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GCN Circular 365

GRB990704, optical observations
1999-07-05T13:25:04Z (25 years ago)
Fredrick J. Vrba at USNO <>
The U.S. Naval Observatory GRB team (F.J. Vrba, A.A. Henden, C. B.
Luginbuhl, B. Canzian, S.E. Levine), D.H. Hartmann (Clemson Univ.) and, 
M.C. Jennings (IGPP, UCR visitor) reports:

We have obtained calibrated photometric observations, under clear sky
conditions, of the 7-arcmin radius error circle for GRB 990704,
reported by Gandolfi et al. in GCN 361. R-band (Cousins) observations 
were obtained at the U.S. Naval Observatory, Flagstaff Station
1.0-m reflector using a CCD with an 11x11 arcmin field.  Four 12 minute
observations were mosaiced to cover a 15x15 arcmin field centered on
the GCN 361 coordinates.  The observations were obtained between
UT 1999 July 05 04:02 and 04:57.  The frames reached a 3-sigma limiting 
detection of Rc = 21.2.  No obvious new objects were detected in a 
comparison with the Digital Sky Survey.

[GCN OPS NOTE:  This message was received at 09:45 UT 05 Jul 99.]
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