GCN Circular 39090
Subject
GRB 250129A: KAIT optical observations of the rebrightening around 5.1 hours
Event
Date
2025-01-29T22:21:18Z (a year ago)
From
Weikang Zheng at UC Berkeley <weikang@berkeley.edu>
Via
email
WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on
behalf of the KAIT GRB team:
The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located
at Lick Observatory, responded to GRB 250129A detected by Swift
(Beardmore et al., GCN 39066) starting at 09:25 UT, ~4.68h after
the bust. Observations were performed in the clear (roughly R)
filter with a set of 60s exposures and lasted for ~2.2h. The
optical afterglow (Francile et al., GCN 39065; Beardmore et al.,
GCN 39066; Schneider et al., GCN 39071; Belkin et al., GCN 39072;
Izzo et al., GCN 39073; Izzo & Malesani, GCN 39074; Gosh et al.,
GCN 39077; Schneider et al., GCN 39078; Brivio et al., GCN 39079;
Siegel et al., GCN 39085) was clearly detected in every individual
image. Our photometry results show that the OT rebrightened since
~4.68h (~16.7 mag) and reached a double peak at ~4.99h (~16.3 mag)
and again at 5.2h (~16.3 mag), then decayed afterword, with small
flares during decay phase, till ~17.1 mag at ~6.90h.