English
Related papers

Related papers: Externally Fed Accretion onto Protostars

200 papers

We present results from the first three-dimensional radiation hydrodynamical calculations to follow the collapse of a molecular cloud core beyond the formation of the stellar core. We find the energy released by the formation of the stellar…

Solar and Stellar Astrophysics · Physics 2015-05-18 Matthew R. Bate

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…

Astrophysics · Physics 2009-11-07 P. Hennebelle , A. P. Whitworth , P. P. Gladwin , Ph. Andre

Spherical hydrodynamic models with a polytropic equation of state (EoS) for forming protostars are revisited in order to investigate the so-called luminosity conundrum highlighted by observations. For a molecular cloud (MC) core with such…

Solar and Stellar Astrophysics · Physics 2017-05-31 Yang Gao , Yu-Qing Lou

The star-forming efficiency of dense gas is thought to be set within cores by outflow and radiative feedback. We use magneto-hydrodynamic simulations to investigate the relation between protostellar outflow evolution, turbulence and star…

Astrophysics of Galaxies · Physics 2017-10-04 Stella S. R. Offner , Jonah Chaban

We investigate the role of mass infall in the formation and evolution of protostars. To avoid ad hoc initial and boundary conditions, we consider the infall resulting self-consistently from modeling the formation of stellar clusters in…

Solar and Stellar Astrophysics · Physics 2015-06-22 Paolo Padoan , Troels Haugbølle , Åke Nordlund

The bright maser emission produced by several molecular species at centimeter to long millimeter wavelengths provides an essential tool for understanding the process of massive star formation. Unimpeded by the high dust optical depths that…

Recent observations of protostellar cores suggest that most of the material in the protostellar phase is accreted along streamers. Streamers in this context are defined as velocity coherent funnels of denser material potentially connecting…

Astrophysics of Galaxies · Physics 2024-06-19 Stefan Heigl , Elena Hoemann , Andreas Burkert

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…

Astrophysics · Physics 2009-11-10 Paolo Padoan , Alexei Kritsuk , Michael L. Norman , Ake Nordlund

Star formation efficiency controlled by the protostellar outflow in a single cloud core is investigated by three-dimensional resistive MHD simulations. Starting from the prestellar cloud core, the star formation process is calculated until…

Solar and Stellar Astrophysics · Physics 2015-05-30 Masahiro N. Machida , Tomoaki Matsumoto

We present the calculations of steady, spherical gas outflows from galaxies in an effort to understand the effects of the galaxy mass on the flow properties such as the size of the outflow regions, the efficiency of radiative cooling, and…

Astrophysics · Physics 2007-05-23 Boqi Wang

The collapse of dense cores with different metallicities is studied by hydrodynamical calculations coupled with detailed chemical and radiative processes. For this purpose, we construct a simple chemical network with non-equilibrium…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Kazuyuki Omukai , Takashi Hosokawa , Naoki Yoshida

In order to understand the origin of observed molecular cloud properties, it is critical to understand how clouds interact with their environments during their formation, growth, and collapse. It has been suggested that accretion-driven…

Astrophysics of Galaxies · Physics 2018-12-21 Juan C. Ibáñez-Mejía , Mordecai-Mark Mac Low , Ralf S. Klessen , Christian Baczynski

We review recent advances in the analytical and numerical modeling of the star formation rate in molecular clouds and discuss the available observational constraints. We focus on molecular clouds as the fundamental star formation sites,…

A protostellar jet and outflow are calculated for \sim 270 yr following the protostar formation using a three dimensional magnetohydrodynamics simulation, in which both the protostar and its parent cloud are spatially resolved. A…

Solar and Stellar Astrophysics · Physics 2015-06-23 Masahiro N. Machida

We use one-dimensional two-zone time-dependent accretion disk models to study the long-term evolution of protostellar disks subject to mass addition from the collapse of a rotating cloud core. Our model consists of a constant surface…

Solar and Stellar Astrophysics · Physics 2015-05-18 Zhaohuan Zhu , Lee Hartmann , Charles Gammie

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…

Solar and Stellar Astrophysics · Physics 2018-02-01 Michael Kuffmeier , Søren Frimann , Sigurd S. Jensen , Troels Haugbølle

We address the classical problem of star accretion onto a supermassive central gaseous object in a galactic nucleus. The resulting supermassive central gas-star object is assumed to be located at the centre of a dense stellar system for…

Astrophysics · Physics 2016-08-30 Pau Amaro-Seoane , Rainer Spurzem

The formation and evolution of a circumstellar disk in magnetized cloud cores is investigated from prestellar core stage until sim 10^4 yr after protostar formation. In the circumstellar disk, fragmentation first occurs due to gravitational…

Solar and Stellar Astrophysics · Physics 2015-05-27 Masahiro N. Machida , Shu-ichiro Inutsuka , Tomoaki Matsumoto

The growing process of both a young protostar and a circumstellar disk is investigated. Viscous evolution of a disk around a single star is considered with a model where a disk increases its mass by dynamically accreting envelope and…

Earth and Planetary Astrophysics · Physics 2015-06-16 Takuya Ohtani , Toru Tsuribe

The distribution of protostar masses is studied for core-environment systems whose duration of infall follows a waiting-time distribution. Each core-environment system has a continuous density profile with no barrier to mass flow. The core…

Astrophysics of Galaxies · Physics 2014-11-20 Philip C. Myers