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Related papers: Episodic outbursts during brown dwarf formation

200 papers

We present a brief summary of the Single Degenerate Scenario for the progenitors of Type Ia Supernovae in which it is assumed that a low mass carbon-oxygen white dwarf is growing in mass as a result of accretion from a secondary star in a…

Solar and Stellar Astrophysics · Physics 2012-10-24 S. Starrfield , C. Iliadis , F. X. Timmes , W. R. Hix , W. D. Arnett , C. Meakin , W. M. Sparks

In the classical grouping of large magnitude episodic variability of young accreting stars, FUORs outshine their stars by a factor of $\sim$ 100, and can last for up to centuries; EXORs are dimmer, and last months to a year. A disc Hydrogen…

Brown dwarfs, which occupy a fuzzy gap in mass between stars and planets, appear to be common both in the solar neighborhood and in star-forming regions. Their origin is a topic of significant current interest and debate. Some astronomers…

Astrophysics · Physics 2007-05-23 Ray Jayawardhana

The relation between the mass accretion rate onto the circumstellar disc and the rate of mass ejection by magnetically driven winds is investigated using three-dimensional magnetohydrodynamics simulations. Using a spherical cloud core with…

Solar and Stellar Astrophysics · Physics 2017-07-05 Yuko Matsushita , Masahiro N. Machida , Yuya Sakurai , Takashi Hosokawa

Recent discoveries of extrasolar planets at small orbital radii, or with significant eccentricities, indicate that interactions between massive planets and the disks of gas and dust from which they formed are vital for determining the final…

Astrophysics · Physics 2009-10-31 Philip J. Armitage , Brad M. S. Hansen

Motivated by recent observations which detect an outer boundary for starless cores, and evidence for time-dependent mass accretion in the Class 0 and Class I protostellar phases, we reexamine the case of spherical isothermal collapse in the…

Astrophysics · Physics 2009-11-10 E. I. Vorobyov , Shantanu Basu

Very low-mass stars and brown dwarfs can undergo pulsational instability excited by central deuterium burning during the initial phases of their evolution. We present the results of evolutionary and nonadiabatic linear stability models that…

Astrophysics · Physics 2007-05-23 Francesco Palla , Isabelle Baraffe

We investigate how the external medium surrounding prestellar cores affects the star formation process by conducting three-dimensional resistive magnetohydrodynamic simulations. The initial cores follow critical Bonnor-Ebert profiles and…

Astrophysics of Galaxies · Physics 2025-10-29 Shingo Nozaki , Masahiro N. Machida

Evidence abounds that young stellar objects undergo luminous bursts of intense accretion that are short compared to the time it takes to form a star. It remains unclear how much these events contribute to the main-sequence masses of the…

Star cluster formation is unlikely to be a sudden event: instead, matter will flow to a cluster's formation site over an extended period, even as stars form and inject energy to the region. A cluster's gaseous precursor must persist under…

Astrophysics of Galaxies · Physics 2017-12-06 Christopher D. Matzner

The outpouring of radiation during an X-ray burst can affect the properties of accretion discs around neutron stars: the corona can cool and collapse, the inner regions can be bled away due to enhanced accretion, and the additional heating…

High Energy Astrophysical Phenomena · Physics 2022-11-16 D. R. Ballantyne

We argue that the outbursts of the FU Orionis stars occur on timescales which are much longer than expected from the standard disc instability model with \alpha_{c} \gtrsim 10^{-3}. The outburst, recurrence, and rise times are consistent…

Astrophysics · Physics 2009-11-10 O. M. Matthews , R. Speith , G. A. Wynn

The origin of brown dwarfs (BDs) is an important component of the theory of star formation, because BDs are approximately as numerous as solar mass stars. It has been suggested that BDs originate from the gravitational fragmentation of…

Astrophysics · Physics 2007-05-23 Paolo Padoan , Alexei Kritsuk , Michael Norman , Ake Nordlund

The timing of formation for the first planetesimals determines the mode of planetary accretion and their geophysical and compositional evolution. Astronomical observations of circumstellar discs and Solar System geochronology provide…

Earth and Planetary Astrophysics · Physics 2022-11-17 A. Bonsor , T. Lichtenberg , J. Drazkowska , A. M. Buchan

We present a near-infrared study of accretion and outflow activity in 6 Class 0/I proto-brown dwarfs (proto-BDs) using VLT/SINFONI spectroscopy and spectro-imaging observations. The spectra show emission in several [FeII] and H$_{2}$ lines…

Solar and Stellar Astrophysics · Physics 2021-01-06 B. Riaz , J. Bally

We investigate the impact of bursts in star formation on the predictions of one-zone chemical evolution models, adopting oxygen (O), iron (Fe), and strontium (Sr), as representative $\alpha$, iron-peak, and s-process elements, respectively.…

Astrophysics of Galaxies · Physics 2019-11-11 James W. Johnson , David H. Weinberg

We combine the output of hydrodynamical simulations of Population III star cluster formation with stellar evolution models, and calculate the evolution of protostars experiencing variable mass accretion rates due to interactions within a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Rowan J. Smith , Takashi Hosokawa , Kazuyuki Omukai , Simon C. O. Glover , Ralf S. Klessen

Giant Eruptions (GEs) are episodic high-rate mass loss events that massive stars experience in the late stage of evolutions before exploding as a core-collapse supernova. If it occurs in a binary system, the companion star can accrete part…

Solar and Stellar Astrophysics · Physics 2025-04-29 Bhawna Mukhija , Amit Kashi

We investigate the occurrence of accretion bursts, dust accumulation, and the prospects for planetesimal formation in a gravitationally unstable magnetized protoplanetary disk with globally suppressed but episodically triggered…

Earth and Planetary Astrophysics · Physics 2025-04-21 Indrani Das , Eduard Vorobyov , Shantanu Basu

The protostellar outflow mechanism operates for a significant fraction of the pre-main sequence phase of a solar mass star and is thought to have a key role in star and perhaps even planet formation. This energetic mechanism manifests…

Solar and Stellar Astrophysics · Physics 2014-07-01 E. T. Whelan