GCN Circular 46159

Subject
IPN triangulation of GRB 261029C (short / bright)
Event
GRB 261029C
Date
2026-11-05T14:05:32Z (a day ago)
From
Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>
Via
Web form
D. Svinkin, D. Frederiks, A. Lysenko, V. Panteleeva, A. Ridnaia,
and T. Cline on behalf of the Konus-Wind team,

E. Burns on behalf of the IPN,

D.J. Lawrence, J.O. Goldsten, P.N. Peplowski 
on behalf of the Psyche/GRNS team,

A. Arya (IITB), G. Waratkar (Caltech/IITB), V. Bhalerao (IITB),
on behalf of the Astrosat-CZTI team,

and

C. Wang (IHEP), S. Xiong (IHEP), S. Zhang (IHEP), J. Wei (NAOC),
and B. Cordier (CEA) on behalf of the SVOM-GRM team, report:

The bright, short-duration GRB 261024C
(AstroSat-CZTI detection: Harsha et al., GCN 46129Loading...
 
 )
was detected by SVOM (GRM), Konus-Wind, AstroSat (CZTI),
and Psyche (GRNS) at about 85117 s UT (23:38:37).

We have triangulated it to two preliminary, 3 sigma error boxes
whose coordinates are:

Box 1:
 ---------------------------------------------
  RA(2000), deg                 Dec(2000), deg
 ---------------------------------------------
 Center:
  336.252 (22h 25m 01s)  -1.683 ( -1d 41' 00")
 Corners:
  336.366 (22h 25m 28s)  -2.174 ( -2d 10' 27")
  335.918 (22h 23m 40s)  -0.938 ( +0d 56' 16")
  336.151 (22h 24m 36s)  -1.225 ( -1d 13' 30")
  336.633 (22h 26m 32s)  -2.551 ( -2d 33' 02")
 ---------------------------------------------

Box 2:
 ---------------------------------------------
  RA(2000), deg                 Dec(2000), deg
 ---------------------------------------------
 Center:
  340.324 (22h 41m 18s) -12.314 (-12d 18' 52")
 Corners:
  340.077 (22h 40m 19s) -11.872 (-11d 52' 20")
  340.577 (22h 42m 19s) -13.093 (-13d 05' 35")
  340.559 (22h 42m 14s) -12.724 (-12d 43' 26")
  340.025 (22h 40m 06s) -11.414 (-11d 24' 50")
 ---------------------------------------------
The area of each error box is 596 sq. arcmin, and their maximum
dimension is 1.76 deg (the minimum one is 7.3 arcmin).
The Sun distance for each box was ~120 deg.

This localization may be improved.

A triangulation map and HEALPix FITS files are posted at
http://www.ioffe.ru/LEA/GRBs/GRB261029_T85117/IPN/
The HEALPix triangulation map is the multi-order HEALPix in units of probability density.

The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular.