1 Introduction

Calcium lines are present in solar (see e.g. Moore et al. 1966; Holweger 1972; Grevesse 1984) and stellar spectra (see e.g. Merrill 1956; Adelman & Davis Philip 1992). Adelman & Davis Philip (1992) have found, for example, neutral calcium lines in the Gamma Geminorum spectrum and Trimble (1991) reports the presence of this product of alpha processes in SN 1987 A ejecta. Consequently, Stark broadening data of neutral calcium spectral lines are of interest for stellar plasma as well as for laboratory plasma research and modeling. Neutral calcium spectral lines broadened by Stark effect have been investigated experimentally (Kusch & Pritschow 1970; Hühn & Kusch 1973) and theoretically (Griem 1974; Marassinghe & Lovett 1986). Stark-effect interaction constants for seven solar calcium lines, whose abundances are sensitive to Stark broadening, have been estimated by Holweger (1972).

In accordance with our project (see e.g. Dimitrijevic 1996a) to make available to astrophysicists and physicists an as large as possible set of reliable semiclassical Stark broadening data needed for the investigation, diagnostics and modeling of various plasmas in astrophysics, physics and technology, we have calculated within the semiclassical-perturbation formalism (Sahal-Bréchot 1969a,b see also Sahal-Bréchot 1974; Dimitrijevic & Sahal-Bréchot 1984) electron-, proton-, ionized helium-, ionized magnesium-, ionized silicon-, and ionized iron-impact line widths and shifts for 189 neutral calcium multiplets. Consequently, the relevant data for all principal perturbers in the solar plasma are provided.