Related papers: Model-independent determination of sharp features …
Context. The large quantity of high-quality asteroseismic data that obtained from space-based photometric missions and the accuracy of the resulting frequencies motivate a careful consideration of the accuracy of computed oscillation…
The solar-cyle variation of acoustic mode frequencies has a frequency dependence related to the inverse mode inertia. The discrepancy between model predictions and measured oscillation frequencies for solar and solar-type stellar acoustic…
Convection in stars excites resonant acoustic waves. The frequencies of these oscillations depend on the sound speed inside the star, which in turn depends on density, temperature, gas motion, and other properties of the stellar interior.…
The richness and very high accuracy of the observed frequencies of solar oscillations provide tight constraints on the structure of the solar interior and hence on the assumptions underlying the calculation of solar models. This permits the…
Context. In asteroseismology the pulsation mode frequencies of a star are the fundamental data that are compared to theoretical predictions to determine a star's interior physics. Recent significant advances in the numerical, theoretical…
We study the frequency dependence of the frequency shifts of the low-degree p modes measured in the F5V star HD 49933, by analyzing the second run of observations collected by the CoRoT satellite. The 137-day light curve is divided into two…
For more than ten years, solar-like oscillations have been detected and frequencies measured for a growing number of stars with various characteristics (e.g. different evolutionary stages, effective temperatures, gravities, metal abundances…
Recently, the study of the CoRoT target, HD49933, 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 HD49933, we observe an…
Bowman et al. (2019) reported low-frequency photometric variability in 164 O- and B-type stars observed with K2 and TESS. They interpret these motions as internal gravity waves, which could be excited stochastically by convection in the…
The oscillations of the solar-like star HD 49933 have been observed thoroughly by CoRot. Two dozens of frequency shifts, which are closely related with the change in magnetic activity, have been measured. To explore the effects of the…
In helioseismology, there is a well-known offset between observed and computed oscillation frequencies. This offset is known to arise from improper modeling of the near-surface layers of the Sun, and a similar effect must occur for models…
We present a detailed study of the small frequency separations as diagnostics of the mass of the convective core and evolutionary stage of solar-type stars. We demonstrate how the small separations can be combined to provide sensitive tests…
Recent photometric observations of massive stars have identified a low-frequency power excess which appears as stochastic low-frequency variability in light curve observations. We present the oscillation properties of high resolution…
Oscillations detected on the solar surface provide a unique possibility for investigations of the interior properties of a star. Through major observational efforts, including extensive observations from space, as well as development of…
We present a new method for determining the location of active bands of latitude on solar-type stars, which uses stellar-cycle-induced frequency shifts of detectable solar-like oscillations. When near-surface activity is distributed in a…
People can diagnose the interiors of stars by sensing their pulsations. Pulsation modes, which are determined by the internal state and structure of a star, are typically considered stable over short timescales. These independent pulsation…
The space-borne missions CoRoT and Kepler opened up a new opportunity for better understanding stellar evolution by probing stellar interiors with unrivalled high-precision photometric data. Kepler has observed stellar oscillation for four…
We present a study of multi-wavelength observations, of a C 2.3 solar flare in Active Region NOAA 12353, observed on 2015 May 23, which reveal new properties of acoustic waves in the flaring region. The space-, and ground-based data…
Solar-like oscillations are stochastically excited by turbulent convection at the surface layers of the stars. We study the role of the surface metal abundance on the efficiency of the stochastic driving in the case of the CoRoT target HD…
High-precision frequencies of acoustic modes in red giant stars are now available thanks to the long observing length and high-quality of the light curves provided by the NASA Kepler mission, thus allowing to probe the interior of evolved…