{
  "bibcode": "2004GCN..2536....1N",
  "body": "Y. Nakagawa, G. Ricker, J-L. Atteia, N. Kawai, D. Lamb, and S. Woosley,\non behalf of the HETE Science Team;\n\nT. Donaghy, E. Fenimore, M. Galassi, C. Graziani, M. Matsuoka,\nT. Sakamoto, R. Satoh, Y. Shirasaki, M. Suzuki, T. Tamagawa, K. Torii,\nY. Urata, T. Yamazaki, Y. Yamamoto, and A. Yoshida, on behalf of the\nHETE WXM Team;\n\nN. Butler, G. Crew, J. Doty, A. Dullighan, G. Prigozhin, R. Vanderspek,\nJ. Villasenor, J. G. Jernigan, A. Levine, G. Azzibrouck, J. Braga,\nR. Manchanda, and G. Pizzichini, on behalf of the HETE Operations and\nHETE Optical-SXC Teams;\n\nM. Boer, J-F Olive, J-P Dezalay, C. Barraud, and K. Hurley, on behalf\nof the HETE FREGATE Team;\n\nreport:\n\nAt 00:08:55.95s UTC (535.95s UT) and 00:12:44.08s UTC (764.08s UT) on\n2004 February 28, the HETE-2 FREGATE instrument detected triggers H3066\nand H3067.  H3066 is a multi-peaked burst with a duration of ~40s in\nthe FREGATE 7-80 and 30-400 keV energy bands; no significant emission\nassociated with H3066 is seen in the WXM 2-25 keV energy band or in the\nFREGATE 7-40 keV energy band.  H3067 consists of a single peak with a\nduration of ~10 seconds in the FREGATE 30-400 keV energy band; again,\nno significant emission associated with H3067 is seen in the WXM 2-25\nkeV energy band or in the FREGATE 7-40 keV energy band.\n\nAt ~00:13:24 UTC (~800 UT) (~40 seconds after trigger H3067), an X-ray\npulse with a duration of >50 seconds is visible in the WXM 2-15 keV\nenergy band.  Ground analysis of the WXM data produced a localization\nthat was reported in a GCN Notice at 02:22:44 UT.  The WXM localization\ncan be expresssed as a 90% confidence rectangle whose center is at\n\nWXM-ground: RA = +10h 12m 12s, Dec = -07d 19' 33\" (J2000),\n\nand whose corners lie at\n\nWXM-ground: RA =  +10h 12m 55.6s, Dec = -7d 48' 36\"\n            RA =  +10h 11m 29.3s, Dec = -7d 47' 46\"\n            RA =  +10h 11m 28.8s, Dec = -6d 50' 35\"\n            RA =  +10h 12m 55.4s, Dec = -6d 51' 22\" (J2000).\n\nThe spectrum of the X-ray pulse is such that, had it been detected\nalone, it would be classified as an XRF.  However, the temporal\ncoincidence with the two preceding triggers suggests that the X-ray\npulse may be associated with them, and is in fact a soft late phase of\nthe GRB.  Because we are unable to localize either H3066 or H3067, we\nare unable to confirm this possibility at this time.  An IPN\nlocalization of either H3066 or H3067 could help to resolve the\nsituation, and to determine whether H3066, H3067, and the X-ray pulse\nare all part of the same burst or not.\n\nLight curves for H3066, H3067, and the X-ray pulse, and a skymap\nshowing the localization of the X-ray pulse is provided at the\nfollowing URL:\n\nhttp://space.mit.edu/HETE/Bursts/GRB040228.",
  "circularId": 2536,
  "createdOn": 1077946189000,
  "email": "lamb@oddjob.uchicago.edu",
  "subject": "GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM",
  "submitter": "Don Lamb at U.Chicago  <lamb@oddjob.uchicago.edu>",
  "eventId": "GRB 040228"
}