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GCN Circular 33671

GRB230420A: VLT optical observation
2023-04-21T17:10:28Z (a year ago)
Hallie Fausey at George Washington U <>
H. Fausey (GWU), B. Schneider (MIT),  C. C. Thoene (ASU-CAS), D. B. Malesani (Radboud Univ. and DAWN/NBI), and S. Campana (INAF-OAB) report on behalf of the Stargate collaboration:

We observed the field of GRB230420A (Klinger et al., GCN33658) with the ESO VLT UT3 (Melipal) using the acquisition camera of the X-shooter spectrograph. We took a 300s r-band image on 2023 April 20.105 UT (16 hours after the BAT trigger).

At the coordinates of the optical afterglow (Hu et al., GCN 33663; Fu et al., GCN 33665), we detect a faint source with magnitude r' = 23.2 +/- 0.1 (AB). The magnitude is consistent, within the errors, to the value reported by Fu et al. (GCN 33665). We note the presence of a marginally-detected object in the Legacy Survey at the same coordinates, which, if real, could be the GRB host galaxy.

We acknowledge the excellent support from the ESO observing staff in Paranal, in particular Zahed Wahhaj.
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