TITLE:   GCN CIRCULAR
NUMBER:  12054
SUBJECT: GRB 110530A: NOT optical observations
DATE:    11/05/31 03:04:40 GMT
FROM:    Annalisa De Cia at U of Iceland  <annalisa@raunvis.hi.is>

A. De Cia, P. Vreeswijk (U. of Iceland), D. Xu (Weizmann Inst.),
J. Telting (NOT) and P. Jakobsson (U. of Iceland)

report on behalf of a larger collaboration:

We observed the field of D'Avanzo et al. (GCN 12046) with the
2.5m NOT telescope at Roque de los Muchachos Observatory (La
Palma, Spain) equipped with ALFOSC, starting at 22:18 UT (6.8h
after the burst). The optical afterglow is detected, within the
XRT error circle reported by D'Avanzo et al., at R ~ 21.3,
calibrated against the USNO-B1.0 1519-0265568 star (R2=16.08)
also adopted by Andreev et al. GCN 12052.

Preliminary reduction of the subsequent spectroscopic
observations does not show any evident absorption lines, given
the poor S/N. A rough limit on the source redshift z<2.7 may be
placed by the non-detection of Lyman alpha absorption in the
spectra.