TITLE: GCN GRB OBSERVATION REPORT NUMBER: 5005 SUBJECT: GRB 060425: IPN localization and KW spectrum of a short, hard burst DATE: 06/04/26 23:50:41 GMT FROM: Jay R. Cummings at NASA/GSFC/Swift J. Cummings, S. Barthelmy, N. Gehrels, and H. Krimm, on behalf of the Swift-BAT team, S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and T. Cline on behalf of the Konus-Wind team, A. von Kienlin, G. Lichti, A. Rau, D. Gotz, and S. Mereghetti, on behalf of the INTEGRAL GRB team, K. Hurley, D. M. Smith, R. P. Lin, J. McTiernan, R. Schwartz, C. Wigger, W. Hajdas, and A. Zehnder, on behalf of the RHESSI GRB team, and K.Yamaoka, M.Ohno, Y.Fukazawa, T.Takahashi, M.Tashiro, Y. Terada, T.Murakami, and K.Makishima on behalf of the Suzaku WAM team report: A short, hard GRB was observed at 2006-04-25 16:57:40 by Swift-BAT, Konus-Wind, Suzaku-WAM, RHESSI, and INTEGRAL-SPI-ACS. The T90 was 0.13 +- 0.01 sec. This burst was Mars-occulted to Odyssey. The burst had 2 main peaks of roughly similar intensity and hardness, the second slightly shorter than the first. The IPN triangulated error box is as follows: ---------------------- RA, deg Dec, deg (J2000) ---------------------- Center: 212.3007 -5.0667 Corners: 214.5693 -1.7277 210.9652 -7.0326 210.7765 -8.4092 213.8848 -3.1685 ----------------------- The area of the box is 2.53 sq. deg Preliminary analysis of the Konus-Wind data yields a burst fluence of 2.57 (-1.85, +0.47) x 10^-6 erg/cm2. The peak flux measured from T0(K-W)-0.036 s on a 16-ms time scale was 3.64 (-2.74, +1.06) x 10^-5 erg/cm2/sec. Both are quoted in the 20 keV - 10 MeV energy range. The K-W spectrum accumulated from T0(K-W) to T0(K-W)+0.128 s is well fitted (in the 20 keV - 10 MeV range) by a power law with exponential cutoff model: dN/dE ~ E^(-alpha) * exp(-(2-alpha)*E/Ep) with alpha = 0.92 (-0.37, + 0.28) and Ep = 1403 (-594, 1273) keV (chi^2 = 16.7/18 dof). T0(K-W) = 61063.000 s UT (16:57:43.000). We note that the X-ray source 1RXS J140902.5-050430, and nearby galaxies LEDA 1048719 and LEDA 1047950 are within this error box close to the center.