Related papers: Free-energy model for fluid helium at high density
When studying high-dimensional dynamical systems such as macromolecules, quantum systems and polymers, a prime concern is the identification of the most probable states and their stationary probabilities or free energies. Often, these…
In this paper, we present a new calculation of composition-dependent radiative cooling and heating curves of low-density gas, intended primarily for use in numerical simulations of galaxy formation and evolution. These curves depend on only…
We present an analytic formulation to model the fluctuating component of the HI signal from the epoch of reionization during the phase of partial heating. During this phase, we assume self-ionized regions, whose size distribution can be…
The properties of hydrogen at high pressure have wide implications in astrophysics and high-pressure physics. Its phase change in the liquid is variously described as a metallization, H2-dissociation, density discontinuity or plasma phase…
The free energy of barium titanate is computed around the Curie temperature as a function of polarization from the first-principles derived effective hamiltonian of Zhong, Vanderbilt and Rabe [Phys. Rev. Lett. 73, 1861 (1994)], through…
Upper limits from the current generation of interferometers targeting the 21-cm signal from high redshifts have recently begun to rule out physically realistic, though still extreme, models of the Epoch of Reionization (EoR). While…
Radiative processes play a pivotal role in shaping the thermal and chemical states of gas across diverse astrophysical environments, from the interstellar medium (ISM) to the intergalactic medium. We present a hybrid cooling model for…
We propose a methodology to perform a self-consistent analysis of the physical properties of the emitting gas of HII galaxies adequate to the data that can be obtained with the XXI century technology. This methodology requires the…
We have studied nonequilibrium dynamics of the one-dimensional Hubbard model using the generalized hydrodynamic theory. We mainly investigated the spatio-temporal profile of charge density, energy density and their currents using the…
We develop a novel finite element method for a phase field model of nematic liquid crystal droplets. The continuous model considers a free energy comprised of three components: the Ericksen's energy for liquid crystals, the Cahn-Hilliard…
Single-phase photoionization equilibrium (PIE) models are often used to infer the underlying physical properties of galaxy halos probed in absorption with ions at different ionization potentials. To incorporate the effects of turbulence, we…
At low densities the standard ionisation history of the intergalactic medium (IGM) predicts a decreasing temperature of the IGM with decreasing density once hydrogen (and helium) reionisation is complete. Heating the high-redshift,…
The thermo-mechanical effect in superfluid helium is used to create an initial chemical potential difference, $\Delta \mu_0$, across a solid $^4$He sample. This $\Delta \mu_0$ causes a flow of helium atoms from one reservoir filled with…
We present a new approach to measure the power-law temperature density relationship $T=T_0 (\rho / \bar{\rho})^{\gamma -1}$ and the UV background photoionization rate $\Gamma_{\rm HI}$ of the IGM based on the Voigt profile decomposition of…
Materials at high pressures and temperatures are of great interest for planetary science and astrophysics, warm dense matter physics, and inertial confinement fusion research. Planetary structure models rely on our understanding of the…
We have calculated the ground state electronic structure of He under pressure from 0 to 1500 GPa using both all-electron full-potential and pseudopotential methods based on the density functional theory (DFT). We find that throughout this…
Accurate phase diagram calculation from molecular dynamics requires systematic treatment and convergence of statistical averages. In this work we propose a Gaussian process regression based framework for reconstructing the free energy…
The relaxation dynamics of superexcited superfluid He nanodroplets is thoroughly investigated by means of extreme-ultraviolet (XUV) femtosecond electron and ion spectroscopy complemented by time-dependent density functional theory (TDDFT).…
Low-frequency axial oscillations (5-50 kHz) stand out as a pervasive feature observed in many types of Hall thrusters. While it is widely recognized that the ionization effects play the central role in this mode, as manifested via the large…
We compute the free energy of helium-4 near the lambda transition based on an exact renormalization-group equation. An approximate solution permits the determination of universal and nonuniversal thermodynamic properties starting from the…