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Related papers: Calibration of the Mixing-Length Theory for Convec…

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Two-dimensional hydrodynamical simulations were made to calibrate the mixing length parameter for modeling red giant's convective envelope. As was briefly reported in Asida & Tuchman (97), a comparison of simulations starting with models…

Astrophysics · Physics 2009-10-31 S. M. Asida

A proposed setting for thermonuclear (Type Ia) supernovae is a white dwarf that has gained mass from a companion to the point of carbon ignition in the core. In the early stages of carbon burning, called the simmering phase, energy released…

Solar and Stellar Astrophysics · Physics 2025-01-29 Brendan Boyd , Alan Calder , Dean Townsley , Michael Zingale

We present a detailed spectroscopic analysis of 115 helium-line (DB) and 28 cool, He-rich hydrogen-line (DA) white dwarfs based on atmosphere fits to optical spectroscopy and photometry. We find that 63% of our DB population show hydrogen…

Solar and Stellar Astrophysics · Physics 2018-05-02 Benoit Rolland , Pierre Bergeron , Gilles Fontaine

The accurate flux calibration of observational data is vital for astrophysics and cosmology because absolute flux uncertainties of stellar standards propagate into scientific results. With the ever higher precision achieved by telescopic…

The predictive accuracy of density functional theory (DFT) for alloy formation enthalpies is often limited by intrinsic energy resolution errors, particularly in ternary phase stability calculations. In this work, we present a machine…

Materials Science · Physics 2025-03-10 Sergei I. Simak , Erna K. Delczeg-Czirjak , Olle Eriksson

$\Lambda$-Warm Dark Matter (WDM) has been proposed as alternative scenario to $\Lambda$ cold dark matter (CDM), motivated by discrepancies at the scale of dwarf galaxies, with less small-scale power and realized by collisionless particles…

Astrophysics of Galaxies · Physics 2018-08-08 Alice Chau , Lucio Mayer , Fabio Governato

3D model atmospheres for giants, dwarfs, and white dwarfs, computed with the CO5BOLD code and part of the CIFIST grid, have been used for spectroscopic and asteroseismic studies. Unlike existing plane-parallel 1D structures, these…

Solar and Stellar Astrophysics · Physics 2015-06-16 P. -E. Tremblay , H. -G. Ludwig , B. Freytag , M. Steffen , E. Caffau

Condensable species are crucial in shaping planetary climate. A wide range of planetary climate systems involve understanding non-dilute condensable substances and their influence on climate dynamics. There has been progress on large-scale…

Earth and Planetary Astrophysics · Physics 2021-12-22 Xianyu Tan , Maxence Lefevre , Raymond Pierrehumbert

One of the largest sources of uncertainty in the computation of globular cluster isochrones and hence in the age determination of globular clusters is the lack of a rigorous description of convection. Therefore, we calibrated the…

Astrophysics · Physics 2009-10-31 Bernd Freytag , Maurizio Salaris

We present an approach that combines the local density approximation (LDA) and the dynamical mean-field theory (DMFT) in the framework of the full-potential linear augmented plane waves (FLAPW) method. Wannier-like functions for the…

The hydrogen envelope is the outermost layer of a DA white dwarf; it makes up the entirety of the stellar photosphere, and yet its typical extent is difficult to model theoretically and remains poorly observationally constrained. As a…

Solar and Stellar Astrophysics · Physics 2026-03-05 Stefan M. Arseneau , J. J. Hermes , Maria E. Camisassa , Roberto Raddi , Evan B. Bauer

Melting properties are critical for designing novel materials, especially for discovering high-performance, high-melting refractory materials. Experimental measurements of these properties are extremely challenging due to their high melting…

Materials Science · Physics 2024-08-19 Li-Fang Zhu , Fritz Koermann , Qing Chen , Malin Selleby , Joerg Neugebauer , and Blazej Grabowski

We describe CATKE, a parameterization for fluxes associated with small-scale or "microscale" ocean turbulent mixing on scales between 1 and 100 meters. CATKE uses a downgradient formulation that depends on a prognostic turbulent kinetic…

We use holography in order to study the entropy of thermal CFTs on (1+1)-dimensional curved backgrounds that contain horizons. Starting from the metric of the BTZ black hole, we perform explicit coordinate transformations that set the…

High Energy Physics - Theory · Physics 2021-09-29 Dimitrios Giataganas , Nikolaos Tetradis

Brown dwarfs are essential targets for understanding planetary and sub-stellar atmospheres across a wide range of thermal and chemical conditions. As surveys continue to probe ever deeper, and as observing capabilities continue to improve,…

Earth and Planetary Astrophysics · Physics 2021-11-24 Shih-Yun Tang , Tyler D. Robinson , Mark S. Marley , Natasha E. Batalha , Roxana Lupu , L. Prato

Polluted white dwarfs (WDs) with small surface convection zones deposit significant concentrations of heavy elements to the underlying radiative interior, presumably driving thermohaline convection. Current models of polluted WDs frequently…

Solar and Stellar Astrophysics · Physics 2025-03-28 Imogen G. Cresswell , Adrian E. Fraser , Evan B. Bauer , Evan H. Anders , Benjamin P. Brown

We study convective overshooting by means of local 3D convection calculations. Using a mixing length model of the solar convection zone (CZ) as a guide, we determine the Coriolis number (Co), which is the inverse of the Rossby number, to be…

Astrophysics · Physics 2015-06-24 P. J. Käpylä , M. J. Korpi , M. Stix , I. Tuominen

We present numerical simulations, using two complementary setups, of rotating Boussinesq thermal convection in a three-dimensional Cartesian geometry with misaligned gravity and rotation vectors. This model represents a small region at a…

Solar and Stellar Astrophysics · Physics 2020-02-19 Laura K. Currie , Adrian J. Barker , Yoram Lithwick , Matthew K. Browning

We use single-cluster Monte Carlo simulations to study the role of topological defects in the three-dimensional classical Heisenberg model on simple cubic lattices of size up to $80^3$. By applying reweighting techniques to time series…

High Energy Physics - Lattice · Physics 2009-10-22 Christian Holm , Wolfhard Janke

We describe a new multi-colour proper motion survey for cool white dwarfs (CWDs). The observational database consists of ~300 digitally scanned Schmidt plates in ESO/SERC field 287. The entire survey procedure, from the raw Schmidt plate…

Astrophysics · Physics 2009-10-31 R. A. Knox , M. R. S. Hawkins , N. C Hambly