GRB 040810

P.A. Price (IfA, University of Hawaii), M. Hauser (Landessternwarte
Heidelberg-K\"onigstuhl), G. P\uhlhofer (MPIK) and S.J. Wagner
(Landessternwarte Heidelberg-K\"onigstuhl) report:

We observed a small number (4) of 18 arcmin square fields within the
error box of GRB 040810 (HETE #3489/4) using the 40-inch telescope at
Siding Spring Observatory in R-band at mean epoch 2004 Aug 10.761,
before other time-sensitive observations became of high priority.  These
fields are centered at J2000 coordinates: 23:52:00 -35:04:25 ; 23:52:00
-34:49:22 ; 23:53:30 -35:11:55 ; 23:54:31 -34:56:54.

We do not identify any optical afterglow upon manual comparison with the
Digitised Sky Survey 2 F plates.  We estimate that the limiting
magnitude of these observations are R ~ 18 mag from rough calibration
with the USNO-A2.0 catalogue.

This message may be cited.

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

Konus-Wind detected the intense multipeak
GRB 040810 (=H3489) at 14:15:43.177 s UT.

As observed by Konus-Wind, this burst had a duration of 124s,
a 20-2000 keV fluence of ~1.4E-4 erg/cm2,
a 20-2000 keV peak flux ~1.0E-5 erg/cm2 s over 0.256 s,
Epeak for time-integrated spectrum 206 +/- 11 keV,
Epeak at maximum intensity 450 +/- 45  keV.

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

I. Mitrofanov, S. Charyshnikov, V. Grinkov, A. Kozyrev, M. Litvak, and
A. Sanin, on behalf of the HEND-Odyssey GRB team,

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

E. Mazets and S. Golenetskii, on behalf of the Konus-Wind GRB team,

G. Ricker, J-L Atteia, N. Kawai, D. Lamb, S. Woosley, J. Doty, R.
Vanderspek, J. Villasenor, G. Crew, N. Butler, J.G.  Jernigan, F.
Martel, G. Prigozhin, A. Dullighan, J. Braga, R.  Manchanda, G.
Pizzichini, Y.  Shirasaki, C. Graziani, M. Matsuoka, T.  Tamagawa, T.
Sakamoto, A.  Yoshida, E. Fenimore, M. Galassi, T.  Donaghy, C.
Barraud, M. Boer, J-F Olive, and J-P Dezalay, on behalf of the HETE GRB
team,

D. M. Smith, R. P. Lin, J. McTiernan, R. Schwartz, C. Wigger, W.
Hajdas, and A. Zehnder, on behalf of the RHESSI GRB team, report:

Mars Odyssey (HEND), Konus-Wind, HETE (FREGATE and WXM), and RHESSI
observed this burst.  Ulysses was off.  HETE Ground Analysis produced
two error circles for it, distributed as GCN Notices Sequence 3 and 4.
The burst occurred after HETE sunrise, at orbital phase=0.78, just as
the science instruments were being shut off; as a result, HETE observed
only the precursor to this long, intense event (GCN 2641
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 , Aptekar et
al.).  The HETE star trackers were also off at the time of the burst,
so spacecraft aspect could only be established crudely using the
spacecraft sun sensors.


We have triangulated this burst to two annuli, whose coordinates are
RA, Decl = 332.624, -12.452 degrees, with radius 34.105 +/-0.014
degrees, and RA, Decl = 309.285, -21.748 degrees, with radius 46.199
+/- 1.815 degrees (3 sigma values).  These annuli intersect to form an
error box whose area is ~780 sq. arcmin., and whose corners are given
by:

RA	    Decl.
  2.438  -33.023
357.554  -38.402
  2.438  -32.967
357.562  -38.353

The larger of the two IPN annuli encompasses parts of both HETE
WXM error circles.  The smaller annulus, however, intersects the
larger WXM error circle in Sequence Number 3, but not the smaller
one given in Sequence Number 4.  The intersection forms an error
box whose area is ~90 sq. arcmin., and whose corners are given
by:

RA        Decl.
359.134  -36.959
359.716  -36.366
359.002  -37.043
359.788  -36.244

A map has been posted at ssl.berkeley.edu/ipn3/040810.