Friday, April 20, 2012

1204.4236 (Bernardo Cervantes-Sodi et al.)

The spin of late-type galaxies at redshifts $z\le 1.2$    [PDF]

Bernardo Cervantes-Sodi, X. Hernandez, Ho Seong Hwang, Changbom Park, Damien Le Borgne
We study the evolution of the galactic spin using data of high redshift galaxies in the fields of the Great Observatories Origins Deep Survey (GOODS). Through simple dynamical considerations we estimate the spin for the disc galaxies in our sample and find that its distribution is consistent with that found for nearby galaxies. Defining a dimensionless angular momentum parameter for the disc component of the galaxies ($\lambda_{d}$), we do not find signs of evolution in the redshift range $0.4 \leq z \leq 1.2$. We find that the mass and environmental dependence of the spin of our high redshift galaxies are similar to that of low-$z$ galaxies; showing a strong dependence on mass, in the sense that low-mass systems present higher $\lambda_{d}$ values than high-mass galaxies, with no significant dependence on the environmental density. These results lead us to conclude that, although individual disc galaxies might occasionally suffer from strong evolution, they evolve in such a way that the overall spin distribution of the galactic population remains constant from $z\sim1$ to the present epoch.
View original: http://arxiv.org/abs/1204.4236

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