[vsnet-grb-info 14156] GRB 131108A: Redshift from 10.4m GTC
GCN Circulars
gcncirc at capella2.gsfc.nasa.gov
Sat Nov 9 14:35:08 JST 2013
TITLE: GCN CIRCULAR
NUMBER: 15470
SUBJECT: GRB 131108A: Redshift from 10.4m GTC
DATE: 13/11/09 05:35:00 GMT
FROM: Antonio de Ugarte Postigo at IAA-CSIC <deugarte at iaa.es>
A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), C.C. Thoene (IAA-CSIC),
J. Gorosabel (IAA-CSIC), R. Sanchez-Ramirez (IAA-CSIC),
J.P.U. Fynbo (DARK/NBI), N.R. Tanvir (U. Leicester),
A. Cabrera-Lavers (ULL/IAC) and A. Garcia (ULL/IAC) report on
behalf of a larger collaboration:
We have observed the afterglow of the Fermi-LAT GRB 131108A (Racusin
et al. GCN 15464, Hurley et al. GCN 15466, Stroh et al. GCN 15468, Gorosabel
et al. GCN 15469) with the 10.4m GTC telescope at Roque de los Muchachos
Observatory (La Palma, Spain) starting at 04:50 UT (8.13 hr after the burst).
The observation consisted of 3x600 s and was performed with the R1000B
grism, that covers the range from 3700 to 7500 A at a resolution of ~1000.
Observations were performed with a poor seeing of ~2.2". The afterglow is
detected in the acquisition frame with at a magnitude of r=18.9, as compared
with the SDSS.
A preliminary reduction of the spectrum shows a strong trace and is
characterised by a strong Ly-alpha absorption as well as absorption features
which include SII, SiII, SiII*, OI, CII, SiIV, CIV and AlII at a common redshift of
z=2.40, which we identify as the redshift of the GRB.
More information about the vsnet-grb-info
mailing list