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Related papers: Episodic outbursts during brown dwarf formation

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We present new numerical simulations in the thin-disk approximation which characterize the burst mode of protostellar accretion. The burst mode begins upon the formation of a centrifugally balanced disk around a newly formed protostar. It…

Astrophysics · Physics 2008-11-26 E. I. Vorobyov , Shantanu Basu

The formation of brown dwarfs via encounters between proto-stars has been confirmed with high-resolution numerical simulations with a restricted treatment of the thermal conditions. The new results indicate that young brown dwarfs (BDs)…

Astrophysics · Physics 2010-11-11 Sijing Shen , James Wadsley

We present simulation results for the formation and long-term evolution of a primordial protostellar disk harbored by a first star. Using a 2+1D nonaxisymmetric thin disk numerical simulation, together with a barotropic relation for the…

Astrophysics of Galaxies · Physics 2015-06-11 A. L. DeSouza , E. I. Vorobyov , S. Basu

Context. Young Stellar Objects (YSOs) are observed to undergo powerful accretion events known as FU Orionis outbursts (FUors). Such events of episodic accretion are now considered to be common during low mass star formation, wherein the…

Solar and Stellar Astrophysics · Physics 2025-05-07 Kundan Kadam , Eduard Vorobyov , Peter Woitke , Manuel Güdel

Masses and radii of transiting brown dwarfs can be measured directly in contrast to isolated field brown dwarfs, whose mass and radius inferences are model dependent. Therefore, transiting brown dwarfs are a testbed for the interior and…

Earth and Planetary Astrophysics · Physics 2026-04-02 Sagnick Mukherjee , Jonathan J. Fortney , Theron W. Carmichael , C. Evan Davis , Daniel P. Thorngren

Dwarf galaxies in the Local Group appear to be stripped of their gas within 270 kpc of the host galaxy. Color-magnitude diagrams of these dwarfs, however, show clear evidence of episodic star formation (\Delta{}t ~ a few Gyr) over cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Matthew Nichols , Doug Lin , Joss Bland-Hawthorn

Young low-mass stars are characterized by ejection of collimated outflows and by circumstellar disks which they interact with through accretion of mass. The accretion builds up the star to its final mass and is also believed to power the…

Solar and Stellar Astrophysics · Physics 2015-05-28 S. Orlando , F. Reale , G. Peres , A. Mignone

The early evolution of protostellar disks with metallicities in the $Z=1.0-0.01~Z_\odot$ range was studied with a particular emphasis on the strength of gravitational instability and the nature of protostellar accretion in low-metallicity…

Solar and Stellar Astrophysics · Physics 2020-07-01 E. I. Vorobyov , V. G. Elbakyan , K. Omukai , T. Hosokawa , R. Matsukoba , M. Guedel

An investigation of the magnetospheric accretion and outflow signatures in sub-stellar objects is a natural extension of similar studies conducted on classical T Tauri stars (CTTS), and helps understand if brown dwarfs (BDs) follow the same…

Solar and Stellar Astrophysics · Physics 2013-07-08 B. Riaz

Variable accretion in young stellar objects reveals itself photometrically and spectroscopically over a continuum of timescales and amplitudes. Most dramatic are the large outbursts (e.g., FU Ori, V1647 Ori, and EX Lup type events), but…

Solar and Stellar Astrophysics · Physics 2023-11-20 William J. Fischer , Lynne A. Hillenbrand , Gregory J. Herczeg , Doug Johnstone , Ágnes Kóspál , Michael M. Dunham

We suggest that low-mass hydrogen-burning stars like the Sun should sometimes form with massive extended discs; and we show, by means of radiation hydrodynamic simulations, that the outer parts of such discs (R>100 AU) are likely to…

Astrophysics · Physics 2009-11-13 Dimitris Stamatellos , David Hubber , Anthony Whitworth

Episodic star formation cycles in both high- and low-redshift galaxies have gained more and more evidence. This paper aims to understand the detailed physical processes behind such behaviors and investigate how such an episodic star-forming…

Astrophysics of Galaxies · Physics 2025-12-02 Yuqian Gui , Dandan Xu , Haoyi Wang , Xuelun Mei , Enci Wang , Cheng Li , Stijn Wuyts

Recent observations show a strong correlation between stellar mass and accretion rate in young stellar and sub-stellar objects, with the scaling $\dot{M}_{acc} \propto M_*^2$ holding over more than four orders of magnitude in accretion…

Astrophysics · Physics 2009-11-11 R. D. Alexander , P. J. Armitage

We perform two-dimensional axially symmetric radiation-hydrodynamic simulations to assess the impact of outflows and radiative force feedback from massive protostars by varying when the protostellar outflow starts, the ratio of ejection to…

Solar and Stellar Astrophysics · Physics 2016-11-23 Rolf Kuiper , Neal J. Turner , Harold W. Yorke

According to the magnetospheric accretion scenario, young low-mass stars are surrounded by circumstellar disks which they interact with through accretion of mass. The accretion builds up the star to its final mass and is also believed to…

Solar and Stellar Astrophysics · Physics 2014-01-03 S. Orlando , F. Reale , G. Peres , A. Mignone

Following our recent work devoted to the effect of accretion on the pre-main-sequence evolution of low-mass stars, we perform a detailed analysis of episodic excursions of low-mass protostars in the Hertzsprung-Russell (H-R) diagram…

Solar and Stellar Astrophysics · Physics 2019-01-09 Vardan G. Elbakyan , Eduard I. Vorobyov , Christian Rab , D. M. -A. Meyer , Manuel Güdel , Takashi Hosokawa , Harold Yorke

Episodic accretion has been used to explain the wide range of protostellar luminosities, but its origin and influence on the star forming process are not yet fully understood. We present an ALMA survey of N$_2$H$^+$ ($1-0$) and HCO$^+$…

A protoplanetary disk typically forms a dead zone near its midplane at the distance of a few au from the central protostar. Accretion through such a magnetically layered disk can be intrinsically unstable and has been associated with…

Solar and Stellar Astrophysics · Physics 2021-03-10 Kundan Kadam , Eduard Vorobyov , Ágnes Kóspál

The evolution of protostellar outflows is investigated under different mass accretion rates in the range $\sim10^{-5}-10^{-2} {\rm M}_\odot$ yr$^{-1}$ with three-dimensional magnetohydrodynamic simulations. A powerful outflow always appears…

Astrophysics of Galaxies · Physics 2020-10-21 Masahiro N. Machida , Takashi Hosokawa

We extend the one-dimensional, two-zone models of long-term protostellar disk evolution with infall of Zhu et al. to consider the potential effects of a finite viscosity in regions where the ionization is too low for the magnetorotational…

Solar and Stellar Astrophysics · Physics 2015-06-12 Jaehan Bae , Lee Hartmann , Zhaohuan Zhu , Charles Gammie