A review on Asteroseismology

The bright, nearby binary α Centauri provides an excellent laboratory for testing stellar evolution models, as it is one of the few stellar systems for which we have high-precision classical (mass, radius, luminosity) and asteroseismic (p-mode) observations. Stellar models are created and fit to the classical and seismic observations of both stars by allowing for the free variation of convective mixing length parameter α MLT . This system is modeled using five different sets of assumptions about the physics governing the stellar models. There are 31 pairs of tracks (out of ∼150, 000 generated) which fit the classical, binary, and seismic observational constraints of the system within 3 σ. Models with each tested choice of input physics are found to be viable, but the optimal mixing lengths for α Cen A and α Cen B remain the same regardless of the physical prescription. The optimal mixing lengths are α MLT,A /α = 0.932 and α MLT,B /α = 1.095. That α Cen A and α Cen B require sub-and super-solar mixing lengths, respectively, to fit the observations is a trend consistent with recent findings, such as in Kervella et al. (2017), Joyce &Chaboyer (2018), andViani et al. (2018). The optimal models find an age for α Centauri of 5.3 ± 0.3 Gyr.

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“…This can serve as an independent constraint on the evolutionary phase of the star (e.g. Silva Aguirre et al 2013;Di Mauro 2017).…”

Section: Classical and Asteroseismic Observationsmentioning

confidence: 99%

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

Joyce

Chaboyer

2018

ApJ

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“…Uncertainties extend to asteroseismology (17); the calculation of luminosity variation in the search for exoplanets, and cosmological distance measures based on Cepheid variable pulsation-luminosity relations. Based on the higher opacity of iron measured on the Z facility the opacity of iron has been increased by workers modelling variable stars to explain pulsation in O and B-type stars (18,19).…”

Section: Introductionmentioning

confidence: 99%

Radiation burnthrough measurements to infer opacity at conditions close to the solar radiative zone–convective zone boundary

et al. 2023

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Recent measurements at the Sandia National Laboratory of the x-ray transmission of iron plasma have inferred opacities much higher than predicted by theory, which casts doubt on modeling of iron x-ray radiative opacity at conditions close to the solar convective zone-radiative zone boundary. An increased radiative opacity of the solar mixture, in particular iron, is a possible explanation for the disagreement in the position of the solar convection zone-radiative zone boundary as measured by helioseismology and predicted by modeling using the most recent photosphere analysis of the elemental composition. Here, we present data from radiation burnthrough experiments, which do not support a large increase in the opacity of iron at conditions close to the base of the solar convection zone and provide a constraint on the possible values of both the mean opacity and the opacity in the x-ray range of the Sandia experiments. The data agree with opacity values from current state-of-the-art opacity modeling using the CASSANDRA opacity code.

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“…Since the findings of the Z experiments were reported an enhancement in the iron opacity has been invoked by several groups to explain pulsation in O and B-type stars [11,12]. A change in the opacity of iron has implications in asteroseismology [13] and the calculation of luminosity variation in the search for exoplanets.…”

Section: Introductionmentioning

confidence: 99%

A proposal to measure iron opacity at conditions close to the solar convective zone-radiative zone boundary

Hoarty

Morton

Jeffery

et al. 2019

High Energy Density Physics

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A review on Asteroseismology

Cited by 3 publications

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

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

Radiation burnthrough measurements to infer opacity at conditions close to the solar radiative zone–convective zone boundary

A proposal to measure iron opacity at conditions close to the solar convective zone-radiative zone boundary

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