The Formation and Evolution of Bulges and Disks in High-Redshift Galaxies

Abstract

Most present-day galaxies with stellar masses of about 10^11 M⊙ show no ongoing star formation and are dense spheroids. Ten billion years ago, at a redshift of z~2, similarly massive galaxies were typically forming stars at rates of hundreds of solar masses per year. It is debated how star formation ceased, on which timescales, and how this “quenching” relates to the emergence of dense spheroids. This Ph.D. thesis presents results on the growth of galactic components in typical star-forming galaxies and delivers a major step forward in understanding how these galaxies stopped their star formation. The core of these results is based on observations, in particular with the Hubble Space Telescope and the Very Large Telescope in Chile. We have also developed and investigated numerical and analytical models to interpret our observations.