{
  "bibcode": "1999GCN...255....1F",
  "body": "Andrew Fruchter, Kailash Sahu, Harry Ferugson, Mario Livio \n      and Mark Metzger on behalf of the larger HST GRB \n      collaboration report:\n\nWe have reduced the HST STIS CCD clear (50CCD) images of\nGRB 990123 announced earlier today by the Director of STScI,\nSteven Beckwith, in GCN 254.\n\nWe find the optical transient to be superposed on an extended\nirregular galaxy.   A quick photometric reduction shows that\nthe OT has a magnitude of V=25.4 +/- 0.1 and the galaxy has \nV=24.3 +/- 0.15.  The total integrated magnitude of the galaxy \nand OT is therefore V~24, which agrees with Palomar 5-m observations \ntaken approximately 12 hours before the HST observations, and\nwhich will be reported in a succeeding GCN.  No correction\nto the STIS magnitude has yet been made to take into account\nthe colors of the objects, which could change the estimated \nmagnitudes from the broad STIS clear filter by ~0.1 mag.\n\nThe faint magnitude of the OT suggests that it may be declining\nmore rapidly than the earlier power-law would predict, as \nsuggested by the MDM group in GCN 248.\n\nThe probable host galaxy is itself composed of several irregular \npieces, extended over a region more than 1\" across.  The major \nfraction of the light in the host is to the north of the OT, thus \nagreeing with the probable extension reported by Djorgovski et\nal. in GCN 243.\n\nA gif image as well as the reduced FITS files will be posted\nby 16:00 EST today (9 February 1999) on \n\nhttp://www.stsci.edu/~fruchter/GRB/990123\n\nWe welcome the use of the reduced FITS image by others; \nhowever, we ask that those who do use this image cite \nthis GCN, or a formal publication that may succeed it\n(the bibliographic reference of which would be available \non the above web page).",
  "circularId": 255,
  "createdOn": 918588171000,
  "email": "fruchter@stsci.edu",
  "subject": "GRB 990123: Reduced HST Images",
  "submitter": "Andrew S. Fruchter at STScI  <fruchter@stsci.edu>",
  "eventId": "GRB 990123"
}