GCN Circular 44927
A. Bochenek, D. A. Perley (LJMU), report:
We observed the field of the optical counterpart (O'Neil et al., GCN 44903) of GRB 260610b (Fu et al., GCN 44901) using the IO:O optical camera on the 2m robotic Liverpool Telescope. We obtained 5x120s exposures in SDSS griz filters, starting at 2026-06-10 23:39:02 UT, approximately 23.9 hours after trigger.
We detect a source in the stacked images in all filters at the position reported by O'Neil et al. (GCN 44903), observed also by Watson et al. (GCN 44905); Zhu et al. (GCN 44909); Gillanders et al. (GCN 44910); Akl et al. (GCN 44911); O'Neill et al. (GCN 44914); Moskvitin et al. (GCN 44918); Jackson-Horne et al. (GCN 44919); Izzo, (GCN 44920), and Li et al. (GCN 44921). The photometry is:
| MJD (mid) | T_mid-T_0 | Filter | Mag. (AB) |
|---|---|---|---|
| 61202.98947 | 23.98 h | r | 20.22 ± 0.02 |
| 61202.99795 | 24.18 h | i | 19.89 ± 0.02 |
| 61203.00646 | 24.38 h | z | 19.78 ± 0.05 |
| 61203.01493 | 24.59 h | g | 20.66 ± 0.03 |
The photometry is in the AB magnitude system, was calibrated using nearby PanSTARRS secondary standards and was not corrected for extinction.