TITLE:   GCN CIRCULAR
NUMBER:  19095
SUBJECT: IPN Triangulation of GRB 160225B
DATE:    16/02/26 21:45:56 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

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

K. Hurley, on behalf of the IPN,

V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa,
and A. Goldstein, 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, and

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

The long-duration GRB 160225B has been detected by Fermi (GBM; trigger 
478121069), Konus-Wind, INTEGRAL (SPI-ACS), Swift (BAT), so far, at 
about 69865 s UT (19:24:25). The burst was outside the coded field of 
view of the BAT.

We have triangulated it to a preliminary annulus centered
at RA(2000)=174.671 deg (11h 38m 41s)  Dec(2000)=+0.848 deg (+0d 50' 
52"), whose radius is 43.602 +/- 8.004 deg (3 sigma). The minimum 
distance between the center line of this annulus and the MASTER-NET 
optical transient (Buckley, et al., GCN Circ. 19092 and 19094) is 19.5 
arcmin, so the association of the OT and the GRB cannot be ruled out 
based on the triangulation only.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB160225_T69916/IPN/

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