Results 11 to 20 of about 345 (250)
Turbulence-supported Massive Star Envelopes
The Astrophysical Journal Letters, 2023 The outer envelopes of massive ( M ≳ 10 M _⊙ ) stars exhibit large increases in opacities from forests of lines and ionization transitions (particularly from iron and helium) that trigger near-surface convection zones. One-dimensional (1D) models predict
William C. Schultz +2 more
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Asteroseismic Investigation on KIC 10526294 to Probe Convective Core Overshoot Mixing
The Astrophysical Journal, 2023 In the overshoot mixing model with an exponentially decreasing diffusion coefficient, the initial value of the diffusion coefficient plays a crucial role.
Qian-Sheng Zhang +3 more
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Overstable Convective Modes in a Polytropic Stellar Atmosphere
The Astrophysical Journal, 2023 Within the convection zone of a rotating star, the presence of the Coriolis force stabilizes long-wavelength convective modes. These modes, which would have been unstable if the star lacked rotation, are called overstable convective modes or thermal ...
Bradley W. Hindman, Rekha Jain
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Grids of Wolf–Rayet Stars Using MESA with the k − ω Model: From 25 to 120 M ⊙ at Z = 0.02
The Astrophysical Journal Supplement Series, 2023 To explore overshoot mixing and rotational mixing beyond the convective core during the core He-burning phase in massive stars, we computed a grid of stellar models, both rotating and nonrotating, with the k − ω model at Z = 0.02, covering a mass range ...
Zhi Li, Yan Li
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Three-dimensional Simulations of Massive Stars. II. Age Dependence
The Astrophysical Journal, 2023 We present 3D full star simulations, reaching up to 90% of the total stellar radius, for three 7 M _⊙ stars of different ages: zero-age main sequence (ZAMS), mid–main sequence (midMS), and terminal-age main sequence (TAMS).
R. Vanon +4 more
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Plumes in Stellar Convection Zones [PDF]
Annals of the New York Academy of Sciences, 2000 Abstract: All numerical simulations of compressible convection reveal the presence of strong downward directed flows. Thanks to helioseismology, such plumes have now also been detected at the top of the solar convection zone, on supergranular scales. Their properties may be crudely described by adopting Taylor's turbulent entrainment hypothesis, whose
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Convection Zones in Stellar Atmospheres.
The Astrophysical Journal, 1962 In following the evolution of stars to the cooler regions of giants in the H-R diagram, core solutions are fitted with the atmospheric solutions; this parameter is the constant that joins the pressure and temperature at the end of the ionization zone. The distribution of this parameter in the H-R diagram was studied by computing atmospheric models. The
K. S. Krishna Swamy, R. S. Kushwaha
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One Zone Modeling of Irregular Variability of Stellar Convective Envelope [PDF]
International Astronomical Union Colloquium, 1993 AbstractOne zone modeling of the irregular variability of red super-giants is intended with regard to the nonlinear coupling of finite amplitude pulsation with convection. The nonlocal mixing length is employed for the evaluation of the convective flux, the turbulent pressure and the turbulent power of temperature fluctuations. The radial pulsation and
Unno, W., Xiong, D.-R.
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Torsional magnetic tube waves in stellar convection zones [PDF]
Astronomy & Astrophysics, 2003 An analytic approach to the generation of torsional magnetic tube waves in stellar convection zones is presented. The waves are produced in a thin, vertically oriented magnetic flux tube embedded in a magnetic field-free, turbulent and compressible external medium and are excited by external turbulent flows.
M. W. Noble +2 more
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An attempt to calibrate core overshooting using the seismic properties of low-mass stars
EPJ Web of Conferences, 2015 The sizes of stellar convective cores remain uncertain because of our poor understanding of the interface between convective and radiative zones. The very high precision of the seismic data provided by the CoRoT and Kepler space missions offers a great ...
Deheuvels S. +7 more
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