TITLE:   GCN CIRCULAR
NUMBER:  37455
SUBJECT: IPN triangulation of GRB 240905B (short)
DATE:    24/09/11 15:24:31 GMT
FROM:    Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>

A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin
on behalf of the MGNS/BepiColombo team,

J. Benkhoff on behalf of the BepiColombo team,

D. Svinkin, D. Frederiks, A. Ridnaia, A. Lysenko,
and T. Cline on behalf of the Konus-Wind team,

A. Goldstein, M. S. Briggs, C. Wilson-Hodge,
and E. Burns on behalf of the Fermi GBM team,

E. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,

and

G. Waratkar, V. Jethwani, J.Joshi, V. Bhalerao, D. Bhattacharya,
and S. Vadawale, on behalf of the Astrosat-CZTI team, report:

The short-duration GRB 240905B
(Fermi-GBM detection: The Fermi GBM team, GCN 37389;
Dalessi et al., GCN 37436;
AstroSat-CZTI detection: Joshi et al., GCN 37391;
Fermi-LAT detection: Gupta et al., GCN 37418)
was detected by Fermi (GBM and LAT), Konus-Wind, INTEGRAL (SPI-ACS),
Astrosat (CZTI), and BepiColombo (MGNS) at about 16036 s UT (04:27:16).

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
---------------------------------------------
  RA(2000), deg                 Dec(2000), deg
 ---------------------------------------------
 Center:
  267.922 (17h 51m 41s) +14.240 (+14d 14' 24")
 Corners:
  267.264 (17h 49m 03s) +12.544 (+12d 32' 40")
  267.181 (17h 48m 43s) +12.565 (+12d 33' 54")
  268.618 (17h 54m 28s) +15.927 (+15d 55' 37")
  268.703 (17h 54m 49s) +15.906 (+15d 54' 21")
 ---------------------------------------------
The error box area is 1087 sq. arcmin, and its maximum
dimension is 3.65 deg (the minimum one is 5 arcmin).
The Sun distance was 100 deg.

This localization may be improved.

The IPN localization is consistent with, but reduces the area of,
the Fermi-LAT localization.

Swift-XRT reported six afterglow candidates for this burst (Source 1-6, Brivio et. al.,  GCN 37421). Three candidates (Sources 1, 2, and 6) are inside the IPN box.

A triangulation map and HEALPix FITS file are posted at
http://www.ioffe.ru/LEA/GRBs/GRB240905_T16038/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.