{
  "bibcode": "2000GCN...627....1F",
  "body": "A. Fruchter (STScI), A. Smette (GSFC), T. Gull (GSFC), H. Ferguson, L. Petro, \nJ. Rhoads, and K. Sahu (STScI) for a larger HST GRB Collaboration:\n\nWe have re-imaged the field of GRB 000301C with HST using the STIS CCD \nin both 50CCD (open) and LP (long-pass) mode. The observations were \ncentered about 3.9 April 2000 UT with total exposure times of 2280s \nin both filters.  \n\nWe detect a bright source on a fainter extended object at the position\nof the optical transient (OT).  The position of the peak of emission\nfrom the object agrees with that of the OT on previous HST images taken\non 6 March 2000 (see GCN 602) to better than 0.\"01, based on astrometry\nrelative to other objects visible in both HST images.  We believe\ntherefore we are observing continued emission from the OT of GRB 000301c,\nas well as from its host galaxy.   One cannot give a precise magnitude\nfor the OT without knowing a priori the surface brightness profile of\nthe host.  However, what we consider the best point source subtraction\nimplies an OT magnitude of R=26.9; in any case, the point source is\nno brighter than R=26.7.   The total magnitude of the OT plus\nhost is 26.5 +/- 0.15 on 3.9 April 2000.    Although no upper limit\nto the magnitude of the OT can truly be given without knowledge\nof the host, we note that R=26.9 is within 0.1 mag of the value\npredicted for this date by the fit to earlier R band data given\nin Rhoads and Fruchter (astro-ph/0004057).  This provides some further\nconfidence that our best estimate of the OT strength is not far off.\nIf this value is used for the magnitude of the OT, then the host galaxy \nhas a magnitude R = 27.8 +/- 0.25.   \n\nThe  STIS filter set only gives limited color information, however,\nour observations agree well with the spectral index of -0.9\nreported by Halperin  (GCN 585).   A change to a spectral index\nof -3, as has been seen in the late time spectra of some other\nGRBs, would most likely have been detected.\n\nThe HST images of GRB 000301c are available at:\nhttp://www.stsci.edu/~fruchter/GRB/000301C",
  "circularId": 627,
  "createdOn": 955330738000,
  "email": "fruchter@stsci.edu",
  "subject": "GRB 000301C: Late-Time HST/STIS CCD Imaging of the field",
  "submitter": "Andrew S. Fruchter at STScI  <fruchter@stsci.edu>",
  "eventId": "GRB 000301C"
}