Pulsational mode-typing in line profile variables. V - Multimodes and 'moving shells' in Nu Eridani and other Beta Cephei stars

Abstract

view Abstract Citations (25) References (34) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Pulsational mode typing in line profile variables. V. Multimodes and "moving shells" in nu Eridani and other beta Cephei stars. Smith, M. A. Abstract An analysis of 31 high-resolution Reticon observations of the Si III 4567 A line reveals that most of its variations in shape are a result of nonlinear hydrodynamic processes that remain in phase with the dominant fourth (radial velocity-producing) mode. Line profile analysis shows that this fourth mode is compatible only with radial pulsation and incompatible with any nonradial pulsation mode, including any with m = 0. When the hydrodynamical effects are nearly absent from the profiles at certain times during the cycle, only one of the three nonradial modes (-m = l) is found to be of importance in describing the residual profile variations; this is in agreement with the star's presumed equator-on aspect and with energy equipartition for the triplet-modes. Several conditions imposed by the spectroscopic and photometric amplitudes of the triplet modes require the identification l = 2, and m = -2, -1, and 0. Publication: The Astrophysical Journal Pub Date: February 1983 DOI: 10.1086/160679 Bibcode: 1983ApJ...265..338S Keywords: Cepheid Variables; Line Spectra; Stellar Oscillations; Stellar Spectra; Radial Velocity; Shock Waves; Signal To Noise Ratios; Stellar Atmospheres; Astrophysics full text sources ADS | data products SIMBAD (7) Related Materials (6) Part 1: 1980ApJ...238..250C Part 2: 1980ApJ...238..667C Part 3: 1980ApJ...240..149S Part 4: 1982ApJ...254..242S Part 6: 1985ApJ...288..266S Part 7: 1986ApJ...304..728S