Molecular ions in astrophysics

Preparation and Study of Molecular Structure of Copper Ions Doped in a Silica Xerogel Matrix

The silica xerogel is prepared using copper source; 0.02 mol of Cu(NO3)2.3H2O that has been added to 1 mol TEOS (tetraethyl orthosilicate). The Copper ions are doped to silica matrix by the sol gel method and determination of total molar ratio of components with a reported molar ratio of H2O /TEOS(R) = 6.2. In this method, the acidity the of reaction (pH) depends on the catalyst type in the hyd...

Astrophysics.

Using the oscillation frequencies of α Cen A recently discovered by Bouchy & Carrier (2001, 2002), the available astrometric, photometric and spectroscopic data, we tried to improve the calibration of the visual binary system α Cen. With the revisited masses of Pour-baix et al. (2002) we do not succeed to obtain a solution satisfying all the seismic observational constraints. Relaxing the const...

Generating Process Explanations in Nuclear Astrophysics Generating Explanations in Astrophysics

In this paper we describe ASTRA, a computational aid for generating process explanations in nuclear astrophysics. The system operates in two stages, the rst using knowledge of quantum theory to produce a set of legal reactions among elements and the second searching for pathways of such reactions that explain the evolution of some element in terms of lighter ones. ASTRA has found apparently nov...

Atomic Data for Astrophysics. II. New Analytic FITS for Photoionization Cross Sections of Atoms and Ions

We present a complete set of analytic fits to the non-relativistic photoionization cross sections for the ground states of atoms and ions of elements from H through Si, and S, Ar, Ca, and Fe. Near the ionization thresholds, the fits are based on the Opacity Project theoretical cross sections interpolated and smoothed over resonances. At higher energies, the fits reproduce calculated Hartree-Dir...

Astrophysics.