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GCN Circular 31649

IPN triangulation of GRB 220222A
2022-02-25T12:51:38Z (2 years ago)
Anna Ridnaia at Ioffe Institute <>
A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin
on behalf of the HEND/Mars-Odyssey team,

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

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
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, and

W. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr,
and A.S. Gardner on on behalf of the GRS-Odyssey GRB team,

The long-duration GRB 220222A
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 31630;
Swift/BAT-GUANO detection: Tohuvavohu et al., GCN Circ. 31633)
has been detected by Fermi (GBM trigger 667189282), Konus-Wind,
Swift (BAT), and Mars-Odyssey (HEND), so far,
at about 8477 s UT (02:21:17).
The burst was outside the coded field of view of the BAT.

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
  RA(2000), deg                 Dec(2000), deg
   32.630 (02h 10m 31s) -14.008 (-14d 00' 31")
   38.241 (02h 32m 58s) -24.843 (-24d 50' 33")
   38.323 (02h 33m 18s) -25.232 (-25d 13' 56")
   24.966 (01h 39m 52s)  +3.526 ( +3d 31' 33")
   24.595 (01h 38m 23s)  +4.715 ( +4d 42' 55")
The error box area is 3.6 sq. deg, and its maximum
dimension is 32.8 deg (the minimum one is 6.7 arcmin).
The Sun distance was 51 deg.

This box may be improved.

The IPN localization is consistent with, but reduces the area of, the
Fermi GBM Final Real-time localization (GCN Circ. 31630).

A triangulation map and HEALPix FITS file are posted at

The time history and spectrum will be given in forthcoming
GCN Circulars.

This GCN is the corrected version of GCN 31645.
We apologize for any confusion this may have caused.
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