Stellar models with mixing length and T(tau) relations calibrated on 3D convection simulations

Abstract

(abridged) The calculation of the thermal stratification in the superadiabatic layers of stellar models with convective envelopes is a long standing problem of stellar astrophysics, and has a major impact on predicted observational properties like radius and effective temperature. The Mixing Length Theory, almost universally used to model the superadiabatic convective layers, contains effectively one free parameter to be calibrated --alpha(ml)-- whose value controls the resulting effective temperature. Here we present the first self-consistent stellar evolution models calculated by employing the atmospheric temperature stratification, Rosseland opacities, and calibrated variable alpha(ml) (dependent on effective temperature and surface gravity) from a large suite of three-dimensional radiation hydrodynamics simulations of stellar convective envelopes and atmospheres for solar stellar composition (Trampedach et al. 2013). From our calculations (with the same composition of the radiation hydrodynamics simulations), we find that the effective temperatures of models with the hydro-calibrated variable alpha(ml) display only minor differences, by at most ~30-50 K, compared to models calculated at constant solar alpha(ml). The depth of the convective regions is essentially the same in both cases. We have also analyzed the role played by the hydro-calibrated T(tau) relationships in determining the evolution of the model effective temperatures, when compared to alternative T(tau) relationships often used in stellar model computations. The choice of the T(tau) can have a larger impact than the use of a variable alpha(ml) compared to a constant solar value. We found that the solar semi-empirical T(tau) by Vernazza et al. (1981) provides stellar model effective temperatures that agree quite well with the results with the hydro-calibrated relationships.

arXiv comment6 pages, 3 figures, accepted for publication in A&A

References in corpus (23)

• A large stellar evolution database for population synthesis studies. I. Scaled solar models and isochrones
• Low Temperature Opacities
• Up-dated opacities from the Opacity Project
• The Stagger-grid: A Grid of 3D Stellar Atmosphere Models - I. Methods and General Properties
• Red Giant Branch stars: the theoretical framework
• A uniform asteroseismic analysis of 22 solar-type stars observed by Kepler
• Improvements to stellar structure models, based on a grid of 3D convection simulations. II. Calibrating the mixing-length formulation
• A Grid of 3D Stellar Atmosphere Models of Solar Metallicity: I. General Properties, Granulation and Atmospheric Expansion
• The Stagger-grid: A grid of 3D stellar atmosphere models - III. The relation to mixing-length convection theory
• A critical investigation on the discrepancy between the observational and theoretical Red Giant luminosity function "Bump"
• Dynamical Mass Constraints on Low-Mass Pre-Main-Sequence Stellar Evolutionary Tracks: An Eclipsing Binary in Orion with a 1.0 Msun Primary and an 0.7 Msun Secondary
• Improvements to Stellar Structure Models, Based on a Grid of 3D Convection Simulations. I. $T(\tau )$-Relations
• Models of alpha Centauri A and B with and without seismic constraints: time dependence of the mixing-length parameter
• Stellar models with the ML2 theory of convection
• Modelling the components of binaries in Hyades: The dependence of the mixing-length parameter on stellar mass
• Variation of Stellar Envelope Convection and Overshoot with Metallicity
• Surface convection and red giants radii measurements
• Stellar Envelope Convection calibrated by Radiation Hydrodynamics Simulations: Influence on Globular Clusters Isochrones
• Theory of stellar convection: Removing the Mixing-Length Parameter
• The Effect of Metallicity-Dependent T-tau Relations on Calibrated Stellar Models
• Stellar models for very low mass main sequence stars: the role of model atmospheres
• Comparing the Effect of Radiative Transfer Schemes on Convection Simulations
• Helium-Abundance and Other Composition Effects on the Properties of Stellar Surface Convection in Solar-like Main-sequence Stars

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