GCN Circular 46256
A.P. Saikia, A. Sarkar, Harshita, S. Patil, V. Swain, V. Bhalerao (IITB), G.C. Anupama, S. Barway (IIA) and R. Norboo (IAO) report on behalf of the GIT team:
We observed the field of GRB 261113A by SVOM/ECLAIRs & SVOM/GRM (Saccardi et al., GCN 46244) with 0.7m GROWTH-India Telescope (GIT). We started the observation at 2026-11-13 15:12:50 UT, i.e., 41.82 minutes after the SVOM GRM trigger. We obtained multiple exposures of 300 and 360 seconds in r' filter. We clearly detected the afterglow in our individual images at the positions given by Lin et. al., (GCN 46247). The photometry result follows as:
| MJD (mid) | t-t0 (hr) | Filter | Exposure Time (s) | Magnitude (AB) | Limiting Magnitude (5-sigma) |
|---|---|---|---|---|---|
| 61357.63565 | 0.74 | r' | 300 | 19.31 +/- 0.04 | 20.88 |
| 61357.68037 | 1.81 | r' | 360 | 20.00 +/- 0.09 | 20.57 |
Our result is consistent with Lin et al., (GCN 46247), Lei et al., (GCN 46248), Li et al., (GCN 46249), Yin et al., (GCN 46250), Chen et al., (GCN 46251), Xin et al., (GCN 46252), Zhao et al., (GCN 46253), Li et al., (GCN 46254).
The measurement is calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction.
The GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/.