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Related papers: A Solution to the Protostellar Accretion Problem

200 papers

We have measured the present accretion rate of roughly 800 low-mass (~1-1.4 Mo) pre-Main Sequence stars in the field of Supernova 1987A in the Large Magellanic Cloud (LMC, Z~0.3 Zo). It is the first time that this fundamental parameter for…

Astrophysics · Physics 2009-11-10 Martino Romaniello , Massimo Robberto , Nino Panagia

A star acquires much of its mass by accreting material from a disc. Accretion is probably not continuous but episodic. We have developed a method to include the effects of episodic accretion in simulations of star formation. Episodic…

Astrophysics of Galaxies · Physics 2015-05-27 Dimitris Stamatellos , Anthony Whitworth , David Hubber

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…

Solar and Stellar Astrophysics · Physics 2017-09-20 Eduard Vorobyov , Vardan Elbakyan , Takashi Hosokawa , Yuya Sakurai , Manuel Guedel , Harold Yorke

Massive stars likely form by accretion and the evolutionary track of an accreting forming star corresponds to what is called the birthline in the HR diagram. The shape of this birthline is quite sensitive to the evolution of the entropy in…

Solar and Stellar Astrophysics · Physics 2015-12-23 Lionel Haemmerlé , Patrick Eggenberger , Georges Meynet , André Maeder , Corinne Charbonnel

We analyse protostellar mass accretion rates from numerical models of star formation based on gravoturbulent fragmentation, considering a large number of different environments. To within one order of magnitude, the mass accretion rate is…

Astrophysics · Physics 2009-11-10 S. Schmeja , R. S. Klessen

We argue that one of the basic assumptions of the Bondi accretion process, that the accreting object has zero pressure, might not hold in many galaxies because of the pressure exerted by stellar winds of star orbiting the central super…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Shlomi Hillel , Noam Soker

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…

Earth and Planetary Astrophysics · Physics 2019-01-23 Yuki A. Tanaka , Yusuke Tsukamoto

We compute the accretion efficiency of small solids, with radii 1 cm $\le$ Rs $\le$ 10 m, on planets embedded in gaseous disks. Planets have masses 3 $\le$ Mp $\le$ 20 Earth masses (Me) and orbit within 10 AU of a solar-mass star. Disk…

Earth and Planetary Astrophysics · Physics 2024-06-06 Gennaro D'Angelo , Peter Bodenheimer

The collapse of massive molecular clumps can produce high mass stars, but the evolution is not simply a scaled-up version of low mass star formation. Outflows and radiative effects strongly hinder the formation of massive stars via…

Astrophysics · Physics 2007-05-23 Harold W. Yorke

The formation of star clusters involves the growth of smaller, gas-rich subclusters through accretion of gas from the giant molecular cloud within which the subclusters are embedded. The two main accretion mechanisms responsible for this…

Astrophysics of Galaxies · Physics 2023-03-29 Jeremy Karam , Alison Sills

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

The origin of the population of very massive stars observed within $\sim 0.4$ pc of the supermassive black hole in the Galactic Centre is a mystery. Tidal forces from the black hole would likely inhibit {\it in situ} star formation whilst…

Astrophysics of Galaxies · Physics 2020-09-02 Melvyn B. Davies , Doug N. C. Lin

The massive black hole in our galactic center, Sgr A*, accretes only a small fraction of the gas available at its Bondi radius. The physical processes determining this accretion rate remain unknown, partly due to a lack of observational…

High Energy Astrophysical Phenomena · Physics 2015-03-18 Michael McCourt , Ann-Marie Madigan

Pebble accretion refers to the assembly of rocky planet cores from particles whose velocity dispersions are damped by drag from circumstellar disc gas. Accretion cross-sections can approach maximal Hill-sphere scales for particles whose…

Earth and Planetary Astrophysics · Physics 2018-08-15 Jonathan W. Lin , Eve J. Lee , Eugene Chiang

We develop a model for the outer gravitationally unstable regions of accretion disks around massive black holes, for primeval or solar abundances. First we study star formation and evolution in a purely gaseous marginally unstable disk, and…

Astrophysics · Physics 2009-10-31 Suzy Collin , Jean-Paul Zahn

Compact objects are expected to exist in the accretion disks of supermassive black holes (SMBHs) in active galactic nuclei (AGNs), and in the presence of such a dense environment ($\sim 10^{14}\,{\rm cm^{-3}}$), they will form a new kind of…

High Energy Astrophysical Phenomena · Physics 2021-04-21 Jian-Min Wang , Jun-Rong Liu , Luis C. Ho , Pu Du

The role of convection in the gas-dust accretion disk around a young star is studied. The evolution of a Keplerian disk is modeled using the Pringle equation, which describes the time variations of the surface density under the action of…

Solar and Stellar Astrophysics · Physics 2020-03-11 Ya. N. Pavlyuchenkov , A. V. Tutukov , L. A. Maksimova , E. I. Vorobyov

We determine the observational signatures of protostellar cores by coupling two-dimensional radiative transfer calculations with numerical hydrodynamical simulations that predict accretion rates that both decline with time and feature…

Astrophysics of Galaxies · Physics 2015-06-03 Michael M. Dunham , Eduard I. Vorobyov

MHD models and the observation of accretion streamers confirmed that protostars can undergo late accretion events after the initial collapse phase. To provide better constraints, we study the evolution of stellar masses in MHD simulations…

Solar and Stellar Astrophysics · Physics 2023-03-10 M. Kuffmeier , S. S. Jensen , T. Haugbølle

We present the results of fully 3-D hydrodynamic simulations of the gravitational collapse of isolated, turbulent molecular cloud cores. Starting from initial states of hydrostatic equilibrium, we follow the collapse of both singular and…

Astrophysics · Physics 2009-11-07 M. A. Reid , R. E. Pudritz , J. Wadsley
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