Abstract
We present the properties of molecular gas in the host galaxy of GRB 080207,
located at $z$ = 2.086, based on the CO(32) emission line. We find this galaxy
to be rich in molecular gas with a mass of $1.1 10^11 M_ødot$ and a
molecular gas mass fraction of $\sim$0.5, typical of star forming galaxies with
similar stellar masses and redshifts. With a $SFR_FIR$ of 260 $M_ødot
yr^-1$, its molecular-gas-depletion timescale is 0.43 Gyr, which is near
the peak of the depletion timescale distribution of the star-forming galaxies
at similar redshifts. The molecular gas properties of the GRB host appears to
follow the scaling relations of the general star-forming galaxy population with
similar stellar masses, star formation rates, and redshifts, which is in
contrast with the proposed molecular gas deficiency in GRB host galaxies. We
also show that the H$\alpha$ emission line from the galaxy contains a narrow
and a broad component, with an offset of 470 km/s from each other. The narrow
component matches the CO emission well in the velocity space. The broad
component, with a FWHM larger than 900 km/s, is associated with a significant
and uncommonly strong outflow of gas from the galaxy.
Users
Please
log in to take part in the discussion (add own reviews or comments).