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GCN Circular 8646

Subject
IPN triangulation of short hard GRB 081209
Date
2008-12-10T16:36:58Z (15 years ago)
From
Valentin Pal'shin at Ioffe Inst <val@mail.ioffe.ru>
S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and K. 
Hurley on behalf of the Konus-Wind team,

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

M. Marisaldi, F. Fuschino, E. Del Monte, Y. Evangelista, I. Lapshov, M. 
Rapisarda, and A. Giuliani, on behalf of the AGILE Team,
report:

AGILE-MCAL, Swift-BAT, and Konus-Wind observed the short-duration hard 
spectrum GRB 081209 at about 23:31:56 UT (corresponds to the Fermi/GBM 
trigger 250558317). The burst was outside the coded field of view of the 
BAT and SuperAGILE. The burst light curve shows a single peak with a 
duration of ~0.2 sec.

Triangulation gives an annulus centered at RA(2000)=77.269 (05h 09m 05s) 
  Dec(2000)=+17.346 (+17d 20' 47"), whose radius is 48.435 +/- 0.181 deg 
(3sigma).  This intersects the GBM error circle (the Fermi-GBM ground 
position is RA(2000), Dec(2000) = 88.980d (+05h 55m 55s), +71.450d (+71d 
27' 00")) assuming its 3sigma uncertainty of 11.8 deg (7.8deg stat + 
3deg syst)) to form a long 3sigma error box whose corners are at
-------------------------------------------------
        RA(2000)                 Dec(2000)
-------------------------------------------------
  104.995 (06h 59m 59s)   +61.438 (+61d 26' 16")
  105.760 (07h 03m 02s)   +61.616 (+61d 36' 58")
   62.128 (04h 08m 31s)   +64.879 (+64d 52' 43")
   62.813 (04h 11m 15s)   +64.597 (+64d 35' 47") 
--------------------------------------------------

This error box may be improved.

Preliminary analysis of the Konus-Wind data yields
a burst fluence of ~2x10^-6 erg/cm2 (in the 20 keV - 3 MeV range),
and an Epeak of the time-integrated spectrum of ~1 MeV.

Detailed spectral parameters will be reported later.

The K-W light curve of this GRB and IPN triangulation map is
available at http://www.ioffe.ru/LEA/GRBs/GRB081209_T84720/
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