Related papers: Mass Limits to Primordial Star Formation from Prot…
Feedback from massive stars plays an important role in the formation of star clusters. Whether a very massive star is born early or late in the cluster formation timeline has profound implications for the star cluster formation and assembly…
We study feedback during massive star formation using semi-analytic methods, considering the effects of disk winds, radiation pressure, photoevaporation and stellar winds, while following protostellar evolution in collapsing massive gas…
Recent numerical simulations have shown that the unstable disk within the central regime of the primordial gas cloud fragments to form multiple protostars on several scales. Their evolution depends on the mass accretion phenomenon,…
We perform a three dimensional radiation hydrodynamics simulation to investigate the formation of first stars from initial collapse of a primordial gas cloud to formation and growth of protostars. The simulation is integrated until 0.1 Myrs…
First, the formation of first objects driven by dark matter is revisited by high-resolution hydrodynamic simulations. It is revealed that dark matter haloes of ~10^4M_sun can produce first luminous objects with the aid of dark matter cusps.…
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 first stars form in dark matter halos of masses ~10^6 M_sun as suggested by an increasing number of numerical simulations. Radiation feedback from these stars expels most of the gas from their shallow potential well of their surrounding…
Formation of massive stars by accretion requires a high accretion rate of > 10^-4 M_sun/yr to overcome the radiation pressure barrier of the forming stars. Here, we study evolution of protostars accreting at such high rates, by solving the…
We consider whether the maximum mass of first stars is imposed by the protostellar spin, i.e., by the so-called $\Omega\Gamma$-limit, which requires the sum of the radiation and centrifugal forces at the stellar surface be smaller than the…
We describe how star formation is expected to proceed in the early metal-free Universe, focusing on the very first generations of stars. We then discuss how the star formation process may change as the effects of metallicity, external…
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…
We investigate how the removal of interstellar material by stellar feedback limits the efficiency of star formation in molecular clouds and how this determines the shape of the mass function of young star clusters. In particular, we derive…
Star formation generally proceeds inside-out, with overdense regions inside protostellar cores collapsing rapidly and progressively less dense regions following later. Consequently, a small protostar will form early in the evolution of a…
Stellar feedback in the form of radiation pressure and magnetically-driven collimated outflows may limit the maximum mass that a star can achieve and affect the star-formation efficiency of massive pre-stellar cores. Here we present a…
Star cluster formation is unlikely to be a sudden event: instead, matter will flow to a cluster's formation site over an extended period, even as stars form and inject energy to the region. A cluster's gaseous precursor must persist under…
Understanding the origin of high-mass stars is central to modern astrophysics. We shed light on this problem with simulations using a novel, adaptive-mesh, ray-tracing algorithm. These simulations consistently follow the gravitational…
A model for massive stars is constructed by piecing together evolutionary algorithms for the protostellar structure, the environment, the inflow and the radiation feedback. We investigate specified accretion histories of constant,…
We model the formation of high-mass stars, specifying the accretion rate in terms of the instantaneous and final mass of the star, the ambient pressure of the star-forming region and the form of polytropic pressure support of the…
Massive protostars attain high luminosities as they are actively accreting and the radiation pressure exerted on the gas in the star's atmosphere may launch isotropic high-velocity winds. These winds will collide with the surrounding gas…
I describe a turbulence-inspired model for the stellar initial mass function which includes feedback and self-regulation via protostellar outflows. A new aspect of the model provides predictions of the star formation rate in molecular…