Related papers: High Accretion Rate during Class 0 Phase due to Ex…
We present a simple physical mechanism that can account for the observed stellar mass spectrum for masses $\ms \simgreat 0.5 \solm$. The model depends solely on the competitive accretion that occurs in stellar clusters where each star's…
During the formation of the large scale structure of the Universe, matter accretes onto high density peaks. Accreting collisionless dark matter (DM) forms caustics around them, while accreting collisional baryonic matter (BM) forms…
The main accretion phase of star formation is investigated in clouds with different metallicities in the range of 0 \le Z \le Z_\odot, resolving the protostellar radius. Starting from a near-equilibrium prestellar cloud, we calculate the…
Accretion rates of order 10^-8 M_\odot/yr are observed in young protostars of approximately a solar mass with evidence of circumstellar disks. The accretion rate is significantly lower for protostars of smaller mass, approximately…
Close-in super-Earths having radii 1--4 $R_\oplus$ may possess hydrogen atmospheres comprising a few percent by mass of their rocky cores. We determine the conditions under which such atmospheres can be accreted by cores from their parent…
Neutron stars in low mass X-ray binaries exhibit oscillations during thermonuclear bursts, attributed to asymmetric brightness patterns on the burning surfaces. All models that have been proposed to explain the origin of these asymmetries…
The origin of the supermassive black holes that power the most distant quasars observed is largely unknown. One hypothesis is that they grew rapidly from intermediate-mass seeds (~100 M_sun) left by the first stars. However, some previous…
Using zoom-simulations carried out with the adaptive mesh-refinement code RAMSES with a dynamic range of up to $2^{27} \approx 1.34 \times 10^8$ we investigate the accretion profiles around six stars embedded in different environments…
Recent theoretical works suggest that the pebble accretion process is important for planet formation in protoplanetary disks, because it accelerates the growth of planetary cores. While several observations reveal axisymmetric sharp gaps in…
We present the first results from two-dimensional simulations of radiatively-efficient accretion of metal-free gas onto intermediate-mass black holes. We fix the shape of the spectral energy distribution of the radiation produced near the…
Cosmology models predict that external accretion shocks form in the outer region of galaxy clusters due to supersonic gas infall from filaments and voids in the cosmic web. They are characterized by high sonic and Alfv\'enic Mach numbers,…
A model of core-clump accretion with equally likely stopping describes star formation in the dense parts of clusters, where models of isolated collapsing cores may not apply. Each core accretes at a constant rate onto its protostar, while…
We have performed fully 3D simulations of the collapse of molecular cloud cores which obey the logatropic equation of state. By following the collapse of these cores from states of near hydrodynamic equilibrium, we are able to produce…
The accretion phase of star formation is investigated in magnetically-dominated clouds that have an initial subcritical mass-to-flux ratio. We employ nonideal magnetohydrodynamic simulations that include ambipolar diffusion and ohmic…
We present numerical simulations of the evolution of low-mass, isothermal, molecular cores which are subjected to an increase in external pressure $P\xt$. If $P\xt$ increases very slowly, the core approaches instability quite…
Classical T Tauri stars (cTTs) accrete from their circumstellar disk. The material falls onto the stellar surface, producing an accretion shock, which generates veiling in a star's spectra. In addition, the shock causes a localized…
We investigate prestellar core formation and accretion based on three-dimensional hydrodynamic simulations. Our simulations represent local $\sim 1$pc regions within giant molecular clouds where a supersonic turbulent flow converges,…
We present estimates for the accretion rates in 13 X--ray bursting sources which exhibit photospheric expansion, basing on theoretical models of stationary, radiatively driven winds from neutron stars. The relatively high values obtained,…
The formation of the most massive quasars observed at high redshifts requires extreme inflows of gas down to the length scales of the central compact object. Here, we estimate the maximum inflow rate allowed by gravity down to the surface…
Supermassive black holes are not only common in the present-day galaxies, but billion solar masses black holes also powered $z\geq 6$ quasars. One efficient way to form such black holes is the collapse of a massive primordial gas cloud into…