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Related papers: Some Thoughts on the Convective Urca Process

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We examine the evolution of low-mass star and brown dwarf eclipsing binaries. These objects are rapid rotators and are believed to shelter large magnetic fields. We suggest that reduced convective efficiency, due to fast rotation and large…

Astrophysics · Physics 2008-12-18 Gilles Chabrier , Jose Gallardo , Isabelle Baraffe

The detection of heavy elements at suprasolar abundances in the atmospheres of some accreting white dwarfs in cataclysmic variables, coupled with the high temperatures needed to produce these elements requires explosive thermonuclear…

Solar and Stellar Astrophysics · Physics 2015-06-22 Edward M. Sion

The final stages of the evolution of electron--degenerate ONe cores, resulting from carbon burning in ``heavy weight'' intermediate--mass stars ($8 M_{\sun}\la M \la 11 M_{\sun}$) and growing in mass, either from carbon burning in a shell…

Astrophysics · Physics 2009-11-10 J. L. Gutierrez , R. Canal , E. Garcia-Berro

Double white dwarf (WD) merger process and their post-merger evolution are important in many fields of astronomy, such as supernovae, gamma-ray bursts, gravitational waves, etc. The evolutionary outcomes of double ultra-massive WD merger…

Solar and Stellar Astrophysics · Physics 2023-08-22 Chengyuan Wu , Heran Xiong , Zhanwen Han , Bo Wang

In accreting WDs approaching the Chandrasekhar limit, hydrostatic carbon burning precedes the dynamical breakout. During this \textit{simmering} phase, $e-$captures are energetically favored in the central region of the star, while…

Solar and Stellar Astrophysics · Physics 2022-02-23 Luciano Piersanti , Eduardo Bravo , Oscar Straniero , Sergio Cristallo , Inmaculada Dominguez

The process of carbon burning is vital to understanding late stage stellar evolution of massive stars and the conditions of certain supernovae. Carbon burning is a complex problem, involving quantum tunnelling and nuclear molecular states.…

Nuclear Theory · Physics 2025-09-18 Grant Close , Paul Stevenson , Alexis Diaz-Torres

It has been proposed that mixing induced by convective overshoot can disrupt the inward propagation of carbon deflagrations in super-asymptotic giant branch stars. To test this theory, we study an idealized model of convectively bounded…

We analyze temporal evolution of the number of accreting white dwarfs with shell hydrogen burning in semidetached and detached binaries. We consider a stellar system in which star formation lasts for 10 Gyr with a constant rate, as well as…

High Energy Astrophysical Phenomena · Physics 2015-05-19 L. R. Yungelson

The evolution of circumstellar discs is influenced by their surroundings. The relevant processes include external photoevaporation due to nearby stars, and dynamical truncations. The impact of these processes on disc populations depends on…

Astrophysics of Galaxies · Physics 2025-10-03 Francisca Concha-Ramírez , Maite J. C. Wilhelm , Simon Portegies Zwart

We investigate crystallization-driven convection in carbon-oxygen white dwarfs. We present a version of the mixing length theory (MLT) that self-consistently includes the effects of thermal diffusion and composition gradients, and provides…

Solar and Stellar Astrophysics · Physics 2024-07-01 Matias Castro-Tapia , Andrew Cumming , J. R. Fuentes

In this paper, four sets of evolutionary models are computed with different values of the mixing length parameter $\alpha_{\rm p}$ and the overshooting parameter $\delta_{\rm ov}$. The properties of the convective cores and the convective…

Solar and Stellar Astrophysics · Physics 2015-05-14 Jin Jie , Chunhua Zhu , Guoliang Lv

(Abridged abstract) We explore the formation of ultra-massive (M_{\rm WD} \gtrsim 1.05 M_\sun$), carbon-oxygen core white dwarfs resulting from single stellar evolution. We also study their evolutionary and pulsational properties and…

A brief review is given of neutrino emission processes in dense matter, with particular emphasis on recent developments. These include direct Urca processes for nucleons and hyperons, which can give rise to rapid energy loss from the…

Astrophysics · Physics 2016-08-30 C. J. Pethick , Vesteinn Thorsson

[Shortened] The 12C + 12C fusion reaction has been the subject of considerable experimental efforts to constrain uncertainties at temperatures relevant for stellar nucleosynthesis. In order to investigate the effect of an enhanced carbon…

Solar and Stellar Astrophysics · Physics 2015-06-03 M. E. Bennett , R. Hirschi , M. Pignatari , S. Diehl , C. Fryer , F. Herwig , A. Hungerford , K. Nomoto , G. Rockefeller , F. X. Timmes , M. Wiescher

The uncertainties in the modelling of some important inputs of stellar evolution must be taken into account for a correct interpretation, both of the HR diagrams of individual stars, and of the integrated colors, of stellar clusters. After…

Astrophysics · Physics 2007-05-23 F. D'Antona

In this review I give a summary of the state-of-the-art for what concerns the chemo-dynamical numerical modelling of galaxies in general and of dwarf galaxies in particular. In particular, I focus my attention on (i) initial conditions;…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 S. Recchi

The modelling of massive star evolution is a complex task, and is very sensitive to the way physical processes (such as convection, rotation, mass loss, etc.) are included in stellar evolution code. Moreover, the very high observed fraction…

Solar and Stellar Astrophysics · Physics 2016-12-19 Cyril Georgy , Raphael Hirschi , Sylvia Ekström

In spite of the great effort made in the last decades to improve our understanding of stellar evolution, significant uncertainties still remain due to our poor knowledge of some complex physical processes that still require an empirical…

Solar and Stellar Astrophysics · Physics 2015-06-12 Alessandro Bressan , Paola Marigo , Leo Girardi , Ambra Nanni , Stefano Rubele

First results of simulations are presented which compute the dynamical evolution of a Chandrasekhar-mass white dwarf, consisting of equal amounts of carbon and oxygen, from the onset of violent thermonuclear burning, by means of a new…

Astrophysics · Physics 2009-09-25 M. Reinecke , W. Hillebrandt , J. C. Niemeyer

Convection and turbulence in stellar atmospheres have a significant effect on the emergent flux from late-type stars. The theoretical advancements in convection modelling over recent years have proved challenging for the observers to obtain…

Astrophysics · Physics 2015-06-24 Barry Smalley