TITLE:   GCN CIRCULAR
NUMBER:  24095
SUBJECT: IPN triangulation of GRB 190409B (short)
DATE:    19/04/11 00:15:09 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin and K. Hurley, on behalf of the IPN,

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

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,

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

The short-duration GRB 190409B was detected
by Fermi (GBM trigger 576538690), INTEGRAL (SPI-ACS),
and Swift (BAT), at about 77885 s UT (21:38:05).
The burst was outside the coded field of view of the BAT.

We have triangulated this GRB to a GBM-INTEGRAL annulus centered at 
RA(2000)=258.187 deg (17h 12m 45s) Dec(2000)=+48.305 deg (+48d 18' 19"), 
whose radius is 89.659(-6.155,+2.958) deg (3 sigma).

The annulus reduces the area of the 2 sigma Fermi-GBM final position
(glg_healpix_all_bn190409901_v00) by about a factor of 5.

This annulus may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB190409_T77885/IPN