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GCN Circular 2335

GRB 030725: optical observations.
2003-07-29T18:40:59Z (20 years ago)
Javier Gorosabel at LAEFF-INTA, Madrid <>
C. Vinter, S. Jorgensen (U. Copenhagen), J. Gorosabel (IAA-CSIC/STScI), 
J. Hjorth, B. L. Jensen (U. Copenhagen), J. P. U. Fynbo (U. Aarhus) report:

"We observed the optical transient (Monard, GCN ##2324,2334) located inside 
the HETE-2 error box of GRB 030725 (Shirasaki et al., GCN #2322) with the 
Danish 1.5-m telescope on July 29.38 2003. The optical transient is detected 
at R = 21.2 +- 0.2 (preliminary calibration, partly based on zero points
from previous nights, partly on USNO-B1.0 reference stars). The resulting
decay rate is quite slow, with an average power-law decay index of ~ -0.9
since the detection 7 hours after the burst (Monard GCN #2324)."
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