[vsnet-grb-info 16900] GRB150819A: NOT imaging

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18181
SUBJECT: GRB150819A: NOT imaging
DATE:    15/08/20 15:28:20 GMT
FROM:    Steve Schulze at U of Iceland  <sts30 at hi.is>

S. Schulze (PUC, MAS), D. Malesani, J. P. U. Fynbo (DARK, NBI), J. Duus, T. Hinz-Berg, O. Busborg Jensen (NBI) and P. Jakobsson (U Iceland) report on behalf a larger collaboration:

We observed the field of GRB 150819A (Ukwatta et al., GCN 18163) with the Nordic Optical Telescope (NOT) equipped with ALFOSC. We obtained 4 images in the I band and 3 images in the z band with an individual sub-exposure time of 300 s. Observations started at 02:01 UT on August 19 (i.e. 1.19 hr after the burst).

We detect no credible source in the co-added I and z band images at the refined XRT localisation (Evans et al., GCN 18167). The limiting magnitude of the I-band image is 23 mag (3 sigma, Vega). This value is not corrected for foreground extinction. The flux calibration of the z-band image is still pending.