Comparison of variations in the visible and ultraviolet spectra of a Centauri.

Abstract

Equivalent-width and central depth measurements of some ultraviolet absorption lines from the spectrum of the He I spectrum variable star a Cen (HD 125823) are presented. The measurements are from 53 short-wavelength and 52 long-wavelength, high-resolution spectrographs taken with the IUE satellite over a 25^d period during 1978 July and August. The IUE observations are consistent with a period of 8^d.8163±0^d.0003 and with a previously unreported period of 9^d.2532±0^d.0003.