Related papers: Classical Cepheid Pulsation Models. III. The Predi…
Y~Ophiuchi (Y~Oph) is a classical Cepheid reported to be as dim as a Cepheid of about half its pulsation period, and exhibits a low radial velocity and light-curves amplitude. Our objective is to conduct hydrodynamical pulsation modeling of…
In a recent paper it was proposed that for some nonlinear shell models of turbulence one can construct a linear advection model for an auxiliary field such that the scaling exponents of all the structure functions of the linear and…
The reheating process in inflationary universe models is considered as an out-of-equilibrium mixture of two interacting and reacting fluids, and studied within the framework of causal, irreversible thermodynamics. The evolution of the…
Classical Cepheids are key astrophysical laboratories for studying stellar structure and evolution, and for calibrating the cosmic distance scale. Despite major progress, uncertainties remain regarding their masses, luminosities, distances,…
Using linear non-adabatic pulsation analysis, we explore the radial-mode (p-mode) stability of stars across a wide range of mass (0.2 <= M <= 50 Msun), composition (0 <= X <= 0.7, Z=0.001, 0.02), effective temperature (3 000 <= T_eff <= 40…
Single pulses of pulsar radio emission are modeled as superposition of radiation originating from many small subsources that are randomly distributed in the emission region. The individual subsources are given an intrinsic finite angular…
After an overview of general aspects of modelling the pulsation- convection interaction we present reasons why such simulations (in multidimensions) are needed but, at the same time, pose a considerable challenge. We then discuss, for…
Young pulsars deviate from a perfectly regular spin-down by two non-deterministic phenomena: impulsive glitches and timing noise. Both phenomena are interesting per se, and may provide insights into the superfluid properties of neutron…
The complex evolution of turbulent mixing in Rayleigh-Taylor convection is studied in terms of eddy diffusiviy models for the mean temperature profile. It is found that a non-linear model, derived within the general framework of Prandtl…
The $\beta$ Cephei pulsators are massive main-sequence stars, presenting low radial-order modes. These modes probe in particular the chemical gradient at the edge of the convective core. They hence give constraints on macroscopic processes,…
The beamed radio emission from relativistic plasma (particles or bunches), constrained to move along the curved trajectories, occurs in the direction of velocity. We have generalized the coherent curvature radiation model to include the…
The information on stellar parameters and on the stellar interior we can get by studying pulsating stars depends crucially on the available observational constraints: both seismic constraints precision and number of detected modes,…
Structural causal models postulate noisy functional relations among a set of interacting variables. The causal structure underlying each such model is naturally represented by a directed graph whose edges indicate for each variable which…
It is well known that the mere location of a Beat Cepheid model in a Period Ratio \vs Period diagram (Petersen diagram) puts constraints on its metallicity Z. But these bounds are sensitive to the mixture of elements that are lumped into…
The non-resonant secular dynamics of compact planetary systems are modeled by a perturbing function which is usually expanded in eccentricity and absolute inclination with respect to the invariant plane. Here, the expressions are given in a…
I review different types of multi-mode pulsations observed in classical Cepheids and in RR Lyrae-type star. The presentation concentrates on the newest results, with special emphasis on recently detected nonradial oscillations.
Aims. The simulation of three-wave interaction based plasma emission, thought to be the underlying mechanism for Type III solar radio bursts, is a challenging task requiring fully-kinetic, multi-dimensional models. This paper aims to…
In this review, a model (the Random Coupling Model) that gives a statistical description of the coupling of radiation into and out of large enclosures through localized and/or distributed channels is presented. The Random Coupling Model…
This work aims at providing a mathematical and numerical framework for the analysis on the effects of pulsed electric fields on biological media. Biological tissues and cell suspensions are described as having a heteregeneous permittivity…
Standard spectroscopic analyses of variable stars are based on hydrostatic one-dimensional model atmospheres. This quasi-static approach has theoretically not been validated. We aim at investigating the validity of the quasi-static…