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GCN Circular 9141

GRB 090417B: optical observations
2009-04-18T01:25:33Z (15 years ago)
Igor Volkov at Asro.Inst.Slovak Acad.Sciences <>
On 2009 April 17  I observed the field of GRB 090417B (Sbarufatti et al.
GCN Circ. 9135) with the 0.5m reflector and ST-10XME CCD camera of Stara
Lesna (Slovak Republic) observatory. I have got 11 frames in standard Rc
system, starting at 22:10:05 UT, 23332s after the alert. In my coadded
frame (total exposition 930s)it was not possible to detect a single source
inside the refined XRT error box (Sbarufatti et al. GCN Circ. 9135) with
S/N rate more than 5, which corresponds to limiting magnitude Rc >19.9.
The time of the middle of the sequence was 22:18:00 UT. GSC2.3 catalog was
used for flux calibration.

Igor Volkov, visiting astronomer of Astronomical Institute of the Slovak
Academy of Sciences, 059 60 Tatranska Lomnica, Slovak Republic; Sternberg
Astronomical Institute, 119992  Moscow, Universitetskij pr.13;
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