TITLE: GCN GRB OBSERVATION REPORT NUMBER: 5030 SUBJECT: GRB 060427B: IPN localization of a short hard burst DATE: 06/04/28 18:55:15 GMT FROM: Kevin Hurley at UCBerkeley/SSL S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin, and D. Frederiks on behalf of the Konus-Wind team, K. Hurley and T. Cline on behalf of the Ulysses, Mars Odyssey, and Konus GRB teams, I. Mitrofanov, A. Kozyrev, M. Litvak, A. Sanin, V. Tret'yakov and A. Parshukov, 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, S. Barthelmy, J. Cummings, N. Gehrels, and H. Krimm, on behalf of the Swift-BAT team, and A. von Kienlin, G. Lichti, A. Rau, D. Gotz, and S. Mereghetti, on behalf of the INTEGRAL GRB team, report: A short duration hard spectrum GRB, 060427B, occurred at about 23:51:55 UT. It was observed by Konus-Wind, Mars Odyssey (GRS and HEND), INTEGRAL-SPI-ACS, and Swift-BAT. The burst was outside of the field of view of Swift-BAT, so it was not imaged. As the burst arrived almost along the Odyssey-Earth vector, the resulting annulus was unusually wide. The burst light curve shows a single pulse with a duration of ~0.2 sec. A weak emission is seen in the K-W G2 band (83-360 keV) starting at ~0.3 sec before the main pulse. The burst has been triangulated to RA, Dec = 98.472, +21.348 deg (J2000). The corners of the 3 sigma error box are: ----------------------- RA, deg Dec, deg ----------------------- 98.8479 22.7146 98.7014 19.9202 98.0629 19.9948 98.1954 22.8568 -------------------- The area of this error box is 1.7 sq. deg. Konus-Wind spectral analysis is in progress. Preliminary analysis indicates that Epeak was >1 MeV.