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GCN Circular 2707

Optical observations of GRB/XRF 040912 = HETE 3557
2004-09-13T14:35:54Z (20 years ago)
Jens Hjorth at U.Copenhagen <>
M. I. Andersen (AIP), M. Weidinger (U. Aarhus), J. Hjorth, J. P. U. Fynbo,
B. L. Jensen (U. Copenhagen) report:

"Using the ALFOSC at the 2.56-m Nordic Optical Telescope, La Palma, we have
obtained 2 x 2 mosaic CCD images covering the HETE-2 error circle of
GRB/XRF 040912 (Butler et al., GCNC 2701) on two epochs. Each pointing
consists of 3 x 300 sec in the R band.

Comparison of the two epochs (Sep 12.92-12.97 and Sep 13.19-13.24 2004 UT)
through visual inspection and difference imaging does not reveal any sources
exhibiting significant variability between the two epochs. The 3-sigma
variability limit is R ~ 23.4."
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