High time-resolution spectroscopy of the Beta Cephei variable BW Vulpeculae using a CCD

Abstract

view Abstract Citations (27) References (21) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS High time-resolution spectroscopy of the beta Cephei variable BW Vulpeculae using a CCD. Young, A. ; Furenlid, I. ; Snowden, M. S. Abstract A high-time-resolution study is reported of line profile and photometric variations in the spectrum of the extreme Beta Cephei variable BW Vulpeculae. Spectroscopic observations of the H-alpha 6563-A and C II 6578- and 6582-A lines were performed with the 2.1-m coude spectrograph at Kitt Peak National Observatory using an experimental Fairchild CCD-211 as the detector, with photometry performed simultaneously in the y filter of the ubvy system with the 40-cm telescope at Mount Laguna Observatory, at a time resolution of approximately 13 minutes throughout one entire stellar cycle. Significant variations in the heliocentric radial velocities, equivalent widths and line profiles of the three lines are observed, together with a stillstand in the light curves which is identified with a discontinuity in the velocity curve. The observed variations are interpreted in terms of a destabilizing mechanism for driving pulsations in the outer atmosphere based on the pressure dependence of the helium ionization equilibrium. Publication: The Astrophysical Journal Pub Date: May 1981 DOI: 10.1086/158877 Bibcode: 1981ApJ...245..998Y Keywords: Charge Coupled Devices; Line Spectra; Stellar Spectra; Stellar Spectrophotometry; Variable Stars; Calcium; Carbon; Gas Ionization; H Alpha Line; Helium; Hertzsprung-Russell Diagram; Light Curve; Radial Velocity; Radiative Transfer; Spectral Line Width; Stellar Atmospheres; Astronomy full text sources ADS | data products SIMBAD (1)