相关论文: Oscillatory secular modes: The thermal micropulses

Criteria for gravitational collapse of expanding shells in rotating, shearing galaxy disks were determined using three-dimensional numerical simulations in the thin shell approximation. The simulations were run over a grid of 7 independent…

We perform a stability analysis of a tidally excited nonlinear internal gravity wave near the centre of a solar-type star in two-dimensions. The motivation is to understand the tidal interaction between short-period planets and their…

Star formation is intimately linked to the dynamical evolution of molecular clouds. Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass via accretion from the surrounding cloud…

Time-dependent insolation in a planetary atmosphere induces a mass quadrupole upon which the stellar tidal acceleration can exert a force. This "thermal tide" force can give rise to secular torques on the planet and orbit as well as radial…

New non-linear hydrodynamic models have been constructed to simulate the radial pulsations observed in the extreme helium star V652 Her. These use a finer zoning to allow higher radial resolution than in previous simulations. Models…

Evolutionary tracks and pulsational analysis of models with masses of 13-18 $M_\odot$ are presented. We address two important questions. The first one deals with one of the most unresolved problems in astrophysics, i.e., the existence of a…

Rapidly decaying slow magnetoacoustic waves are regularly observed in the solar coronal structures, offering a promising tool for a seismological diagnostics of the coronal plasma, including its thermodynamical properties. The effect of…

We study the modes and stability of non - isothermal coronal loop models with different intensity values of the equilibrium magnetic field. We use an energy principle obtained via non - equilibrium thermodynamic arguments. The principle is…

Prominences show a surprising amount of fine structure and it is widely believed that their threads, as seen in H$\alpha$ observations, provide indirect information concerning magnetic field topology. We investigate the spontaneous…

Studies of non-equilibrium dynamics of cosmological phase transitions may involve a scalar field interacting weakly with the energy-momentum tensor of a thermal plasma. At late times, when the scalar field is approaching equilibrium, it…

Microturbulence, i.e. enhanced fluctuations of plasma density, electric and magnetic fields, is of great interest in astrophysical plasmas, but occurs on spatial scales far too small to resolve by remote sensing, e.g., at ~ 1-100 cm in the…

We derive constraints on the mass-temperature relation of galaxy clusters from their observed luminosity-temperature relation and X-ray temperature function. Adopting the isothermal gas in hydrostatic equilibrium embedded in the universal…

We present here a detailed pulsational study applied to low-mass He-core white dwarfs, based on full evolutionary models representative of these objects. The background stellar models on which our pulsational analysis was carried out were…

We present a linear analysis of acoustic and thermo-reactive instabilities in a diffuse gas, photoionized and heated by a radiation field, cooled by collisional excitation of hydrogen and metal lines. The hydrogen recombination reaction has…

We use a hybrid test particle/N-body simulation to integrate 4 million massless test particle trajectories within a fully self-consistent 10^5 particle N-body simulation. The number of massless particles allows us to resolve fine structure…

We analyse the radial structure of self-gravitating spheres consisting of multiple interpenetrating fluids, such as the X-ray emitting gas and the dark halo of a galaxy cluster. In these dipolytropic models, adiabatic dark matter sits in…

Radiative shock waves show a strong cooling instability at temperatures above approximately 2 times 10^5 K. We numerically investigate this instability by simulating different astronomical objects in which colliding flows play an…

It is shown, in the framework of the Thomas-Fermi model at finite temperature, that a cooling non-degenerate gas of massive neutrinos will, at a certain temperature, become unstable and undergo a first-order phase transition in which…

Radial pulsations of newborn neutron stars (protoneutron stars) are studied for a range of internal temperatures and entropies per baryon predicted by the existing numerical simulations. Protoneutron star models are constructed using a…

For the first time nonradial oscillations of superfluid nonrotating stars are self-consistently studied at finite stellar temperatures. We apply a realistic equation of state and realistic density dependent model of critical temperature of…