GCN Circular 37281
Subject
GRB 240824B: NOT optical upper limit
Date
2024-08-25T18:42:26Z (4 months ago)
From
Daniele B. Malesani at IMAPP / Radboud University <d.malesani@astro.ru.nl>
Via
Web form
D. B. Malesani (DAWN/NBI and Radboud Univ.), A. Martin-Carrillo (UCD), J. Terwel (NOT and TCD), report on behalf of a larger collaboration:
We observed the field of GRB 240824B (Fermi GBM team, GCN 37260; Nakajima et al., GCN 37261; DeLaunay et al., GCN 37267) using the Nordic Optical Telescope (NOT) located in the Canary Islands. Observations consisted of three r-band exposures for a total of 900 s, with a mid time 2024 Aug 25.053 UT (12.1 hr after the trigger). The seeing was unfortunately poor, with a delivered PSF of ~2".
In the stack of our images, no source is detected at a location consistent with the candidate X-ray afterglow error circle (Kennea et al., GCN 37270), down to a 3-sigma limiting magnitude r = 22 (AB, calibrated against nearby sources from the Pan-STARRS catalog).