We investigate the specific angular momentum (sAM) j((star)((star) proportional to M-star(alpha) with an index alpha varying from alpha = 0.3 to alpha = 0.5, from log M-star/M-circle dot = 8 to log... Show moreWe investigate the specific angular momentum (sAM) j((star)((star) proportional to M-star(alpha) with an index alpha varying from alpha = 0.3 to alpha = 0.5, from log M-star/M-circle dot = 8 to log M-star/M-circle dot = 10.5. The UDF sample supports a redshift evolution (j) over tilde (star proportional to) (1 + z)(a), with a = 0.27(-0.56)(+0.42) which is consistent with the (1 + z)(-0.5) expectation from a universe in expansion. The scatter of the sAM sequence is a strong function of the dynamical state with logj vertical bar(M star) proportional to 0.65(-0.08)(+0.06) x log(V-max/sigma), where sigma is the velocity dispersion at 2R(e). In TNG50, SFGs also form a (j) over tilde (star) - M-star (V/sigma) plane, but it correlates more with galaxy size than with morphological parameters. Our results suggest that SFGs might experience a dynamical transformation, and lose their sAM, before their morphological transformation to becoming passive via either merging or secular evolution. Show less
The formation and evolution of galaxies is fundamentally driven by the formation of new stars out of cold gas. Observations of young stars in distant galaxies in the early universe, such as we can... Show moreThe formation and evolution of galaxies is fundamentally driven by the formation of new stars out of cold gas. Observations of young stars in distant galaxies in the early universe, such as we can see in the Hubble Ultra Deep Field, have unveiled how the cosmic star formation rate density evolves. Yet, while the effect of star formation—the young stars—has been mapped in ever-increasing detail, the cause—the cold molecular gas that fuels star formation—has been elusive. This thesis presents an observational study of the cold interstellar medium of distant galaxies in the early universe, using the most sensitive submillimeter telescope to date, the Atacama Large Millimeter Array, together with new integral-field spectrographs, such as the Multi Unit Spectroscopic Explorer on the Very Large Telescope. It unveils the physical properties of star-forming galaxies and their molecular gas reservoirs, and describes the evolution of the cosmic molecular gas density—the fuel for star formation. Show less
