Discrete Structures in the CS Envelope of the Be star ζ Tau

Abstract

AbstractThe recent cycle of the V/R ratio and RV variations in ζ Tau has been found similar to that reported by Delplace (1970). As a rule, in both cycles, singly-ionized metallic shell lines display discrete components when the descending branch of RV curve of Balmer lines crosses the stellar RV value; a narrow sharp feature is mainly superimposed on a broad and bluer one, both being slowly varying over some months; very weak additional components are suspected on stronger Fe II lines. On another hand, in the ascending branch of RV curve (RV ≥ RVstar), secondary shell components varying in intensity are conspicuous on V and R emissions of the first Balmer lines.