Asteroseismology of $\mathsf{\alpha}$ Centauri A - Evidence of rotational splitting

  title={Asteroseismology of \$\mathsf\{\alpha\}\$ Centauri A - Evidence of rotational splitting},
  author={Mich{\"a}el Bazot and François Bouchy and Hans Kjeldsen and St{\'e}phane Charpinet and M. Laymand and Sylvie Vauclair},
  journal={Astronomy and Astrophysics},
Context. Asteroseismology provides a unique tool for studying stellar interiors. Recently p modes have been detected on the bright solar-like star α  Cen A thanks to high-precision radial-velocity measurements. However, a better characterisation of these p modes is clearly needed to constrain theoretical models. Aims. We observed α  Cen A during five nights using the HARPS spectrograph in order to improve our knowledge of the seismic properties of this star. Methods. We performed high-precision… 

Figures and Tables from this paper

Reinvestigating α Centauri AB in light of asteroseismic forward and inverse methods

Context. The α Cen stellar system is the closest neighbour to our Sun. Its main component is a binary composed of two main-sequence stars, one more massive than the Sun and one less massive. The

On the uncertain nature of the core of α Cen A

High-quality astrometric, spectroscopic, interferometric and, importantly, asteroseismic observations are available for $\alpha$ Cen A, which is the closest binary star system to earth. Taking all

Classically and Asteroseismically Constrained 1D Stellar Evolution Models of α Centauri A and B Using Empirical Mixing Length Calibrations

The bright, nearby binary α Centauri provides an excellent laboratory for testing stellar evolution models, because it is one of the few stellar systems for which we have high-precision classical

Mode lifetimes of stellar oscillations - Implications for asteroseismology

Context. Successful inference from asteroseismology relies on at least two factors: that the oscillations in the stars have amplitudes large enough to be clearly observable, and that the oscillations

On the Nature of the Core of α Centauri A: The Impact of the Metallicity Mixture

Forward asteroseismic modelling plays an important role towards a complete understanding of the physics taking place in deep stellar interiors. With a dynamical mass in the range over which models

Uncertainties and biases in modelling 16 Cygni A and B

  • M. Bazot
  • Geology
    Astronomy & Astrophysics
  • 2020
Aims. In this study I assess how existing data for the solar analogues 16 Cyg A and B, in particular the asteroseismic measurements obtained from Kepler, constrain theoretical stellar models. The

The Current Status of Asteroseismology

Stellar evolution, a fundamental bedrock of modern astrophysics, is driven by the physical processes in stellar interiors. While we understand these processes in general terms, we lack some important

The Solar-Stellar Connection: Magneto-Acoustic Pulsations in 1.5M⊙ – 2M⊙ Peculiar A Stars

Stellar astronomers look on in envy at the wealth of data, the incredible spatial resolution, and the maturity of the theoretical understanding of the Sun. Yet the Sun is but one star, so stellar

Kepler observations of the asteroseismic binary HD 176465

Binary star systems are important for understanding stellar structure and evolution, and are especially useful when oscillations can be detected and analysed with asteroseismology. However, only four

Modeling and use of stellar oscillation visibilities

  • J. Schou
  • Physics
    Astronomy & Astrophysics
  • 2018
Context. Recently our ability to study stars using asteroseismic techniques has increased dramatically, largely through the use of space based photometric observations. Work has also been performed



Analysis of $\alpha$ Centauri AB including seismic constraints

Detailed models of α  Cen A and B based on new seismological data for α  Cen B by Carrier & Bourban ([CITE]) have been computed using the Geneva evolution code including atomic diffusion. Taking into

Asteroseismology of the planet-hosting star μ Arae I. The acoustic spectrum

We present HARPS spectroscopy of μ Arae (HD 160691) performed for studying the origin of the metallicity excess in this planet-hosting stars. The asteroseismologic campaign led to the previously

Constraining fundamental stellar parameters using seismology. Application to α Centauri AB

We apply the Levenberg-Marquardt minimization algorithm to seismic and classical observables of theαCen binary system in order to derive the fundamental parameters ofαCenA+B, and to analyze the

Solar-like Oscillations in α Centauri B

We have made velocity observations of the star α Centauri B from two sites, allowing us to identify 37 oscillation modes with l = 0-3. Fitting to these modes gives the large and small frequency

Rotation, turbulence and evidence for magnetic fields in southern dwarfs

We model high-resolution spectra using a simple radiative transfer analysis to derive projected rotational velocities (v sin i) and macroturbulent velocity dispersions (vmac) for 49 southern dwarf

The diameters of $\alpha$ Centauri A and B - A comparison of the asteroseismic and VINCI/VLTI views

We compare the first direct angular diameter measurements obtained on our closest stellar neighbour, Centauri, to recent model diameters constrained by asteroseismic observations. Using the VINCI

Ultra-High-Precision Velocity Measurements of Oscillations in α Centauri A

We have made differential radial velocity measurements of the star α Centauri A using two spectrographs, the UV-Visual Echelle Spectrograph (UVES) and the University College London Echelle

Constraining the difference in convective blueshift between the components of alpha Centauri with precise radial velocities

New radial velocities of Cen A & B obtained in the framework the Anglo-Australian Planet Search programme as well as in the CORALIE programme are added to those by Endl et al. (2001) to improve the

Solar p-mode linewidths from recent BiSON* helioseismological data

We present low-degree solar p-mode linewidths from the analysis of several high-resolution frequency spectra generated from high-quality Doppler velocity data collected - in integrated sunlight - by

A new seismic analysis of Alpha Centauri

Models of α Cen A &Bh avebeen computed using the masses determined by Pourbaix et al. (2002) and the data derived from the spectroscopic analysis of Neuforge & Magain (1997). The seismological data