GCN Circular 44276
Subject
GRB 260412A: SVOM detection of a long burst
Event
Date
2026-04-12T06:57:17Z (a day ago)
From
SVOM_group <svomgroup@bao.ac.cn>
Via
Web form
Ziqi Wang (GXU), Zhiyong Liu(GZNU), Hatsune GOTO(RIKEN), Wenjin XIE(NAOC), Ulysse Jacob (LUPM)
report on behalf of the SVOM mission team:
At 2026-04-12T06:13:46 UTC (T0), SVOM/ECLAIRs triggered and located the gamma-ray burst GRB 260412A (SVOM burst-id sb26041206), which is also detected by Fermi/GBM (Fermi GBM Team, GCN 44275).
The following trigger information was received on the ground with low latency by the SVOM VHF Alert Network.
The burst was detected both by the Count-Rate Trigger (CRT) and the Image Trigger (IMT), which produced a sequence of 67 alerts. IMT provided the alert with the best signal-to-noise-ratio in the image (SNR) of 42.64 in the [8-120] keV energy band over a time window of 81.92 seconds starting at 2026-04-12T06:13:35.
The localization of the best alert is R.A., Dec. 79.9074, -44.5851 degrees:
R.A. (J2000) = 5h19m37.78s
Dec. (J2000) = -44d35m06.31s
with a 90% confidence level (C.L.) radius of 2.69 arcmin (including systematic error of 2 arcmin added in quadrature).
The SVOM/ECLAIRs preview VHF light curve showed multiple broad peak structures with a T90 duration of about 321.20 (-2.00 +1.89) s in the 5-120 keV energy band.
Due to SVOM performing another ToO-EX during the trigger, no immediate slew was performed on this burst.
No X-ray observation could be performed by SVOM/MXT for the time being.No optical observation could be performed by SVOM/VT for the time being.
The Space-based multi-band astronomical Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA), French Space Agency (CNES), and the Chinese Academy of Sciences (CAS), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. SVOM/ECLAIRs was developed jointly by CNES, CEA-IRFU, CNRS-IRAP, CNRS-APC. SVOM/GRM was developed by the Institute of High Energy Physics (IHEP) of CAS. SVOM/MXT was developed jointly by CNES, CEA-IRFU, CNRS-IJCLab, University of Leicester, MPE.
The Burst Advocate (BA) on shift for this alert is Ziqi Wang: ziqi.wang@st.gxu.edu.cn.
Please contact the BA by email if you require additional information.