GCN Circular 38500
Subject
GRB 241209A: GRANDMA/TAROT upper limit
Date
2024-12-09T21:20:40Z (24 days ago)
From
marion.pillas@ligo.org
Via
Web form
M. Pillas (ULiege), S. Antier (OCA), O. Pyshna (Caltech), N. Guessoum (AUS), A. Klotz (IRAP), C. Andrade (UMN), M. Boer, C. Limonta (OCA), S. Karpov (FZU), M. Coughlin (UMN), , P. Hello (IJCLAB), P-A Duverne (APC), T. Pradier (Unistra/IPHC), D.Turpin (CEA-Saclay/Irfu), on behalf of the GRANDMA collaboration:
We observed the field of GRB 241209A, detected by Fermi/GBM (GCN 38474) and SWIFT/BAT (GCN 38476) using TAROT,/TCA and TCH. Observations began 3.5 min after Swift/T0 for TCA and 3.7 minutes after the trigger for TCH and both without a filter and continue up to 180 min after T0.
Weather was not great at TCA with an upper limit of 16 mag in r-mag of the image.
We did not detect any optical afterglow candidate with TCH to an upper limit of 19 mag in r and from T0+3 min to T0+6.1min within a circle of 6 arcmin radius centered on the most updated Swift/XRT source location (GCN 38486).
It is consistent with GOTO's report (GCN 38481) and VLT's report (GCN 38484).
All the data have been reduced by a single data processing pipeline, STDPipe (Karpov et al., 2022).
GRANDMA is a worldwide telescope network (grandma.ijclab.in2p3.fr) devoted to the observation of transients in the context of multi-messenger astrophysics (Antier et al. 2020 MNRAS 497, 5518). Kilonova-Catcher (KNC) is the citizen science program of GRANDMA (http://kilonovacatcher.in2p3.fr/).