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GCN Circular 82

GRB980519 Optical Observations
1998-05-20T19:55:36Z (26 years ago)
Eric Deutsch at U.Washington <>
On behalf of the Apache Point Observatory GRB team, A. Diercks & C.
Stubbs observed with the APO 3.5m telescope the optical transient (OT)
discovered by Jaunsen et al. (GCN #78) in the BeppoSAX error box of GRB
980519.  Conditions were mostly cloudy with roughly 1.8 arcsec seeing.
Photometry by E. Deutsch & A. Diercks on a 1 hr series of images
centered around May 20.44 UT yields the following magnitudes and
relative uncertainties for the OT and reference stars:

ID  R mag  RelErr
--  -----   -----
OT  21.20    0.03
A   17.93    0.01
B   19.31    0.01
C   18.06    0.01

Absolute calibration is based only on R magnitudes of reference stars
reported by Kemp & Halpern (GCN #80).  No independent calibration was
possible due to heavy clouds.  Our measurement is 0.3 mag fainter than
the earlier observations of Kemp & Halpern (GCN #80).

Images are posted at:

This note can be cited.
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