TITLE:   GCN CIRCULAR
NUMBER:  36452
SUBJECT: GRB 240511A: J-band observations with WINTER
DATE:    24/05/13 01:40:47 GMT
FROM:    Geoffrey Mo at MIT <gmo@mit.edu>

Geoffrey Mo (MIT), Viraj Karambelkar (Caltech), Danielle Frostig (MIT), Benjamin Schneider (MIT), Robert Stein (Caltech), Nathan Lourie (MIT), Tomas Ahumada (Caltech), Robert Simcoe (MIT), and Mansi Kasliwal (Caltech) report:

We observed the field of GRB 240511A (Fermi GBM team, GCN 36428; Laha et al., GCN 36430) in the near-infrared J-band with the Palomar 1-m telescope, equipped with the 1 square degree WINTER camera (Lourie et al. 2020). 

Observations began at 2024-05-12T10:13:53 UTC (~16 hours after the GRB) and consisted of 15 x 120 s exposures. The images were processed using the WINTER data reduction pipeline (https://github.com/winter-telescope/mirar). 

We do not detect the optical counterpart discovered by NOT (Malesani et al., GCN 36442; Lipunov et al., GCN 36435; Lipunov et al., GCN 36436; Niwano et al., GCN 36445) at the Swift-XRT position of the afterglow (Evans et al., GCN 36431; Salvaggio et al., GCN 36443; Evans et al., GCN 36446) setting the following upper limit: J ~ 19.1 mag (AB).

WINTER (Wide-field INfrared Transient ExploreR) is a partnership between MIT and Caltech, housed at Palomar Observatory, and funded by NSF MRI, NSF AAG, the David and Lucille Packard Foundation, and the MIT Kavli Institute for Astrophysics and Space Research.