Radiative Opacities

RADIATIVE OPACITIES AND STEllAR PULSATIONS

OP data on CD for mean opacities and radiative accelerations

All monochromatic opacity data from the Opacity Project (OP), together with all codes required for the calculation of mean opacities and radiative accelerations for any required chemical mixture, temperature and mass-density, are being put on a 700 Mb CD which will be made generally available. The present paper gives a concise summary of the contents of the CD. More complete documentation will ...

Radiative forces on lithium: effects of electron recoil and background opacities

Recent results on momentum transfer during photoionization processes determine how the ionizing photon momentum is split between the ejected electron and the recoiling ion. This leads to improved radiative force calculations. The consequences of this recoil for radiative forces are demonstrated by comparing for lithium the new accurate results with calculations based on simpler approximations c...

A numerical strategy for radiative transfer problems with higly oscillating opacities

We propose a numerical method, suitable to study transport problems with highly oscillatory coefficients, based on a formulation of the equations in terms of a semigroup acting on an enlarged phase space. After testing the strategy on a model case, we consider the relevant situation of the radiative transfer equations.

Supernova Neutrino Opacities

In a supernova (SN) core during infall and after collapse, neutrinos are trapped by their interactions with nucleons. For the axial-vector current interactions it is not enough to include static particle-particle correlations. Even the single-nucleon spin autocorrelation reduces the scattering cross section dramatically. Therefore, the dynamical structure of the spin-density structure function ...