TITLE:   GCN CIRCULAR
NUMBER:  39588
SUBJECT: IPN triangulation of GRB 250222A
DATE:    25/03/04 12:59:51 GMT
FROM:    Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>

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

Y. Zhang, C. Wang, S. Xiong, J. Wei, and B. Cordier
on behalf of the SVOM-GRM team,

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

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

S. Barthelmy, J. Cummings, H. Krimm, D. Palmer, and A. Tohuvavohu
on behalf of the Swift-BAT team, report:

The long-duration GRB 250222A
(SVOM-GRM detection: Wang et al., GCN 39454)
was detected by SVOM (GRM), Konus-Wind, and INTEGRAL (SPI-ACS)
at about 51859 s UT (14:24:19).

Fermi (GBM) and Swift (BAT) were taking data, but shows 
no rate increase at the burst time.

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
 ---------------------------------------------
  RA(2000), deg                 Dec(2000), deg
 ---------------------------------------------
 Center:
  359.336 (23h 57m 21s)  +0.946 ( +0d 56' 47")
 Corners:
  335.308 (22h 21m 14s) +25.783 (+25d 47' 00")
  352.637 (23h 30m 33s) +12.776 (+12d 46' 35")
    6.156 (00h 24m 37s) -19.368 (-19d 22' 04")
    2.915 (00h 11m 40s)  -9.794 ( -9d 47' 40")
 ---------------------------------------------
The error box area is 38.5 sq. deg, and its maximum
dimension is 54 deg (the minimum one is 3 deg).
The Sun distance was 25 deg.

This localization may be improved.

The SVOM (GRM) localization (GCN 39454) is inconsistent with 
the IPN localization and also with burst non-detection by Fermi (GBM) and Swift (BAT).

A triangulation map and HEALPix FITS file are posted at
http://www.ioffe.ru/LEA/GRBs/GRB250222_T51862/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.