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Title: Radial-velocity variations in Alpha Ori, Alpha Sco, and Alpha Her

Abstract

Radial-velocity observations of Alpha Ori, Alpha Sco A, and Alpha Her A are used to study radial-velocity periodicities in M supergiants. The data refer to several metallic lines in the H-alpha region and to H-alpha itself. It is shown that Alpha Ori and Alpha Sco A have cycle lengths of about 1 yr and semiamplitudes of 2 km/s. It is suggested that many semiregular red supergiant varibles such as Alpha Ori may be heading toward chaos. All three stars show short-term stochastic flucutations with an amplitude of 1-2 km/s. It is found that the long-term variability of H-alpha velocities may be a consequence of intermittent failed ejections. 58 refs.

Authors:
; ;  [1]
  1. (National Solar Observatory, Tucson, AZ (USA) Computer Sciences Corp., Seabrook, MD (USA) Iowa State Univ., Ames (USA))
Publication Date:
OSTI Identifier:
6967206
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal; (USA); Journal Volume: 98
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; SUPERGIANT STARS; RADIAL VELOCITY; BALMER LINES; CHARGE-COUPLED DEVICES; CHEMICAL COMPOSITION; EMISSION SPECTRA; LINE WIDTHS; OSCILLATIONS; RED GIANT STARS; ROTATION; GIANT STARS; MOTION; SEMICONDUCTOR DEVICES; SPECTRA; STARS; VELOCITY; 640102* - Astrophysics & Cosmology- Stars & Quasi-Stellar, Radio & X-Ray Sources

Citation Formats

Smith, M.A., Patten, B.M., and Goldberg, L.. Radial-velocity variations in Alpha Ori, Alpha Sco, and Alpha Her. United States: N. p., 1989. Web. doi:10.1086/115293.
Smith, M.A., Patten, B.M., & Goldberg, L.. Radial-velocity variations in Alpha Ori, Alpha Sco, and Alpha Her. United States. doi:10.1086/115293.
Smith, M.A., Patten, B.M., and Goldberg, L.. 1989. "Radial-velocity variations in Alpha Ori, Alpha Sco, and Alpha Her". United States. doi:10.1086/115293.
@article{osti_6967206,
title = {Radial-velocity variations in Alpha Ori, Alpha Sco, and Alpha Her},
author = {Smith, M.A. and Patten, B.M. and Goldberg, L.},
abstractNote = {Radial-velocity observations of Alpha Ori, Alpha Sco A, and Alpha Her A are used to study radial-velocity periodicities in M supergiants. The data refer to several metallic lines in the H-alpha region and to H-alpha itself. It is shown that Alpha Ori and Alpha Sco A have cycle lengths of about 1 yr and semiamplitudes of 2 km/s. It is suggested that many semiregular red supergiant varibles such as Alpha Ori may be heading toward chaos. All three stars show short-term stochastic flucutations with an amplitude of 1-2 km/s. It is found that the long-term variability of H-alpha velocities may be a consequence of intermittent failed ejections. 58 refs.},
doi = {10.1086/115293},
journal = {Astronomical Journal; (USA)},
number = ,
volume = 98,
place = {United States},
year = 1989,
month =
}
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