GRB 080204

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks
on behalf of the Konus-Wind team,

K. Hurley and T. Cline on behalf of the Mars Odyssey, Konus,
and MESSENGER GRB teams,

W. Boynton, C. Fellows, K. Harshman, C. Shinohara and R. Starr, on
behalf of the GRS-Odyssey GRB team,

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,

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

A. von Kienlin, G. Lichti, and A. Rau, on behalf of the
INTEGRAL SPI-ACS GRB team,

M. Marisaldi, F. Fuschino, M. Galli, C. Labanti,
E. Del Monte, F. Lazzarotto, L. Pacciani, P. Soffitta
on behalf of the AGILE team, and

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

Mars Odyssey (GRS), Konus-Wind, Suzaku-WAM, INTEGRAL SPI-ACS,
AGILE-MCAL, SuperAGILE, and Swift-BAT observed the long-duration, hard 
spectrum GRB 080204 at about 50192 s UT (13:56:32). The burst was 
outside the coded field of view of the BAT and SuperAGILE.
The burst light curve shows a short precursor, followed in ~3 sec by a 
single multipeaked pulse with a duration of ~15 sec. There is a sign of 
extended emission seen up to T-T0~80 s in the Konus-Wind soft band.

We have triangulated the burst to the following, preliminary 3-sigma
error box:
-----------------------------------------------
    RA(2000), deg             Dec(2000), deg
-----------------------------------------------
Center:
  285.566 (19h 02m 16s)   -62.896 (-62d 53' 44")
Corners:
  287.728 (19h 10m 55s)   -62.334 (-62d 20' 01")
  283.813 (18h 55m 15s)   -63.453 (-63d 27' 12")
  283.277 (18h 53m 07s)   -63.402 (-63d 24' 08")
  287.212 (19h 08m 51s)   -62.305 (-62d 18' 18")
-----------------------------------------------

The error box area is 1212 sq. arcmin.
This error box may be improved

Preliminary analysis of the Konus-Wind data yields
a burst fluence of ~4x10^-5 erg/cm2 (in the 20 keV - 4 MeV range),
and a very hard energy spectrum with an Epeak of the main pulse
of ~1.4 MeV.

Detailed spectral parameters will be reported later.

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

The long hard GRB 080204 (Golenetskii et al., GCN 7256
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triggered Konus-Wind at T0=50190.835 (13:56:30.835).

As observed by Konus-Wind the burst
had a fluence of 2.65(-0.47, +0.37)x10^-5 erg/cm2,
and a 64-ms peak flux measured from T0-0.032 s
of 9.52(-2.49, +2.25)x10^-6 erg/cm2/s
(both in the 20 keV - 6 MeV energy range).

The time-integrated spectrum of the burst
(not including the precursor; from T0 to T0+16.640 s)
is well fitted (in the 20 keV - 6 MeV range)
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -1.35(-0.09, +0.06)
and Ep = 1279(-382, +469) keV (chi2 = 79.2/78 dof).

All the quoted errors are at the 90% confidence level.

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.rssi.ru/LEA/GRBs/GRB080204_T50190/

Y. Terada, K. Onda, M. Tashiro, Y. Urata, A. Endo,
M. Suzuki, N. Kodaka, K. Morigami (Saitama U.),
M. Ohno, T. Uehara, T. Takahashi, Y. Fukazawa,
C. Kira, Y. Hanabata (Hiroshima U.), T. Tamagawa (RIKEN),
K. Yamaoka, Y. E. Nakagawa, S. Sugita (Aoyama Gakuin U.),
T. Enoto, R. Miyawaki, K. Nakazawa, K. Makishima (Univ. of Tokyo),
E. Sonoda, M.Yamauchi, H. Tanaka, R. Hara (Univ. of Miyazaki),
M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA), S. Hong (Nihon U.),
on behalf of the Suzaku WAM team, report:

The IPN localized GRB 080204 (Golenetskii et al., GCN 7256
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triggered the Suzaku Wide-band  All-sky Monitor (WAM) which covers
an energy range of 50 keV - 5 MeV at 13:56:32 UT (=T0).
The observed light curve shows a multi-peaked structure,
starting at T0-1s, ending at T0+10s, with a duration (T90) of about
4.8seconds. The fluence in 100 - 1000 keV was 1.0(+0.1,-0.1)x10^-5
erg/cm^2. The 1-s peak flux measured from T0+3s was
3.9(+0.2,-0.9)photons/cm2/s in the same energy range.

Preliminary result shows that the time-averaged spectrum from
T0+0s to T0+10s is well fitted by a power-law with exponential cutoff model:
    dN/dE ~  E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
    alpha       0.8(+0.2,-0.3), and
    Epeak       990(+350,-205) keV (chi^2/d.o.f. = 25.0/24).

All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

The light curves for this burst are available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html