TITLE: GCN CIRCULAR NUMBER: 36059 SUBJECT: EP240410a: GROND detection of a candidate counterpart DATE: 24/04/10 09:18:25 GMT FROM: Arne Rau at MPE <arau@mpe.mpg.de> Arne Rau (MPE): We observed the position of EP240408a (Hu et al., #GCN 36053; #36057) with the Gamma-ray Burst Optical Near-ir Detector (GROND, Greiner et al. 2008) starting on April 10, 2024, 04:14:09 UTC. A faint source is detected in the Swift/XRT error circle located at RA = 10:35:22.44, Dec = -35:44:08.2 with an uncertainty of 0.2” in both coordinates. The source is detected in the J and H bands at the following AB magnitudes: J= 19.9 +/- 0.3 H= 20.5 +/- 0.5 The photometric uncertainties are dominated by a very bright point source ~20 arcsec from the optical/NIR counterpart. We note that the source is also visible in the z-band data of the Legacy Survey DR10 (https://www.legacysurvey.org/). We thank the 2.2m staff member, Angela Hempel, for the rapid execution of the observation. View this GCN Circular online at https://gcn.nasa.gov/circulars/36059. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...