[vsnet-grb-info 10146] IPN triangulation of GRB 110120A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  11595
SUBJECT: IPN triangulation of GRB 110120A
DATE:    11/01/23 00:07:18 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val at mail.ioffe.ru>

K. Hurley and J. Goldsten, on behalf of the MESSENGER NS GRB team,

S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and
T. Cline, on behalf of the Konus-Wind team,

V. Connaughton, M. Briggs, and C. Meegan, on behalf of the Fermi GBM team,

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

and

K. Yamaoka, M. Ohno, Y. Hanabata, Y. Fukazawa, T. Takahashi, M. Tashiro,
Y. Terada, T. Murakami, and K. Makishima, on behalf of the Suzaku WAM
team, report:

Fermi (GBM), Konus-Wind, Swift (BAT), MESSENGER (GRNS), and Suzaku (WAM) 
observed the long, hard GRB 110120A at about 15:59:39 UT (Fermi/GBM 
trigger 317231981: Lin, GCN 11591). The burst was outside the coded 
field of view of the BAT.

We have triangulated it to a 3 sigma error box whose coordinates are:
-----------------------------------------------
    RA(2000), deg              Dec(2000), deg
-----------------------------------------------
Center:
   60.481 (04h 01m 55s)   -10.548 (-10d 32' 51")
Corners:
   56.433 (03h 45m 44s)    -5.247 (-05d 14' 48")
   62.714 (04h 10m 51s)   -13.354 (-13d 21' 16")
   64.578 (04h 18m 19s)   -14.953 (-14d 57' 11")
   58.278 (03h 53m 07s)    -7.456 (-07d 27' 21")
-----------------------------------------------
The error box area is 2.548 sq. deg.
This error box may be improved.
Because the Earth, the Wind, and the MESSENGER satellites are nearly 
aligned at the moment (the angular distance between Wind and MESSENGER 
is only 5.7 deg), the annuli intersect at grazing incidence and the 
resulting 3-sigma box is long.

A map is posted at http://www.ioffe.ru/LEA/GRBs/GRB110120_T57582/IPN/
showing the GBM best-fit position (blue star and circle), the IPN annuli 
(solid lines with centers dot-dashed), and the box (solid black closed 
polyline).