English
Related papers

Related papers: Episodic accretion: the interplay of infall and di…

200 papers

The growth process of proto-planets can be sped-up by accreting a large number of solid, pebble-sized objects that are still present in the protoplanetary disc. It is still an open question on how efficient this process works in realistic…

Earth and Planetary Astrophysics · Physics 2018-08-29 Giovanni Picogna , Moritz H. R. Stoll , Wilhelm Kley

We study the impact of accretion from protoplanetary discs on stellar evolution of AFG-type stars. We use a simplified disc model computed using the Two-Pop-Py code that contains the growth and drift of dust particles in the protoplanetary…

Solar and Stellar Astrophysics · Physics 2020-09-16 R. Hoppe , M. Bergemann , B. Bitsch , A. Serenelli

We simulate the formation and collapse of prestellar cores at few-AU resolution in a set of radiation-magneto-hydrodynamic simulations of giant molecular clouds (GMCs) using the grid-based code RAMSES-RT. We adopt, for the first time to our…

Astrophysics of Galaxies · Physics 2023-05-10 Chong-Chong He , Massimo Ricotti

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

We have carried out hydro-dynamical simulations to investigate the formation and evolution of protostar and circumstellar disks from the prestellar cloud. As the initial state, we adopt the molecular cloud core with two non-dimensional…

Solar and Stellar Astrophysics · Physics 2015-03-19 Yusuke Tsukamoto , Masahiro N. Machida

The formation and evolution of the circumstellar disk in unmagnetized molecular clouds is investigated using three-dimensional hydrodynamic simulations from the prestellar core until the end of the main accretion phase. In collapsing…

Solar and Stellar Astrophysics · Physics 2015-05-14 Masahiro N. Machida , Shu-ichiro Inutsuka , Tomoaki Matsumoto

We discuss the factors influencing the formation and gravitational fragmentation of protostellar discs. We start with a review of how observations of prestellar cores can be analysed statistically to yield plausible initial conditions for…

Solar and Stellar Astrophysics · Physics 2016-05-19 A. P. Whitworth , O. D. Lomax

Irradiation of the accretion disc causes reflection signatures in the observed X-ray spectrum, encoding important information about the disc structure and density. A Type I X-ray burst will strongly irradiate the accretion disc and alter…

High Energy Astrophysical Phenomena · Physics 2021-11-03 J. Speicher , D. R. Ballantyne , P. C. Fragile

At least half of a protostar's mass is accreted in the Class 0 phase, when the central protostar is deeply embedded in a dense, infalling envelope. We present the first systematic search for outbursts from Class 0 protostars in the Orion…

We present radiation transfer (RT) simulations of evolutionary sequences of massive protostars forming from massive dense cores in environments of high surface densities. The protostellar evolution is calculated with a detailed multi-zone…

Astrophysics of Galaxies · Physics 2015-06-18 Yichen Zhang , Jonathan C. Tan , Takashi Hosokawa

We present a study of the evolution of the inner few astronomical units of protoplanetary disks around low-mass stars. We consider nearby stellar groups with ages spanning from 1 to 11 Myr, distributed into four age bins. Combining…

The surroundings of massive protostars constitute an accretion disc which has numerically been shown to be subject to fragmentation and responsible for luminous accretion-driven outbursts. Moreover, it is suspected to produce close binary…

Solar and Stellar Astrophysics · Physics 2017-12-06 D. M. -A. Meyer , R. Kuiper , W. Kley , K. G. Johnston , E. Vorobyov

Even today in our Galaxy, stars form from gas cores in a variety of environments, which may affect the properties of resulting star and planetary systems. Here we study the role of pressure, parameterized via ambient clump mass surface…

Astrophysics of Galaxies · Physics 2015-06-23 Yichen Zhang , Jonathan C. Tan

In this paper, perturbations of an accretion disk by a star orbiting around a black hole are studied. We report on a numerical experiment, which has been carried out by using a parallel-machine code originally developed by D\"{o}nmez…

Astrophysics · Physics 2009-09-29 Orhan Donmez

Fragmentation of protostellar disks controls the growth of protostars and plays a key role in determining the final mass of newborn stars. In this paper, we investigate the structure and gravitational stability of the protostellar disks in…

Astrophysics of Galaxies · Physics 2015-06-18 Kei E. I. Tanaka , Kazuyuki Omukai

Many disc-type post-asymptotic giant branch (post-AGB) stars are chemically peculiar, showing underabundances of refractory elements in their photospheres that correlate with condensation temperature. The aim of this paper is to investigate…

Solar and Stellar Astrophysics · Physics 2019-09-04 Glenn-Michael Oomen , Hans Van Winckel , Onno Pols , Gijs Nelemans

We introduce a prescription for the luminosity from accreting protostars into smoothed particle hydrodynamics simulation, and apply the method to simulations of five primordial minihalos generated from cosmological initial conditions. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Rowan J. Smith , Simon C. O. Glover , Paul C. Clark , Thomas Greif , Ralf S. Klessen

We investigate the formation of protostellar clusters during the collapse of dense molecular cloud cores with a focus on the evolution of potential and kinetic energy, the degree of substructure, and the early phase of mass segregation. Our…

Solar and Stellar Astrophysics · Physics 2015-06-03 Philipp Girichidis , Christoph Federrath , Richard Allison , Robi Banerjee , Ralf Klessen

(abridged) Context: Both observations and simulations of embedded protostars have progressed rapidly in recent years. Bringing them together is an important step in advancing our knowledge about the earliest phases of star formation. Aims:…

Solar and Stellar Astrophysics · Physics 2016-02-17 Søren Frimann , Jes K. Jørgensen , Troels Haugbølle

The filamentary nature of accretion streams found around embedded sources suggest that protostellar disks experience heterogenous infall from the star-forming environment, consistent with the accretion behavior onto star-forming cores in…

Earth and Planetary Astrophysics · Physics 2022-04-06 Aleksandra Kuznetsova , Jaehan Bae , Lee Hartmann , Mordecai-Mark Mac Low
‹ Prev 1 8 9 10 Next ›