{
  "bibcode": "2001GCN..1103....1R",
  "body": "GRB010928(=H1770): Localization of a Long GRB by HETE\n\nG. Ricker, D. Lamb, and S. Woosley on behalf of the HETE Science Team;\n\nG. Crew, R. Vanderspek, J. Doty, G. Monnelly, J. Villasenor, N. Butler,\nT. Cline, J.G. Jernigan, A. Levine, F. Martel, E. Morgan, G.\nPrigozhin, J. Braga, R. Manchanda, and G. Pizzichini, on behalf of\nthe HETE Operations and HETE Optical-SXC Teams;\n\nN. Kawai, M. Matsuoka, Y. Shirasaki, T. Tamagawa, K. Torii, T. Sakamoto,\nA. Yoshida, E. Fenimore, M. Galassi, T. Tavenner, T. Donaghy, and\nC. Graziani, on behalf of the HETE WXM Team;\n\nJ-L Atteia, M. Boer, J-F Olive, J-P Dezalay, and K. Hurley on behalf\nof the HETE FREGATE Team;\n\nwrite:\n\nAt 16:53:46.56 UTC (60826.56 s UT) on 28 September, the HETE FREGATE \nand WXM instruments detected and localized a long GRB. The burst, \nH1770, was promptly reported as a GCN Alert Notice within 13 seconds \nof the detection time. The burst is seen in the WXM X detector and is \ntherefore well-localized in the X direction; the burst was apparently \nnear the edge of the coded FOV of the WXM Y detector, resulting in a \nlarge uncertainty in the Y direction localization.\n\nThe X-detector data gives a good (+/- 6 arcmin) localization in the X \ndirection and crude limits on Y, resulting in a localization that is \na long, thin strip.\n\nThe coordinates (J2000) of two points along one side of the strip are:\n\nR.A. = 23h29m44s.1, Dec. = 29o39'36\"; R.A. = 23h27m05s.7, Dec. = 31o34'34\"\n\nThe coordinates (J2000) of two points along the other side of the strip are:\n\nR.A. = 23h30m42s.9, Dec. = 29o43'41\"; R.A. = 23h28m04s.5, Dec. = 31o38'42\"\n\nThe length of the strip is uncertain. Our best estimate is that it is \nless than 10 degrees in length, and is centered on  R.A. = \n23h28m55s.1, Dec. = 30o39'11\".\n\nThe burst duration  was ~40 s, with two peaks separated by ~20 s. In \nthe 8-85 keV band, a total of 6,330 counts were detected  during the \nburst, corresponding to a fluence of ~1 x 10-6 ergs cm-2; the peak \nflux was >7 x 10-8 ergs cm-2 s-1 (ie >2 x Crab flux). In the 32-400 \nkeV band, a total of 9,530 counts were detected during that interval, \ncorresponding to a fluence of ~3 x 10-6 ergs cm-2; the peak flux \nwas >2 x 10-7 ergs cm-2 s-1 (ie >14 x Crab flux).\n\nFurther refinement of the X localization is in progress; a further\nattempt is also being made to improve the coarse Y localization.\n\nFollow-up observations of this transient are encouraged.",
  "circularId": 1103,
  "createdOn": 1001718230000,
  "email": "grr@space.mit.edu",
  "subject": "GRB010928(=H1770): Localization of a Long GRB by HETE",
  "submitter": "George Ricker at MIT  <grr@space.mit.edu>",
  "eventId": "GRB 010928"
}