GRB 120603A

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

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

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

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo, and C.
Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB 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:

The short-duration GRB 120603A has been observed by Fermi (GBM: trigger
360412331), INTEGRAL (SPI-ACS), Konus-Wind, Suzaku (WAM), and MESSENGER
(GRNS), so far, at about 37930 s UT (10:32:10).

We have triangulated it to a preliminary, 3 sigma error box whose
coordinates are:
---------------------------------------------
    RA(2000), deg                 Dec(2000), deg
   ---------------------------------------------
   Center:
    198.794 (13h 15m 11s)  +4.326 ( +4d 19' 35")
   Corners:
    197.693 (13h 10m 46s)  +2.527 ( +2d 31' 36")
    199.766 (13h 19m 04s)  +6.230 ( +6d 13' 49")
    199.927 (13h 19m 42s)  +6.103 ( +6d 06' 12")
    197.853 (13h 11m 25s)  +2.399 ( +2d 23' 56")
   ---------------------------------------------

The error box area is 0.857 sq. deg, and its maximum
dimension is 4.280 deg.

This box may be improved.

The time history and spectrum will be given in a forthcoming GCN Circular.

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

The short-duration GRB 120603A
(IPN detection and localization: Golenetskii at al., GCN 13353
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triggered Konus-Wind at T0=37934.201s UT (10:32:14.201)

The light curve shows a single pulse with a total duration of ~0.3 s.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB120603_T37934/

As observed by Konus-Wind the burst
had a fluence of (1.0 � 0.1)x10-6 erg/cm2,
and a 64-ms peak flux, measured from T0-0.064,
of (6.2 � 1.1)x10-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

Since almost the whole of the emission is seen before the trigger,
no multichannel spectra are available for this burst.
Modelling the 3-channel time-integrated spectrum
(from T0-0.256 to T0) by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) yields
alpha = -0.4 � 0.2, and Ep = 560 � 60 keV.

All the quoted errors are estimated at the 1 sigma confidence level.

T. Yasuda, M. S. Tashiro, Y. Terada, W. Iwakiri, K. Takahara,
M. Asahina, S. Kobayashi, A. Sakamoto, H. Ueno (Saitama U.),
M. Akiyama, N. Ohmori, M. Yamauchi (Univ. of Miyazaki),
K. Yamaoka, Y. E. Nakagawa (Waseda U.),
Y. Hanabata, T. Kawano, K. Takaki, R. Nakamura, Y.Tanaka, M. Ohno,
Y. Fukazawa (Hiroshima U.), S. Sugita (Nagoya U.),
M. Kokubun, T. Takahashi (ISAS/JAXA),
Y. Urata, P. Tsai (NCU), K. Nakazawa, K. Makishima (Univ. of Tokyo),
on behalf of the Suzaku WAM team, report:


The IPN localized GRB 120603A (IPN; Golenetskii et al., GCN 13353
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 ,
Konus-Wind; Golenetskii et al., GCN 13354
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triggered the Suzaku Wide-band  All-sky Monitor (WAM) which covers an
energy range of 50 keV - 5 MeV at 2012-06-03 10:32:9.80 UT (=T0).

The observed light curve shows a single peak with a duration (T90) of 
about 0.19 seconds.
The fluence in 100 - 1000 keV was 5.49 (+1.15/-4.79) x10^-7 erg/cm^2.
The 1-s peak flux was 1.19 (+0.20/-0.94) photons/cm^2/s in the same
energy range.

Preliminary result shows that the time-averaged spectrum is well fitted 
by a power-law with exponential cutoff model:
dN/dE ~  E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
alpha       0.70 (+0.81/-1.17), and
Epeak       580 (+285/-203) keV (chi^2/d.o.f. = 16/14).

All the quoted errors are at statistical 90% confidence level

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