[vsnet-grb-info 6477] GRB 080810: Observations from NOT

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  8089
SUBJECT: GRB 080810: Observations from NOT
DATE:    08/08/11 07:15:29 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte at iaa.es>

A. de Ugarte Postigo (ESO), C.C. Thoene, J.P.U. Fynbo,
J. Hjorth (DARK/NBI), P. Jakobsson (U. Hertfordshire),
Z. Banhidi (NOT, IAC), F. Grundahl, T. Arentoft (U. of Aarhus)
report on behalf of a larger collaboration:

We have observed the afterglow of GRB 080810 (Page et al.
GCN 8080) from the Nordic Optical Telescope (NOT, Roque de los
Muchachos Observatory, La Palma, Spain) using ALFOSC. The
observations started on 10.9899 Aug (10.59 hours after the burst),
when we measure an R-band magnitude of 19.1+/-0.2 (based on
USNO-1B photometry). This  value is in agreement with the slope
decay measured by Rykoff (GCN 8084) implying that no break has
been produced between both observations. This is also consistent
with the magnitudes reported by Burenin et al. (GCN 8088). We
obtained the following coordinates for the afterglow (J2000+/-0.5"):
R.A.: 23:47:10.51
Dec.: +00:19:11.3
This value is slightly off from the value provided by UVOT (Page et
al. GCN 8080) but fully consistent with the one given by Rykoff
(GCN 8084).

We also obtained spectroscopic observations of the afterglow, where
we clearly detect Ly-alpha absorption, a flux drop blueward of the
Lyman break as well as other absorption  lines, including the CIV/CIV
doublet at a redshift of z~3.35, in agreement to what was reported by
Prochaska et al. (GCN 8083) and Burenin et al. (GCN 8088).