Related papers: Mixing and Accretion in lambda Bootis Stars
The ability to resolve all processes which drive galaxy formation is one of the most fundamental goals in extragalactic astronomy. While star formation rates and the merger history are now measured with increasingly high certainty, the role…
We discuss the importance of accretion in calculating disk models for young stellar objects. In particular, we show that a disk inner rim, irradiated by both the star and the accretion shocks at the stellar surface, can naturally explain…
Low-mass protostars may accrete most of their material through short-lived episodes of rapid disk accretion; yet until recently evolutionary tracks for these protostars assumed only constant or slowly-varying accretion. Important initial…
A large fraction of white dwarf stars shows photospheric chemical composition polluted by heavy elements accreted from a debris disk. Such debris disks result from the tidal disruption of rocky planetesimals which had survived to whole…
We describe the main-sequence evolution of a rotating 9 $M_\odot$ star. Its interior rotation profile is determined by the redistribution of angular momentum through the meridian circulation and through the shear turbulence generated by the…
The formation of massive black holes and their coevolution with host galaxies are pivotal areas of modern astrophysics. Spherical accretion onto a central point mass serves as a foundational framework in cosmological simulations,…
An isolated star moving supersonically through a uniform gas accretes material from its gravitationally-induced wake. The rate of accretion is set by the accretion radius of the star and is well-described by classical Bondi-Hoyle-Lyttleton…
The majority of massive stars reside in binary systems, which are expected to experience mass transfer during their evolution. However, so far the conditions under which mass transfer leads to a common envelope, and thus possibly to a…
Accretion of interplanetary dust onto gas giant exoplanets is considered. Poynting-Robertson drag causes dust particles from distant reservoirs to slowly inspiral toward the star. Orbital simulations for the three-body system of the star,…
Accreting main-sequence stars expand significantly when the mass accretion timescale is much shorter than their thermal timescales. This occurs during mass transfer from an evolved giant star onto a main-sequence companion in a binary…
Convection in the cores of massive stars becomes anisotropic when they rotate. This anisotropy leads to a misalignment of the thermal gradient and the thermal flux, which in turn results in baroclinicity and circulation currents in the…
Mass transfer between non-degenerate stars is a fundamental but still poorly understood process in binary evolution. The commonly used rotationally limited accretion prescription in detailed binary evolution simulations that account for…
Star formation is intimately linked to the dynamical evolution of molecular clouds. Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass via accretion from the surrounding cloud…
Mass accretion onto (proto-)stars at high accretion rates > 10^-4 M_sun/yr is expected in massive star formation. We study the evolution of massive protostars at such high rates by numerically solving the stellar structure equations. In…
The accretion process in young stellar objects (YSOs) is fundamental to the formation of stellar systems. This process governs the star's mass assembly, the transfer of angular momentum, and the shaping of the protoplanetary disc, thereby…
Low mass stars (< 2-2.5 M_sun) exhibit, at all the stages of their evolution, signatures of processes that require challenging modeling beyond the standard stellar theory. In this paper we focus on their peculiarities while they climb the…
The aim of this paper is to provide a measurement of the mass accretion rate in a large, complete sample of objects in the core of the star forming region Rho-Oph. The sample includes most of the objects (104 out of 111) with evidence of a…
The pre-main-sequence evolution of low-mass stars and brown dwarfs is studied numerically starting from the formation of a protostellar/proto-brown dwarf seed and taking into account the mass accretion onto the central object during the…
We present numerical hydrodynamical modeling of the effects of a giant planet or brown dwarf companion orbiting within the extended atmosphere and wind formation zone of an approximately solar-mass Mira variable star. The large-scale,…
It is speculated that the accretion of material onto young protostars is episodic. We present a computational method to include the effects of episodic accretion in radiation hydrodynamic simulations of star formation. We find that during…