Theoretical p Mode Oscillation Frequencies for the Rapidly Rotating Delta Scuti Star Alpha Ophiuchi

Abstract

A rotating, two dimensional stellar model is evolved to match the approximate conditions of Alpha Oph. Both axisymmetric and nonaxisymmetric oscillation frequencies are computed for 2D rotating models which approximate the properties of Alpha Oph. These computed frequencies are compared to the observed frequencies. Oscillation calculations are made assuming the eigenfunction can be fit with six Legendre polynomials, but comparison calculations with eight Legendre polynomials show the frequencies agree to within about 0.26% on average. The surface horizontal shape of the eigenfunctions for the two sets of assumed number of Legendre polynomials agrees less well, but all calculations show significant departures from that of a single Legendre polynomial. It is still possible to determine the large separation, although the small separation is more complicated to estimate. With the addition of the nonaxisymmetric modes with |m| less than or equal 4, the frequency space becomes sufficiently dense that it is difficult to comment on the adequacy of the fit of the computed to the observed frequencies. While the nonaxisymmetric frequency mode splitting is no longer uniform, the frequency difference between the frequencies for positive and negative values of the same m remains 2m times the rotation rate.

ApJ accepted

References in corpus (12)

• Effects of gravitational darkening on the determination of fundamental parameters in fast rotating B-type stars
• Acoustic oscillations of rapidly rotating polytropic stars. II. Effects of the Coriolis and centrifugal accelerations
• Asteroseismology and Interferometry
• Acoustic oscillations in rapidly rotating polytropic stars I. Effects of the centrifugal distortion
• Imaging and Modeling Rapidly Rotating Stars: Alpha Cephei and Alpha Ophiuchi
• Regular patterns in the acoustic spectrum of rapidly rotating stars
• On the Determination of the Rotational Oblateness of Achernar
• Radial and Nonradial Oscillation Modes in Rapidly Rotating Stars
• Rotationally-modulated g-modes in the rapidly-rotating delta Scuti star Rasalhague (alpha Ophiuchi)
• On the interpretation of echelle diagrams for solar-like oscillations. Effect of centrifugal distortion
• Structure of Uniformly Rotating Stars
• Rotational Splitting of Pulsational Modes

Cited by in corpus (8)

• KIC 4142768: An Evolved Gamma Doradus/Delta Scuti Hybrid Pulsating Eclipsing Binary with Tidally Excited Oscillations
• Pulsation analysis and its impact on primary transit modeling in WASP-33
• Kepler Eclipsing Binaries with $\delta$ Scuti/$\gamma$ Doradus Pulsating Components 1: KIC 9851944
• Revisiting the pulsational characteristics of the exoplanet host star $\beta$ Pictoris
• Unexpected series of regular frequency spacing of delta Scuti stars in the non-asymptotic regime -- I. The methodology
• Oscillations of 2D ESTER models. I. The adiabatic case
• Matching the Spectral Energy Distribution and p Mode Oscillation Frequencies of the Rapidly Rotating Delta Scuti Star ? Ophiuchi with a 2D Rotating Stellar Model
• Scaling of oscillation frequencies in rotating stars