{
  "bibcode": "2002GCN..1716....1S",
  "body": "M. Sako & F. A. Harrison report on behalf of the Caltech-NRAO \ncollaboration:\n\nWe report a second TOO observation of GRB021004 taken with the Advanced CCD\nImaging Spectrometer (ACIS-S) onboard the Chandra X-ray Observatory.  The\nobservation started at 17:35 on November 25 (52.229 days after the GRB) for a\ntotal exposure time of 30.0 ksec.  Ten counts were detected in a circular\nregion with a radius of 1 arcsec centered on the source position of GRB021004,\nof which 1 - 2 photons are estimated to be background events.  Assuming the\nsame power-law spectral index as that observed during an earlier Chandra observation\n(GCN 1624), this corresponds to a 2 - 10 keV flux of (7.2 +/- 2.5) x 10^-16\nerg/cm2/s.  The source, therefore, has decayed with a characteristic power\nlaw decay time slope of approximately -1.7 since the previous observation.\n\nThe data can be accessed through the Chandra Data Archive.  We thank Harvey\nTananbaum for allocating Director's Discretionary Time and the Chandra X-ray\nCenter for implementing the obervation.",
  "circularId": 1716,
  "createdOn": 1038723553000,
  "email": "fiona@srl.caltech.edu",
  "subject": "GRB021004 Chandra Observation",
  "submitter": "Fiona Harrison at CalTech  <fiona@srl.caltech.edu>",
  "eventId": "GRB 021004"
}