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GCN Circular 9870

GRB 090902B: Optical afterglow candidate
2009-09-03T05:30:08Z (15 years ago)
Daniel Perley at U.C. Berkeley <>
D. A. Perley, I. K. W. Kleiser, and J. M. Rex (UC Berkeley) report:

We imaged the location of the Swift-XRT candidate afterglow (GCN 9868, 
Kennea et al.) of extremely bright Fermi GRB 090902B (GCN 9866, Bissaldi 
et al.) with the Nickel 1-meter telescope at Lick Observatory.  We 
marginally detect a faint source in individual 600-second exposures at 
the western edge of the XRT error circle with a magnitude comparable to 
the Digitized Sky Survey limit.  This is likely the same source observed 
by the UVOT (GCN 9868, Swenson et al.).

We cannot confirm fading behavior at this time, and further observations 
are encouraged.  A finding chart showing the XRT error circle and the 
putative afterglow is available at the following URL:
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