[vsnet-grb-info 14486] GRB 140206A: NOT redshift

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15800
SUBJECT: GRB 140206A: NOT redshift
DATE:    14/02/06 21:52:48 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani at dark-cosmology.dk>

D. Malesani, D. Xu, J. P. U. Fynbo (DARK/NBI), A. de Ugarte Postigo 
(IAA/CSIC and DARK/NBI), S. Schulze (PUC and MCSS), A. Finoguenov (U. 
Helsinki), P. Jakobsson (U. Iceland), A. Melandri (INAF/OABr), A. 
Cucchiara (NASA/GSFC), report on behalf of a larger collaboration:

We observed the field of GRB 140206A (Lien et al., GCN 15784; Gotz et 
al., GCN 15785; Troja et al., GCN 13243) with the Nordic Optical 
Telescope (NOT) equipped with ALFOSC. Observations started at 19:56 UT 
on February 6 (i.e., 12.66 hr after the burst).

We first obtained a 100-s image in R band.  We clearly detect the source 
reported in Oksanen et al. (GCN 15786). The source has faded to 19.15 
+/- 0.10 mag (Vega magnitude), based on nearby USNO stars.

We aso obtained an optical spectrum, with a total exposure of 2 x 1800 
s, using grism #4 and a blocking filter covering the wavelength range 
3750 - 9000 AA at a resolution of 8.1 AA. The mid exposure time is 13.6 
hr after the GRB.

We detect several absorption lines which we interpret as due to Lyalpha, 
Si II, C II, C IV, Al II, Fe II at a common redshift of 2.73.

This measurement is not consistent with the predicted theoretical value 
by Ruffini et al. (GCN 15794).

We thank Carlos Perez, John Teltin, and Amanda Djupvik (NOT) for 
excellent support with the observations.