Related papers: An Evolutionary Timeline for High-mass Star Format…
We perform calculations of pre-main sequence evolution of stars from 1 to $85 M_{\odot}$ with growing accretion rates $\dot{M}$. The values of $\dot{M}$ are taken equal to a constant fraction $\tilde{f}$ of the rates of the mass outflows…
The discovery of large numbers of young low-mass stars and brown dwarfs over the last decade has made it possible to investigate star formation and early evolution in a previously unexplored mass regime. In this review, we begin by…
We review recent theoretical results on the formation of the first stars in the universe, and emphasize related open questions. In particular, we discuss the initial conditions for Population III star formation, as given by variants of the…
Star clusters stand at the intersection of much of modern astrophysics: the interstellar medium, gravitational dynamics, stellar evolution, and cosmology. Here we review observations and theoretical models for the formation, evolution, and…
Our knowledge of the initial conditions and early stages of high mass star formation is very limited. We will review recent surveys of regions in the early stages of massive star formation using molecular tracers of high density and dust…
Mass is constantly being recycled in the universe. One of the most powerful recycling paths is via stellar mass-loss. All stars exhibit mass loss with rates ranging from ~10(-14) to 10(-4) M(sun) yr-1, depending on spectral type, luminosity…
Stars mostly form in groups consisting of a few dozen to several ten thousand members. For 30 years, theoretical models provide a basic concept of how such star clusters form and develop: they originate from the gas and dust of collapsing…
The formation environment of stars in massive stellar clusters is similar to the environment of stars forming in galaxies at a redshift of 1 - 3, at the peak star formation rate density of the Universe. As massive clusters are still forming…
Massive stars (with mass m_* > 8 solar masses) are fundamental to the evolution of galaxies, because they produce heavy elements, inject energy into the interstellar medium, and possibly regulate the star formation rate. The individual star…
Magnetic fields play a crucial role at all stages of the formation of low mass stars and planetary systems. In the final stages, in particular, they control the kinematics of in-falling gas from circumstellar discs, and the launching and…
The physical mechanism that allows massive stars to form is a major unsolved problem in astrophysics. Stars with masses $\gtsim 20$ $\msun$ reach the main sequence while still embedded in their natal clouds, and the immense radiation output…
Star formation involves the flow of gas and dust within molecular clouds into protostars and young stellar objects (YSOs) due to gravity. Along the way, these flows are shaped significantly by many other mechanisms, including pressure,…
The chemical abundances in the atmosphere of a star provide unique information about the gas from which that star formed, and, modulo processes that are not important for the vast majority of stars, such as mass transfer in close binary…
The timescale for star formation, a measure of how quickly neutral gas is being converted to stars, is considerably longer than typical dynamical timescales associated with a galactic disk. For purposes of modeling galaxy evolution,…
Star formation occurs on physical scales corresponding to individual star forming regions, typically of order ~100 parsecs in size, but current observational facilities cannot resolve these scales within field galaxies beyond the local…
When did galaxies start forming stars? What is the role of distant galaxies in galaxy formation models and the epoch of reionization? What are the conditions in typical star-forming galaxies at redshifts >~4? Why is galaxy evolution…
The history of galaxy formation via star formation and stellar mass assembly rates is now known with some certainty, yet the connection between high redshift and low redshift galaxy populations is not yet clear. By identifying and studying…
Young stars on their way to the ZAMS evolve in significantly different ways depending on mass. While the theoretical and observational properties of low- and intermediate-mass stars are rather well understood and/or empirically tested, the…
Recent studies of the nearest star-forming clouds of the Galaxy at submillimeter wavelengths with the Herschel Space Observatory have provided us with unprecedented images of the initial conditions and early phases of the star formation…
All measurements of cosmic star formation must assume an initial distribution of stellar masses -- the stellar initial mass function -- in order to extrapolate from the star-formation rate measured for typically rare, massive stars (> 8…