GCN Circular 46041
Tanishk Mohan (IITB), Geoffrey Mo (Caltech/Carnegie), Benjamin Schneider (LAM), Viraj Karambelkar (Columbia), Tomas Ahumada (NOIRLab), Robert Stein (UMD), Danielle Frostig (CfA), Nathan Lourie (MIT), Robert Simcoe (MIT), and Mansi Kasliwal (Caltech) report:
We observed the field of GRB 261026A (Goto et al., GCN 46030) in the near-infrared J band with the Palomar 1-m telescope, equipped with the 1.2-square degree WINTER camera (Lourie et al. 2020, Frostig et al. 2024).
Observations began on 2026-10-26 at 06:22:15.440 UTC in the J band (12.6 min after the SVOM/ECLAIRs trigger), consisting of 15*120 sec exposures. The images were processed using the WINTER data reduction pipeline implemented with mirar (https://github.com/winter-telescope/mirar, https://doi.org/10.5281/zenodo.13352565).
We detect a source present at the optical counterpart position in our stacked image and obtain the following magnitude: J = 18.55 +- 0.1 mag (AB) in our stacked image. Optical counterpart is also detected by Dornic et al., GCN 46033; Zheng et al., GCN 46034; Wu et al., GCN 46035.
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 Lucile Packard Foundation, and the MIT Kavli Institute for Astrophysics and Space Research.