GCN Circular 44865
Subject
GRB 260604C: GRANDMA further observations
Event
Date
2026-06-08T09:38:41Z (2 days ago)
Edited On
2026-06-08T10:03:18Z (2 days ago)
From
antier@ijclab.in2p3.fr
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of antier@ijclab.in2p3.fr
Via
Web form
O. Burkhonov (UBAI), M. Pillas (IAP), T. Leandro de Almeida (LNA), E. Elhosseiny (NRIAG), N. Kochiashvili (AbAO), L. Chen (TSU), A. Simon (TShNU of Kyiv), S. Antier (IJCLAB), M. Coughlin (UMN), S. Ehgamberdiev (UBAI), Y. Rajabov (UBAI), Y. Tillayev (UBAI), N. Sasaki (UEA,LNA), T. Kvernadze (AbAO), A. Takey (NRIAG), W. Corradi (LNA), I. Abdusamatjan (TNOT) on behalf of GRANDMA:
We conducted further follow-up observations of GRB 260604C (Fermi Team, GCN Circ. 44822, Gotz et al., GCN Circ. 44823) with GRANDMA up to now.
We observed a possible re-brightening in r, i, and R thanks to further observations from Two-meter Twin Telescope (TTT) sited at the Teide Observatory, UBAI-AZT-22 at Madainak Observatory, AbAO-T1.5m at Abastumani Observatory, KAO-1.88m at Kottamia Astronomical Observatory, and OPD-1.6m at Observatório do Pico dos Dias (Sasaki et al GCN 44857). This is shown in the public site group of the public ACME service Skyportal/ICARE https://skyportal-icare.ijclab.in2p3.fr/source/GCN-260604_202037. To access, one simply needs to create an account using your ORCID id.
Our measurements are aligned with Mondy's report (Pankov GCN 44862).
The observations are performed under the P7 campaign of GRANDMA to monitor SVOM alerts and LSST alerts from explosive fast transients filtered by BOOM/Babamul and FINK.
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 (kilonovacatcher.in2p3.fr). Astrophysics Center for Multimessenger studies in Europe is supported Skyportal/ICARE (contact camille.douzet@ijclab.in2p3.fr, skyportal.io). The TTT Observing Time Rights (DTO) used were provided by Light Bridges, SL.