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GCN Circular 467

GRB 991208 optical observations
1999-12-17T06:11:35Z (25 years ago)
Alberto Castro-Tirado at Astro. de Andalucia <>
GRB 9901208

Vijay Mohan, Anil K. Pandey, Ram Sagar and S.B. Pandey (from UPSO,
Nainital) and Alberto J. Castro-Tirado (INTA, Madrid and IAA, Granada)
-on behalf of a larger European collaboration- report:

"We have imaged the field of GRB 991208 with the 2k x 2k CCD camera
on the UPSO 104-cm telescope on 1999 Dec 12.0 (UT); Dec 13.0 (UT) and
Dec 14.0
(UT) in I photometric passband during photometric sky conditions. The
transient of the GRB 991208 (Castro-Tirado et al. GCN  452) is fading
about 0.5 mag between Dec 12 and 13. This indicates a power decay index
-2.0. The object has become so faint for our telescope that it is barely

visible on the 1 hour CCD image. Thus flux decay in I is almost similar
that in R filter (Jensen et al. GCN 454; Garnavich et al. GCN  456).
Calibration of the field is in progress.

This message is citable."
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