{
  "bibcode": "2003GCN..2313....1P",
  "submitter": "George Ricker at MIT  <grr@space.mit.edu>",
  "createdOn": 1059003596000,
  "subject": "XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and",
  "version": 2,
  "circularId": 2313,
  "email": "grr@space.mit.edu",
  "editedBy": "Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov>",
  "body": "XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and SXC\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\nG. Ricker, J-L. Atteia, N. Kawai, D. Lamb, and S. Woosley\non behalf of the HETE Science Team;\n\nC. Barraud, M. Boer, J-F Olive, J-P Dezalay, and K. Hurley on behalf \nof the HETE\nFREGATE Team;\n\nT. Tamagawa, M. Suzuki, C. Graziani, Y. Shirasaki, 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\nwrite:\n\nAt 06:28:17.45 UTC (23297.45 s UT) on 23 July 2003, the HETE FREGATE, \nWXM, and SXC instruments detected an X-ray flash, designated \nXRF030723 (=H2777), located at high galactic latitude (b = 50 \ndegrees).\n\nThe burst triggered the WXM in the 2-25 keV energy band. The burst \nsignal-to-noise was ~9.  A GCN burst alert was issued 42s later, \nreporting a flight-derived WXM localization with a 30 arcmin radius \n(90% confidence). Ground analysis of the WXM data produced a \nlocalization that was reported in a GCN Notice at 09:47:25 UT. The \nWXM data provided a localization that can be expressed as a 90% \nconfidence circle that is 9.4 arcminutes in radius and is centered \nat--\n\nWXM-ground:   RA= +21h 48m 52s,  Dec= -27d 41' 16\"  (J2000)\n\nGround analysis of the SXC data provided an initial localization that \nwas disseminated as a GCN Notice at 13:38:19 UT. A refined SXC \nlocalization can be expressed as a 90% confidence circle that is 2 \narcmin in radius and is centered at--\n\nSXC-Ground:   RA= +21h 49m 27.4s, Dec= -27d 42' 01\"  (J2000)\n\n\nThe burst duration (t90) in the 7-30 keV band was ~23 s. A total of \n1210 counts were detected by Fregate during that interval, \ncorresponding to a fluence of ~2 x 10-7 ergs cm-2. The peak flux in a \n1.2 s bin was >3 x 10-8 ergs cm-2 s-1 (ie >0.9 x Crab flux) in the \nsame energy band.\n\nIn the 30-400 keV band, the fluence was < 0.7 x 10-7 ergs cm-2, which \nis  < 0.4 times the fluence in the 7-30 keV band; thus we conclude \nthat H2777 is an X-ray flash.\n\nA light curve and finding chart for XRF030723 is provided at the following URL:\n\nhttp://space.mit.edu/HETE/Bursts/GRB030723\n\nThis message may be cited.",
  "editedOn": 1777052898100,
  "eventId": "XRF 030723"
}