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GCN Circular 18164

GRB150818A: NOT imaging
2015-08-19T01:04:40Z (9 years ago)
Steve Schulze at U of Iceland <>
S. Schulze (PUC, MAS), J. P. U. Fynbo (DARK, NBI), T. Kruehler (MPE), D. Malesani, (DARK/NBI), I. V. Rasmussen, J. L. Marcher, L. L. Thomson (NBI), A. Djupvik (NOT), B. Milvang-Jensen (DARK/NBI) and P. Jakobsson (U Iceland) report on behalf a larger collaboration:

We observed the field of GRB 150818A (D'Elia et al., GCN 18152) with the Nordic Optical Telescope (NOT) equipped with ALFOSC. We obtained a 180 s and a 3x300 s image in R band. Observations started at 21:34 UT on August 18 (i.e. 9.62 hr after the burst).

We clearly detect the source reported in Marshall et al. (GCN 18155) and McCauley et al. (GCN 18161). We measure R=20.86 +/- 0.08 mag calibrated against several USNO stars. This value is not corrected for foreground extinction. 

Given the lack of evidence for variability (McCauley et al., GCN 18161), the association of this object with GRB 150818A remains unclear.
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