GRB 070626

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

K. Hurley, J. Goldsten, D. M. Smith, R. P. Lin, J. McTiernan, R. 
Schwartz, C. Wigger, W. Hajdas, and A. Zehnder, on behalf of the 
MESSENGER and RHESSI GRB teams,

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

A very long, bright GRB triggered Konus-Wind at 2007-06-26
T0=14850.883 s UT (04:07:30.883). It was also observed by Suzaku-WAM, 
RHESSI and the MESSENGER neutron spectrometer, which also serves as a 
GRB detector.

The burst started at T-T0 ~-120 s and ended at T-T0 ~210 sec.
The Earth-crossing time of the onset was 14733 s UT (04:05:33).
The burst light curve shows several multipeaked pulses.

We have triangulated it to a 3 sigma error box whose coordinates are:

-----------------------------------------------
    RA(2000)                    Dec(2000)
-----------------------------------------------
Center:
  141.355 (09h 25m 25s)   -39.865 (-39d 51' 54")
Corners:
  139.529 (09h 18m 07s)   -39.872 (-39d 52' 20")
  142.903 (09h 31m 37s)   -40.020 (-40d 01' 11")
  143.210 (09h 32m 50s)   -39.805 (-39d 48' 17")
  139.838 (09h 19m 21s)   -39.673 (-39d 40' 24")
-------------------------------------------------

The error box area is 2047 square arcminutes.
The box may be improved.

Preliminary analysis of the Konus-Wind data yields
a burst fluence of ~4x10^-4 erg/cm2 (in the 20 keV - 4 MeV range),
the spectrum of the main part of the burst (from T0 to T0+190 s)
can be fitted (in the 20 keV - 4 MeV range)
by GRBM (Band) model for which:
the low-energy photon index is alpha = -1.5,
the high energy photon index beta = -2.3,
the peak energy Ep = 240 keV.

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.rssi.ru/LEA/GRBs/GRB070626_T14850/

Detailed spectral parameters will be reported later.

Y. Terada, T. Tamagawa (RIKEN), M. Ohno, T. Uehara, T. Takahashi, 
Y. Fukazawa, C. Kira (Hiroshima U.), K. Yamaoka, Y. E. Nakagawa, 
S. Sugita (Aoyama Gakuin U.), K. Morigami, N. Kodaka, K. Onda, 
M. Tashiro, M. Suzuki, Y. Urata, A. Endo (Saitama U.), T. Enoto, 
R. Miyawaki, K. Nakazawa, K. Makishima (Univ. of Tokyo), E. Sonoda, 
M. Yamauchi, S. Maeno, 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 long burst, GRB 070626 (S. Golenetskii et al. GCN 6592
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 ) was
detected at 2007-06-26 04:07:30 UT (= T0) with the Suzaku Wide-band All-sky
Monitor (WAM), which covers an energy range of 50 keV - 5 MeV. The burst
continues from T= T0-120 sec to T0+210 sec, as already reported on GCN
6592
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 . The object position reported by GCN 6592
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  corresponds to the
incident angle of (theta, phi) = (103 deg, 169 deg) to the HXD WAM,
where the energy response is well calibrated. 
The fluence in the 100 -- 1000 keV energy band was 2.25(+- 0.01) x
10^-4 erg/cm2, and the 1-sec peak flux was 19.5 +/- 0.2 photons/cm^2/sec 
in the same energy range.

According to preliminary analyses, the time averaged spectrum from T0
to T0+190 sec in the 120 keV to 2.0 MeV energy band can be reproduced by 
the Band function (Band et al. 1993, ApJ 413, p281) with the following 
parameters;
  alpha = -1.55 +/- 0.05, 
  beta  = -2.15 +/- 0.05, and
  Epeak =   600 +/- 50 keV.

All the quoted errors are at the 90% confidence level, while systematic 
errors are not included. Since the on-board trigger system was disabled 
at the time of T0, no BST mode data with a time resolution of 15.625
msec is available, and the spectral analyses were performed by the 
continuous monitoring (TRN) data with the 1 sec resolution.

The light curve data with 1 sec resolution will be appeared at the web site 
 http://www.astro.isas.ac.jp/suzaku/HXD-WAM/WAM-GRB/grb/untrig/grb_table.html

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

We report further analysis of the bright long GRB 070626
localized by IPN (Golenetskii  et al., GCN 6592
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 ).

As observed by Konus-Wind the burst
had a fluence of 3.91(-0.13, +0.16)x10^-4 erg/cm2,
and a 64-ms peak flux measured from T0+73.216 s
1.94(-0.16, +0.20)x10^-5 erg/cm2/s
(both in the 20 keV - 4 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+187.905 s: this interval comprises ~93%
of the burst total counts) can be fitted
(in the 20 keV - 4 MeV range)
by GRBM (Band) model for which:
the low-energy photon index is alpha = -1.45 (-0.03, +0.04),
the high energy photon index beta = -2.28 (-0.12, +0.08),
the peak energy Ep = 226 (-17, +19) keV (chi2 = 79/68 dof).

The spectrum of the burst maximum
(accumulated from T0+72.192 s to T0+74.752 s)
is well fitted (in the 20 keV - 4 MeV range)
by GRBM (Band) model for which:
the low-energy photon index is alpha = -1.27 (-0.07, +0.08),
the high energy photon index beta = -2.51 (-0.88, +0.27),
the peak energy Ep = 355 (-62, +69) keV (chi2 = 77/69 dof).

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