TITLE: GCN CIRCULAR NUMBER: 40000 SUBJECT: GRB 250219A: NOT candidate host galaxy detection DATE: 25/04/01 09:28:18 GMT FROM: Daniele B. Malesani at IMAPP / Radboud University d.malesani@astro.ru.nl

Daniele B. Malesani (DAWN/NBI and Radboud Univ.), Benjamin Schneider (LAM), Gregory Corcoran (UCD), A. Martin-Carrillo (UCD), and Nikko Pyykkinen (NOT and Turku) report on behalf of a larger collaboration:

We observed the field of GRB 250219A (Daigne et al., GCN 39376) using the Nordic Optical Telescope (NOT) equipped with the ALFOSC imager. Observations were carried out with the r-band filter and started on 2025 March 26 at 02:18 UT (34.4 days after the GRB), for a total of 50 min on source. Seeing and Moon conditions were favorable.

Consistent with the position of the optical afterglow (Xin et al., GCN 39380; Magnani et al., GCN 39382; Fu et al., GCN 39383), we detect a faint object with AB magnitude r = 25.2 +- 0.3, calibrated against nearby objects from Pan-STARRS.

While we note a slight offset (~0.9") compared to the afterglow position (Fu et al., GCN 39383), we suggest the above object to be a candidate host galaxy of GRB 250219A.

We thank Liping Xin, Francis Fortin and Susanna Vergani for helpful discussion.

View this GCN Circular online at https://gcn.nasa.gov/circulars/40000. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...