Atomic data for opacity calculations. I. General description

Abstract

Extensive calculations of accurate data are being made in a collaborative effort referred to as the Opacity Project. These data will be used to obtain improved values for opacities in stellar envelopes, and should also be of interest for other problems in physics and astronomy. The present paper, which is the first in a series, gives some of the formulae from thermodynamics and atomic physics which are required for opacity calculations.