Related papers: Model-independent determination of sharp features …
Asteroseismology of solar-type stars is an important tool for constraining stellar parameters and internal structure. Several frequency combinations are largely used for comparisons between models and observations. In particular, the…
In recent years there has been some progress towards detecting solar-like oscillations in stars. The goal of this challenging project is to analyse frequency spectra similar to that observed for the Sun in integrated light. In this context…
The oscillation spectra of solar-type stars may in the not-too- distant future be used to constrain certain properties of the stars. The CD diagram of large versus small frequency separations is one of the powerful tools available to infer…
Convection in stars excites resonant acoustic waves which depend on the sound speed inside the star, which in turn depends on properties of the stellar interior. Therefore, asteroseismology is an unrivaled method to probe the internal…
The large frequency separation between modes of the same degree and consecutive orders in a star is approximately proportional to the square root of its mean density. To determine the large frequency separation as accurately as possible a…
Solar-like oscillations are expected to be excited in stars of up to about 1.6 solar masses. Most of these stars will have convective cores during their Main-sequence evolution. At the edges of these convective cores there is a rapid…
Stars with spectral types earlier than about F0 on (or close) to the main sequence have long been believed to lack observable surface convection, although evolutionary models of A-type stars do predict very thin surface convective zones. We…
Using the CoRoT space based photometry of the O-type binary HD46149, stellar atmospheric effects related to rotation can be separated from pulsations, because they leave distinct signatures in the light curve. This offers the possibility of…
The CoRoT short asteroseismic runs give us the opportunity to observe a large variety of late-type stars through their solar-like oscillations. We report the observation and modeling of the F5V star HD 175272. Our aim is to define a method…
Recently, the study of the CoRoT target HD 49933 showed evidence of variability of its magnetic activity. This was the first time that a stellar activity was detected using asteroseismic data. For the Sun and HD 49933, we observe an…
In the present paper, we aim to constrain the properties of the ionisation region in a star from the oscillation frequency variation (a so-called glitch) caused by rapid structural variations in this very region. In particular, we seek to…
We present the first detections by the NASA K2 Mission of oscillations in solar-type stars, using short-cadence data collected during K2 Campaign\,1 (C1). We understand the asteroseismic detection thresholds for C1-like levels of…
It is well known that in the Sun, the frequencies and amplitudes of acoustic modes vary throughout the solar cycle. Indeed, while the magnetic activity goes towards its maximum, the frequencies of the modes increase and their amplitudes…
The CoRoT satellite has provided high-quality light curves of several solar-like stars. Analysis of the light curves provides oscillation frequencies that make it possible to probe the interior of the stars. However, additional constraints…
The goal of stellar evolution theory is to predict the structure of stars throughout their lifetimes. Usually, these predictions can be assessed only indirectly, for example by comparing predicted and observed effective temperatures and…
We investigate the influence of the ionization of helium on the low-degree acoustic oscillation frequencies in model solar-type stars. The signature in the oscillation frequencies characterizing the ionization-induced depression of the…
Our knowledge of the dynamics of stars has undergone a revolution thanks to the simultaneous large amount of high-quality photometric observations collected by space-based asteroseismology and ground-based high-precision spectropolarimetry.…
The determination of the size of the convective core of main-sequence stars is usually dependent on the construction of models of stars. Here we introduce a method to estimate the radius of the convective core of main-sequence stars with…
p-mode oscillations in solar-like stars are excited by the outer convection zone in these stars and reflected close to the surface. The p-modes are trapped inside an acoustic cavity, but the modes only stay trapped up to a given frequency…
We present the asteroseismic study of the early red-giant star KIC 4448777, complementing and integrating a previous work (Di Mauro et al. 2016), aimed at characterizing the dynamics of its interior by analyzing the overall set of data…