[vsnet-grb-info 25427] IPN Triangulation of a bright burst from SGR 1935+2154

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27527
SUBJECT: IPN Triangulation of a bright burst from SGR 1935+2154
DATE:    20/04/10 16:45:02 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin at mail.ioffe.ru>

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Ridnaia,
and T. Cline on behalf of the Konus-Wind team,

K. Hurley, on behalf of the IPN, and

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

A bright, short-duration, soft burst has been observed by
Fermi (GBM trigger 608204639) and Konus-Wind,
so far, at about 35034 s UT (09:43:54) on April 10.

We have triangulated it to a Konus-GBM annulus centered at
RA(2000)=355.993 deg (23h 43m 58s) Dec(2000)=-0.325 deg (+0d 19' 31"),
whose radius is 64.478 +/- 0.078 deg (3 sigma).

This localization may be improved.

The position of SGR 1935+2154 is inside the annulus
at 4.2 arcmin from its center line.

Given the positional coincidence of this burst with SGR 1935+2154,
its time history, and softness of its spectrum (as observed by Konus-
Wind and Fermi-GBM), we conclude this burst is likely originated from
SGR 1935+2154.

A triangulation map is posted at
http://www.ioffe.ru/LEA/SGRs/200410_T35032/IPN/

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