{
  "bibcode": "2003GCN..2322....1S",
  "body": "GRB030725 (=H2779): A Bright GRB Localized by the HETE WXM and SXC\n\nY. Shirasaki, T. Tamagawa, M. Suzuki, C. Graziani, T. Donaghy, M.\nMatsuoka, K. Torii, T. Sakamoto, A. Yoshida, E. Fenimore, M. Galassi,\nY. Nakagawa, R. Satoh, Y. Urata, T. Yamazaki and Y. Yamamoto, on\nbehalf of the HETE WXM Team;\n\nG. Ricker, J-L. Atteia, N. Kawai, D. Lamb, and S. Woosley\non behalf of the HETE Science Team;\n\nG. Prigozhin, N. Butler, G. Crew, J. Doty, A. Dullighan, R.\nVanderspek, J. Villasenor, T. Cline, J. G. Jernigan, A. Levine, F.\nMartel, E. Morgan, G. Monnelly, G. Azzibrouck, J. Braga, R.\nManchanda, and G. Pizzichini, on behalf of the HETE Operations and\nHETE Optical-SXC Teams;\n\nC. Barraud, M. Boer, J-F Olive, J-P Dezalay, and K. Hurley on behalf \nof the HETE\nFREGATE Team;\n\nwrite:\n\nAt 11:46:24.82 UTC (42384.82 s UT) on 25 July 2003, the HETE FREGATE \nand WXM instruments detected  GRB030725 (=H2779), a bright, \ndouble-peaked long GRB located at high galactic latitude (b = 37 \ndegrees).\n\nThe burst triggered Fregate in the 5-120 keV energy band. A GCN burst \nalert was issued 2.6 m later. Because the source was located at the \nextreme edge of the FOV of the WXM Y counter, no flight localization \nwas derived. Ground analysis of the WXM data provided a localization \nthat was reported in a GCN Notice at 13:19:34 UT. The WXM \nlocalization can be expressed as a 90% confidence error region that \nis centered at:\n\nWXM Center-ground:   RA= 20h 33m 34s,  Dec= -50d 45' 30\"  (J2000)\n\nThe WXM error region is unusually elongated because of the very low \nexposure of the Y detector. The four corners of the WXM error region \nare located at J2000 coordinates:\n\nWXM_CORNER1:    \tRA= 20h 33m 53.3s, Dec= -51d 00' 04\"\nWXM_CORNER2:    \tRA= 20h 33m 15.3s, Dec= -50d 59' 02\"\nWXM_CORNER3:    \tRA= 20h 33m 15.1s, Dec= -50d 30' 58\"\nWXM_CORNER4:    \tRA=\t20h 33m 52.8s, Dec= -50d 31' 59\"\n\nGround analysis of the SXC data provided a better localization that \nwas disseminated as a GCN notice at 16:07:46 UT. The SXC localization \ncan be expressed as a 90% confidence error region that is centered at:\n\nSXC Center-Ground:   RA= 20h 33m 47s , Dec= -50d 45' 49\"  (J2000)\n\nThe SXC X camera detected the burst, but the SXC Y camera did not. We \nwere able to use the WXM Y localization to constrain the SXC error \nregion in the Y direction. The four corners of the SXC error region \nare located at J2000 coordinates:\n\nSXC_CORNER1:    RA= 20h 33m 36.5s, Dec= -50d 59' 35\"\nSXC_CORNER2:    RA= 20h 33m 57.3s, Dec= -51d 00' 11\"\nSXC_CORNER3:    RA= 20h 33m 56.6s, Dec= -50d 32' 06\"\nSXC_CORNER4:    RA= 20h 33m 35.7s, Dec= -50d 31' 30\"\n\nH2779 was comprised by two FRED-like* peaks, separated by ~160s. The \nduration of the first peak was ~40s, while that of the second peak \nwas ~10s. A total of 25000 counts were detected in the 7-30 keV \nenergy band during the ~180s interval encompassing both peaks, \ncorresponding to a fluence of ~5 x 10-6 ergs cm-2. The peak flux \nwas >2 x 10-7 ergs cm-2 s-1 (ie >5 x Crab flux) in the same energy \nband. [* FRED = Fast rise, exponential decay]\n\nIn the 30-400 keV band, the fluence was ~2 x 10-5 ergs cm-2, which is \n~4 times the fluence in the 7-30 keV band. Thus, H2779 appears to be \na \"classical\" long hard burst.\n\nA light curve and finding chart for GRB030725 is provided at the following URL:\n\nhttp://space.mit.edu/HETE/Bursts/GRB030725\n\nThis message may be cited.",
  "circularId": 2322,
  "createdOn": 1059175104000,
  "email": "grr@space.mit.edu",
  "subject": "GRB030725 (=H2779): A Bright GRB Localized by HETE",
  "submitter": "George Ricker at MIT  <grr@space.mit.edu>",
  "eventId": "GRB 030725"
}