相关论文: Blocking metal accretion onto population III stars…
We study cosmological simulations of early structure formation, including non-equilibrium molecular chemistry, metal pollution from stellar evolution, transition from population III (popIII) to population II (popII) star formation,…
Planet accretion onto solar type stars may significantly change the stellar atmospheric abundances of 6Li and 7Li if it takes place after the star has arrived at the main sequence. Ingestion of planets at an earlier phase will not affect…
The winds of low-mass stars carry away angular momentum and impact the atmospheres of surrounding planets. Determining the properties of these winds is necessary to understand the mass-loss history of the star and the evolution of…
Competitive accretion occurs when stars in a cluster accrete from a shared reservoir of gas. The competition arises due to the relative attraction of stars as a function of their mass and location in the cluster. The low relative motions of…
Cosmological numerical simulations of galaxy evolution show that accretion of metal-poor gas from the cosmic web drives the star formation in galaxy disks. Unfortunately, the observational support for this theoretical prediction is still…
Current simulations indicate that the first stars were formed predominantly in binary systems. The study of the contribution of the first accreting binary systems to the reionization and heating of the intergalactic medium requires the…
We study the formation of very metal-poor stars under protostellar radiative feedback effect. We use cosmological simulations to identify low-mass dark matter halos and star-forming gas clouds within them. We then follow protostar formation…
Both gas accretion (infall) and winds (outflow) change a galaxy's metallicity and gas fraction, lowering the effective yield. Low effective yields in galaxies with rotation speeds < 120 km/s have been widely interpreted as the onset of…
Population III stars form in groups due to the fragmentation of primordial gas. While uniform magnetic fields have been shown to support against fragmentation in present day star formation, it is unclear whether realistic k^3/2 primordial…
Pop III stars are typically massive stars of primordial composition forming at the centers of the first collapsed dark matter structures. Here we estimate the optimal X-ray emission in the early universe for promoting the formation of Pop…
In regions of star formation, protostars and newborn stars accrete mass from their natal clouds. These clouds are threaded by magnetic fields with a strength characterized by the plasma beta---the ratio of thermal and magnetic pressures.…
Following the renewed interest for axions as a dark matter component, we revisit the effects of energy loss by axion emission on the evolution of the first generation of stars. These stars with zero metallicity are supposed to be massive,…
We model the evolution of the abundances of light elements in carbon-enhanced metal-poor (CEMP) stars, under the assumption that such stars are formed by mass transfer in a binary system. We have modelled the accretion of material ejected…
The first generations of stars ionised and enriched their host galaxies and seeded the growth of massive black holes. Models often assume that Pop III stellar masses in different minihaloes are stochastic realisations of a single universal…
Young stars are expected to gain most of their mass by accretion from a disk that forms around them as a result of angular momentum conservation in the collapsing protostellar cloud. Accretion initially proceeds at high rates of…
Tidal Disruption Events (TDEs) release enormous amounts of energy, offering a promising avenue for detecting Population III (Pop III) stars. However, the radiative properties of TDEs of Pop III stars have so far been studied only…
A number of recently discovered extrasolar planet candidates have surprisingly small orbits, which may indicate that considerable orbital migration takes place in protoplanetary systems. A natural consequence of orbital migration is for a…
The origin of low alpha/Fe ratios in some metal-poor stars, so called low-alpha stars, is discussed. It is found that most of low-alpha stars in the Galaxy are on the main-sequence. This strongly suggests that these stars suffered from…
We investigate the upper stellar mass limit set by radiative feedback by the forming star with various accretion rates and metallicities. To this end, we numerically solve the structures of both a protostar and its surrounding accretion…
During a giant eruption of a very massive star in the binary system, the companion star can accrete a large amount of mass that can change its properties and potentially its subsequent evolution. The effect depends on the companion mass,…