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GCN Circular 349

GRB990527 Optical Observations
1999-05-31T16:21:11Z (25 years ago)
Holger Pedersen at Copenhagen U Obs <>
H. Pedersen, J. Hjorth, B. L. Jensen (Copenhagen), M. B. Rasmussen (Aarhus), 
A. O. Jaunsen (Oslo), and K. Hurley (UCBerkeley/SSL) report: 

"We have observed the field toward the Ulysses + KONUS-WIND + NEAR IPN 
localization of GRB 990527 (GCN #347) with the DFOSC at the Danish 1.54-m 
telescope on La Silla. The FOV was 13.4' x 13.4' and thus covers most of 
the IPN diamond. Five 8 min exposures and one 10 min exposure were obtained 
in the R band between 29.33 May and 29.44 May 1999 UT. The seeing FWHM was 
2.0". Seven additional 10 min R band exposures were obtained between 
30.33 May and 30.45 May 1999 UT, in 1.1" seeing. All images were taken in 
strong moon-light. The combined exposure covers 12.5' x 12.5'. 

Visual inspection of the images revealed no object inside the IPN diamond 
that was not present on the DSS-2 ('Second Epoch Southern' survey, UK Schmidt, 
IIIaF + RG610 red plate) and brighter than the DSS-2 magnitude limit. 
Comparison between the images obtained on 29.4 May and 30.4 May revealed no 
significantly variable object above a magnitude limit of R = 22.0.

For finding charts, see . 
This page also gives details on two stars, which stand out in comparison to
the DSS; both are off the error box, and non-variable during the CCD 
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