigma
limit. 

Further observations are planned.

We thank the staff of the Observatorio Astronomico Nacional in San Pedro
Martir.