English
Related papers

Related papers: The Mass Mixing Length in Convective Stellar Envel…

200 papers

The Doppler line shifts in the spectra of the Sun and stars with effective temperatures from 4800 to 6200 K were measured and the average connective (granulation) velocities were estimated. The absolute scale of the line shifts for the…

Solar and Stellar Astrophysics · Physics 2022-04-05 V. A. Sheminova

One-dimensional (1D) stellar evolution models are widely used across various astrophysical fields, however they are still dominated by important uncertainties that deeply affect their predictive power. Among those, the merging of…

Core overshoot is a large source of uncertainty in constructing stellar models. Whether the amount of overshoot is constant or mass dependent is not completely known, even though models sometimes assume a mass-based trend. In this work we…

Solar and Stellar Astrophysics · Physics 2020-11-25 Lucas S. Viani , Sarbani Basu

The process of convective settling is based on the assumption that a small fraction of the low-entropy downflows sink from the photosphere down to the bottom of the star's envelope convection zone retaining a substantial entropy contrast.…

Solar and Stellar Astrophysics · Physics 2015-07-22 R. Andrássy , H. C. Spruit

We investigate the triggering of star formation and the formation of stellar clusters in molecular clouds that form as the ISM passes through spiral shocks. The spiral shock compresses gas into $\sim$100 pc long main star formation ridge,…

Astrophysics of Galaxies · Physics 2017-10-13 R. Smilgys , I. A. Bonnell

(abridged) Context: Convective motions overshooting to regions that are formally convectively stable cause extended mixing. Aims: To determine the scaling of overshooting depth ($d_{\rm os}$) at the base of the convection zone as a function…

Solar and Stellar Astrophysics · Physics 2020-02-18 Petri J. Käpylä

Empirical star formation laws from the last 20 years are reviewed with a comparison to simulations. The current form in main galaxy disks has a linear relationship between the star formation rate per unit area and the molecular cloud mass…

Astrophysics of Galaxies · Physics 2015-05-27 Bruce G. Elmegreen

The convective collapse of thin magnetic flux tubes in the photospheres of sun-like stars is investigated using realistic models of the superadiabatic upper convection zone layers of these stars. The strengths of convectively stable flux…

Astrophysics · Physics 2009-11-07 S. P. Rajaguru , R. L. Kurucz , S. S. Hasan

Evolved cool stars of various masses are major cosmic engines, delivering substantial mechanical and radiative feedback to the interstellar medium through strong stellar winds and supernova ejecta. These stars play a pivotal role in…

Solar and Stellar Astrophysics · Physics 2024-02-02 Andrea Chiavassa , Kateryna Kravchenko , Jared A. Goldberg

Context. Mixing by convective overshooting has long been suggested to play an important role for the amount of hydrogen available to nuclear burning in convective cores of stars. The best way to model this effect is still debated. Aims. We…

Solar and Stellar Astrophysics · Physics 2022-11-16 F. Kupka , F. Ahlborn , A. Weiss

Mass is constantly being recycled in the universe. One of the most powerful recycling paths is via stellar mass-loss. All stars exhibit mass loss with rates ranging from ~10(-14) to 10(-4) M(sun) yr-1, depending on spectral type, luminosity…

We review progress in numerical simulations of star cluster formation. These simulations involve the bottom-up assembly of clusters through hierarchical mergers, which produces a fractal stellar distribution at young (~0.5 Myr) ages. The…

Astrophysics of Galaxies · Physics 2015-05-14 Cathie Clarke

The atmospheres of cool main-sequence stars are structured by convective flows from the convective envelope that penetrate the optically thin layers and lead to structuring of the stellar atmospheres analogous to solar granulation. The…

Solar and Stellar Astrophysics · Physics 2013-08-27 Benjamin Beeck , Robert H. Cameron , Ansgar Reiners , Manfred Schüssler

The dynamical state of massive clumps is key to our understanding of the formation of massive stars. In this work, we study the kinematic properties of massive clumps using synthetic observations. We have previously compiled a very large…

Astrophysics of Galaxies · Physics 2021-12-22 Zu-Jia Lu , Veli-Matti Pelkonen , Mika Juvela , Paolo Padoan , Troels Haugbølle , Åke Nordlund

The observational consequences of the merger scenario for massive star formation are explored and contrasted with the gradual accumulation of mass by accretion. Protostellar mergers may produce high luminosity infrared flares lasting years…

Astrophysics · Physics 2014-10-13 John Bally , Hans Zinnecker

We present the results of numerical simulations of continuum-driven winds of stars that exceed the Eddington limit and compare these against predictions from earlier analytical solutions. Our models are based on the assumption that the…

Astrophysics · Physics 2009-11-13 A. J. van Marle , S. P. Owocki , N. J. Shaviv

Mixing processes such as convection, overshooting and rotational mixing have long been known to affect the evolutionary properties of low-mass stars. While modeling a 1.2 Msun star, we encountered a semiconvective region outside the fully…

Solar and Stellar Astrophysics · Physics 2015-05-14 V. Silva Aguirre , J. Ballot , A. Serenelli , A. Weiss

The formation pathways for gravitational-wave merger sources are predicted to include common envelope (CE) evolution. Observations of high-mass post-common envelope binaries suggest that energy transfer to the envelope during the CE phase…

Solar and Stellar Astrophysics · Physics 2022-08-31 E. C. Wilson , J. Nordhaus

We present the Stagger-grid, a comprehensive grid of time-dependent, 3D hydrodynamic model atmospheres for late-type stars with realistic treatment of radiative transfer, covering a wide range in stellar parameters. This grid of 3D models…

Solar and Stellar Astrophysics · Physics 2015-06-15 Z. Magic , R. Collet , M. Asplund , R. Trampedach , W. Hayek , A. Chiavassa , R. F. Stein , Å. Nordlund

We present evolutionary models for solar-like stars with an improved treatment of convection that results in a more accurate estimate of the radius and effective temperature. This is achieved by improving the calibration of the…

Solar and Stellar Astrophysics · Physics 2021-04-28 Federico Spada , Pierre Demarque , Friedrich Kupka