GCN Circular 80

The MDM Observatory GRB team (J. Kemp, J. Halpern) reports followup
photometry of the variable optical candidate discovered by Jaunsen et al.
(GCN #78) in the BeppoSAX error box of GRB 980519.  In a series of CCD
images taken with the MDM 1.3m telescope, centered around May 20.31 UT,
the candidate had I=20.1+/-0.3, R=20.9+/-0.2.  These magnitudes were
measured differentially with respect to stars A, B, and C of Jaunsen et
al., which we recalibrated using Landolt standards.  Preliminary
photometry of those reference stars is as follows:

	      RA(2000)       Dec(2000)         R        I

	A    23 22 17.74    +77 15 51.2      17.93    17.28
	B    23 22 27.29    +77 15 43.5     (19.26)  (18.56)
	C    23 22 28.50    +77 15 25.4      18.15    17.43

Parentheses indicate values that are less certain.  Note the large
discrepancy between our I-band measurements and those of Jaunsen et al.; 
the latter may instead refer to the V band.

MDM images will be posted at http://cba.phys.columbia.edu/jonathan/grb/.

This note can be cited.