相关论文: Direct MD simulation of liquid-solid phase equilib…
We determine the liquid-solid phase diagram for carbon-oxygen and oxygen-selenium plasma mixtures using two-phase MD simulations. We identified liquid, solid, and interface regions using a bond angle metric. To study finite size effects, we…
We develop a method for calculating the equilibrium properties of the liquid-solid phase transition in a classical, ideal, multi-component plasma. Our method is a semi-analytic calculation that relies on extending the accurate fitting…
Sedimentation of the neutron rich isotope $^{22}$Ne may be an important source of gravitational energy during the cooling of white dwarf stars. This depends on the diffusion constant for $^{22}$Ne in strongly coupled plasma mixtures. We…
Quantum corrections can be important for diffusion and the melting temperature of dense plasmas in compact astrophysical objects, particulary white dwarfs and neutron stars. Typically ions in these systems are modeled classically, but…
We investigate phase separation in oxygen-neon (O/Ne) ultramassive white dwarfs (UMWDs). Current stellar evolution codes, such as MESA, only account for $\mathrm{^{16}O/^{20}Ne}$ separation and do not include other minor species. To improve…
Accurate phase diagrams of multicomponent plasmas are required for the modeling of dense stellar plasmas, such as those found in the cores of white dwarf stars and the crusts of neutron stars. Those phase diagrams have been computed using a…
The 3-body crystallization diagrams of C/O/Ne ionic mixtures characteristic of white dwarf interiors are examined within the framework of the density-functional theory of freezing. The crystallization process is described more accurately…
We assess the impact of the trace element ^{22}Ne on the cooling and seismology of a liquid C/O white dwarf (WD). Due to this elements' neutron excess, it sinks towards the interior as the liquid WD cools. The subsequent gravitational…
We study the effects of the sedimentation of the trace element 22Ne in the cooling of white dwarfs. In contrast with previous studies, which adopted a simplified treatment of the effects of 22Ne sedimentation, this is done self-consistently…
We present three-dimensional hydrodynamical simulations of detonations in $1.0 \mathrm{M_{\odot}}$ white dwarfs that have undergone $^{22} \mathrm{Ne}$ distillation during crystallisation. These simulations, conducted with the moving-mesh…
The phase diagram of natural neon has been calculated for temperatures in the range 17-50 K and pressures between 0.01 and 2000 bar. The phase coexistence between solid, liquid, and gas phases has been determined by the calculation of the…
Ultramassive white dwarfs are extreme endpoints of stellar evolution. Recent findings, such as a missing multi-Gyr cooling delay for a number of ultramassive white dwarfs and a white dwarf with a quasi-Chandrasekhar mass, motivate a better…
Phase diagrams of fully ionized binary ionic mixtures are considered within the framework of the linear mixing formalism taking into account recent advances in understanding quantum one-component plasma thermodynamics. We have followed a…
The nuclear reactions that occur in the stellar progenitors of white dwarfs (WDs) lead to an internal composition of 12C, 16O, and a ``contaminant'' nucleus, 22Ne. The 22Ne is produced by helium captures on 14N left from hydrogen burning…
We explore changes in the adiabatic low-order g-mode pulsation periods of 0.526, 0.560, and 0.729 M$_\odot$ carbon-oxygen white dwarf models with helium-dominated envelopes due to the presence, absence, and enhancement of $^{22}$Ne in the…
When white dwarfs freeze the plasma mixtures inside them undergo separation processes which can produce radical changes in the composition profile of the star. The abundance of neutron rich elements, such as $^{22}$Ne or $^{56}$Fe,…
The diffusion coefficients of neutron rich nuclei in crystallizing white dwarf (WD) stars are essential microphysics input for modeling the evolution of the composition profile. Recently, molecular dynamics simulations have been used to…
We study the plasma correlation effects on nonresonant thermonuclear reactions of carbon and oxygen in the interiors of white dwarfs and liquid envelopes of neutron stars. We examine the effects of electron screening on thermodynamic…
A systematic search for multicomponent crystal structures is carried out for five different ternary systems of nuclei in a polarizable background of electrons, representative of accreted neutron star crusts and some white dwarfs. Candidate…
Neutron-star (NS) - white-dwarf (WD) mergers may give rise to observable explosive transients, but have been little explored. We use 2D coupled hydrodynamical-thermonuclear FLASH-code simulations to study the evolution of WD debris-disks…