The two hybrid B-type pulsators: ν Eridani and 12 Lacertae

  title={The two hybrid B-type pulsators: $\nu$ Eridani and 12 Lacertae},
  author={W. Dziembowski and A. Pamyatnykh},
  journal={Monthly Notices of the Royal Astronomical Society},
The rich oscillation spectra determined for the two stars, ν Eridani and 12 Lacertae, present an interesting challenge to stellar modelling. The stars are hybrid objects showing not only a number of modes at frequencies typical for β Cep stars but also one mode at frequency typical for SPB stars. We construct seismic models of these stars considering uncertainties in opacity and element distribution. We also present estimate of the interior rotation rate and address the matter of mode… Expand

Figures and Tables from this paper

Pulsating B-type Stars in the Open Cluster NGC 884: Frequencies, Mode Identification, and Asteroseismology
Recent progress in the seismic interpretation of field β Cep stars has resulted in improvements of the physical description in the stellar structure and evolution model computations of massive stars.Expand
A method for the asteroseismic analysis of β Cephei stars is presented and applied to the star ν Eridani. The method is based on the analysis of rotational splittings and their asymmetries usingExpand
The β Cep/SPB star 12 Lacertae: extended mode identification and complex seismic modelling
Results of mode identification and seismic modelling of the β Cep/SBP star 12 Lacertae are presented. Using data on the multi-colour photometry and radial velocity variations, we determine orExpand
Testing the effects of opacity and the chemical mixture on the excitation of pulsations in B stars
The B-type pulsators known asβ Cephei and Slowly Pulsating B (SPB) stars present pulsations driven by theκ mechanism, which operates thanks to an opacity bump due to the iron group elements. InExpand
New Beta Cephei Stars from the KELT Project
We present the results of a search for Galactic β Cephei stars, which are massive pulsating stars with both pressure modes and mixed modes. Thus, these stars can serve as benchmarks for seismologicalExpand
Constraints on opacities from complex asteroseismology of B-type pulsators: the β Cephei star θ Ophiuchi
We present results of a comprehensive asteroseismic modelling of the β Cephei variable θ Ophiuchi. We call these studies complex asteroseismology because our goal is to reproduce both pulsationalExpand
Opacity Effects on Pulsations of A-Type Stars
The effects of opacities in driving pulsations and extending the pulsation instability region for B-type stars (SPB and $\beta$ Cep variables) have recently been explored by, e.g., Walczak et al.Expand
Opacity Effects on Pulsations of Main-Sequence A-Type Stars.
Opacity enhancements for stellar interior conditions have been explored to explain observed pulsation frequencies and to extend the pulsation instability region for B-type main-sequence variableExpand
Interpretation of the BRITE oscillation data of the hybrid pulsator ν Eridani: a call for the modification of stellar opacities
The analysis of the BRITE oscillation spectrum of the main sequence early B-type star $\nu$ Eridani is presented. Only models with the modified mean opacity profile can account for the observedExpand
The impact of enhanced iron opacity on massive star pulsations: updated instability strips
Recently, Bailey et al. (2015) made a direct measurement of the Iron opacity at the physical conditions of the solar tachocline. They found that the wavelength-integrated Iron opacity is roughly 75%Expand


Asteroseismology of the β Cephei star ν Eridani: massive exploration of standard and non-standard stellar models to fit the oscillation data
We present the results of a detailed seismic modelling of the Cephei star Eridani with the Li‘ ege evolution and pulsation codes. We selected four clearly detected, well-identified and independentExpand
Asteroseismology of the β Cephei star ν Eridani: interpretation and applications of the oscillation spectrum
The oscillation spectrum of v Eri is the richest known for any variable of the β Cephei type. We interpret the spectrum in terms of normal mode excitation and construct seismic models of the star.Expand
Abundance analysis of prime B-type targets for asteroseismology. I. Nitrogen excess in slowly-rotating beta Cephei stars
Seismic modelling of the beta Cephei stars promises major advances in our understanding of the physics of early B-type stars on (or close to) the main sequence. However, a precise knowledge of theirExpand
The Potential of Asteroseismology for Hot, Subdwarf B Stars: A New Class of Pulsating Stars?
We present key sample results of a systematic survey of the pulsation properties of models of hot B subdwarfs. We use equilibrium structures taken from detailed evolutionary sequences of solarExpand
Asteroseismology of the β Cephei star 12 (DD) Lacertae : photometric observations, pulsational frequency analysis and mode identification
We report a multisite photometric campaign for the beta Cephei star 12 Lacertae. 750 h of high-quality differential photoelectric Str�mgren, Johnson and Geneva time-series photometry were obtainedExpand
β Cephei stars in the ASAS-3 data. II. 103 new β Cephei stars and a discussion of low-frequency modes
Context. The β  Cephei stars have been studied for over a hundred years. Despite this, many interesting problems related to this class of variable stars remain unsolved. Fortunately, these stars seemExpand
Asteroseismology of the β Cephei star ν Eridani – IV. The 2003–2004 multisite photometric campaign and the combined 2002–2004 data
We report on the second multisite photometric campaign devoted to ν Eridani (ν Eri). The campaign, carried out from 2003 September 11 to 2004 February 16, was very nearly a replica of the firstExpand
Long term photometric monitoring with the Mercator telescope. Frequencies and mode identification of
Aims. We selected a large sample of O-B stars that were considered as (candidate) slowly pulsating B, beta Cep, and Maia stars after the analysis of their hipparcos data. We analysed our new sevenExpand
Rotational Velocities of B Stars
We measured projected rotational velocities for nearly 1100 B stars with these results. (1) They average substantially less than those published in the Bright Star Catalogue and are about one-quarterExpand
Photometric amplitudes and phases of nonradial oscillation in rotating stars
Effects of rotational mode coupling on photometric parameters of stellar oscillations are studied. At moderate rotation rates, a strong coupling between modes of spherical harmonic degree, $\ell$,Expand