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GCN Circular 9884

GRB 090904A: NOT observations
2009-09-04T10:50:17Z (15 years ago)
Pall Jakobsson at U of Iceland <>
D. Malesani (DARK/NBI), P. Jakobsson (U. Iceland), N. Tanvir
(U. Leicester) and I. Ilyin (AIP) report on behalf of a larger

We observed the field of GRB 090904A (Perri et al., GCN 9879)
with the Nordic Optical Telescope equipped with StanCam.
Observations were carried out on 2009 Sept 4.17 (3.1 hr after
the GRB) in the R- and I-bands. No objects are detected inside
the XRT error circle to a limit of R > 23. However, just outside
the error circle at

RA(J2000)  =  06:43:32.33
Dec(J2000) = +50:12:12.4

there is an object with R = 22 +/- 0.2 mag (calibrated against
several nearby USNO-B1 stars). If weather permits, further
observations are planned tonight to estimate whether the object
is fading.
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