Related papers: Galaxy Evolution: Internally or Externally Driven?
Star formation occurs in hierarchical patterns in both space and time. Galaxies form large regions on the scale of the interstellar Jeans length and these large regions apparently fragment into giant molecular clouds and cloud cores in a…
Quantification of the Galaxy's star formation history involves both the duration and the rate of formation, with these parameters being known with different precision for different populations. The early rate of star formation is knowable…
We use simple analytic reasoning to identify physical processes that drive the evolution of the cosmic star formation density in cold dark matter universes. Based on our analysis, we formulate a model to characterise the redshift dependence…
We examine the origin of clustercentric gradients in the star formation rates and colors of rich cluster galaxies within the context of a simple model where clusters are built through the ongoing accretion of field galaxies. The model…
Based on a simulation of galaxy formation in the standard cosmological model, we suggest that a consistent picture for Gamma-Ray Bursts and star formation may be found that is in broad agreement with observations: GRBs preferentially form…
The properties of galaxies are strongly correlated with their environment, with red galaxies dominating galaxy clusters and blue galaxies dominating the general field. However, not all field galaxies are young: studies of the colors, line…
Differences in the stellar populations of galaxies can be used to quantify the effect of environment on the star formation history. We target a sample of early-type galaxies from the Sloan Digital Sky Survey in two different environmental…
The environment within the inner few hundred parsecs of the Milky Way, known as the "Central Molecular Zone" (CMZ), harbours densities and pressures orders of magnitude higher than the Galactic Disc; akin to that at the peak of cosmic star…
The environment is known to affect the formation and evolution of galaxies considerably best visible through the well-known morphology-density relationship. In this paper we study the effect of environment on the evolution of early-type…
The environment is known to affect the formation and evolution of galaxies considerably best visible through the well-known morphology-density relationship. We study the effect of environment on the evolution of early-type galaxies for a…
The age and chemical composition of the stars in present-day galaxies carry important clues about their star formation processes. The latest generation of population synthesis models have allowed to derive age and stellar metallicity…
Star formation in massive galaxies is quenched at some point during hierarchical mass assembly. To understand where and when the quenching processes takes place, we study the evolution of the total star formation rate per unit total halo…
The concept that stars form in the modern era began some 60 years ago with the key observation of expanding OB associations. Now we see that these associations are an intermediate scale in a cascade of hierarchical structures that begins on…
These notes collect together current work on the effect of the environment on galaxy formation and evolution. They are broken into four distinct parts. The first deals with the observational debate surrounding the question of whether…
We investigate the star-formation properties of dynamically relaxed galaxy clusters as a function of cluster mass for 308 low-redshift clusters drawn from the Sloan Digital Sky Survey (SDSS) C4 cluster catalog. It is important to establish…
Star formation lies at the center of a web of processes that drive cosmic evolution: generation of radiant energy, synthesis of elements, formation of planets, and development of life. Decades of observations have yielded a variety of…
Galaxy star formation rates (SFRs) are sensitive to the local environment; for example, the high-density regions at the cores of dense clusters are known to suppress star formation. It has been suggested that galaxy transformation occurs…
A fundamental quest of modern astronomy is to locate the earliest galaxies and study how they influenced the intergalactic medium a few hundred million years after the Big Bang. The abundance of star-forming galaxies is known to decline…
We show that various milestones of high-redshift galaxy formation, such as the formation of the first stars or the complete reionization of the intergalactic medium, occurred at different times in different regions of the universe. The…
Spectroscopic observations of distant cosmological sources continue to exhibit a surprising result; that the chemical abundance of the universe seems to be approximately solar for the observed sources at redshifts of 5, 6, and even 7, even…