TITLE:   GCN CIRCULAR
NUMBER:  46101
SUBJECT: GRB 261029A: Liverpool Telescope observations
DATE:    26/10/29 22:44:59 GMT
FROM:    Dimple  at University of Birmingham <dimplepanchal96@gmail.com>


Dimple (U. Birmingham), D. O’Neill (U. Birmingham), A. Martin-Carrillo (UCD), D. B. Malesani (DAWN/NBI and Radboud) and B. P. Gompertz (U. Birmingham) report on behalf of a larger collaboration:

We have conducted observations of GRB 261029A, detected by SVOM/ECLAIRs (Goto et al., GCN 46072), with the IO:O optical camera on the 2-m robotic Liverpool Telescope in the u, g, r, i, and z filters starting on 2026-10-29 at 20:11:47 UT (0.790 days after the burst).
We clearly detected the afterglow (O'Neill et al., GCN 46073; He et al., GCN 46078; Wang et al., GCN 46079; De et al., GCN 46080; Cotter et al., GCN 46081; Sanchez Alvarez et al., GCN 46083; Yin et al., GCN 46084; Shi et al., GCN 46088; Kang et al., GCN 46090; Ma et al., GCN 46092; De et al., GCN 46093; Zhao et al., GCN 46099) with magnitude 20.37+/- 0.06 in r-band. 

Comparing our r-band magnitude with the previous observations, we estimate a temporal decay index of alpha ~ 1.4. The value is consistent with the late-time decay reported by Novotny et al. (GCN 46097).

Magnitudes are calibrated against nearby Pan-STARRS stars and are not corrected for Galactic extinction.