GCN Circular 1822

F. Vrba (USNO), C. Luginbuhl (USNO), A. Henden (USRA/USNO)
report on behalf of the USNO GRB team:

We have imaged the field of GRB030115 (Kawai et al., GCN 1816
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 )
at B and V with the NOFS 1.0m telescope on 030115 UT, at J and
H with the NOFS 1.55m telescope on 030115 UT, and at H on
030116 UT (poor seeing).  The B and V data only goes roughly as
deep as DSS-2 due to cirrus and moonlight; the J and H datasets go
significantly deeper than either DSS-2 or 2MASS.
   At the position of the afterglow candidate suggested by Levan et al.
(GCN 1818
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 ) we confirm a fading object, visible on the 030115 UT H-band
image but not on the 030116 UT H-band image.  We measure the position
of the counterpart on the 030115 UT image as:

   11:18:32.61  +15:02:59.9  J2000

using the USNO-A2.0 reference catalog; estimated coordinate
errors are +/- 200mas.  These coordinates can be improved.
   Depending on weather, we expect to be able to calibrate this
field at JHK within the next few nights.  We also expect to
do a shallow BVRI calibration, extending it fainter when
closer to new moon.