相关论文: The Solar and $\alpha$ Centauri A and B models imp…
The $\alpha$ 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 system's bright magnitude led to a wealth of…
Chromospheres and coronae are common phenomena on solar-type stars. Understanding the energy transfer to these heated atmospheric layers requires direct access to the relevant empirical data. Study of these structures has, by and large,…
The Sun is the most studied of all stars. It is a reference for all other observed stars and a laboratory of fundamental physics helping us understand processes occuring in conditions irreproducible on Earth. However, our understanding of…
The alpha Centauri binary system, owing to its duplicity, proximity and brightness, and its components' likeness to the Sun, is a fundamental calibrating object for the theory of stellar structure and evolution and the determination of…
The precise mechanisms that provide the non-radiative energy for heating the chromosphere and the corona of the Sun and those of other stars constitute an active field of research. By studying stellar chromospheres one aims at identifying…
Alpha Centauri A is the closest solar-type star to the Sun and offers an excellent opportunity to detect the thermal emission of a mature planet heated by its host star. The MIRI coronagraph on JWST can search the 1-3 AU (1"-2") region…
Recent improvements in the modeling of solar convection and line formation led to downward revisions of the solar photospheric abundances of the lighter elements, which in turn led to changes in the radiative opacity of the solar interior…
The Sun is the most studied of all stars, and thus constitutes a benchmark for stellar models. However, our vision of the Sun is still incomplete, as illustrated by the current debate on its chemical composition. The problem reaches far…
Regardless of their close proximity, abundance measurements for both stars in {\alpha} Centauri by different groups have led to varying results. We have chosen to combine the abundance ratios from five similar data sets in order to reduce…
The interior structure of the Sun can be studied with great accuracy using observations of its oscillations, similar to seismology of the Earth. Precise agreement between helioseismological measurements and predictions of theoretical solar…
The small separation (delta nu 01, delta nu 02 and delta nu 13) between the oscillations with low degree l is dependent primarily on the sound speed profile within the stellar core, where nuclear evolution occurs. The detection of such…
Recent revisions of the determination of the solar composition have resulted in solar models in marked disagreement with helioseismic inferences. The effect of the composition change on the model is largely caused by the change in the…
The precise mechanisms that provide the non-radiative energy for heating the chromosphere and the corona of the Sun and other stars are at the focus of intense contemporary research. Observations at submm/mm wavelengths are particularly…
We show that standard solar models are in good agreement with the helioseismologically determined sound speed and density as a function of solar radius, the depth of the convective zone, and the surface helium abundance, as long as those…
$\alpha$ Centauri A is the closest solar-type star to the Sun and offers the best opportunity to find and ultimately to characterize an Earth-sized planet located in its Habitable Zone (HZ). Here we describe initial results from an ALMA…
Hydrodynamical, 3D simulations of the outer layers of the Sun and Alpha Cen A are used to obtain constraints on the properties of turbulent convection in such stars. These constraints enable us to compute - on the base of a theoretical…
Is the Sun likely to have a more opaque interior than previously thought? The solar oxygen (or abundance) problem can be solved with higher interior opacities, reconciling abundance analyses based on 3D convective atmospheres with the…
The Sun is the most constrained and well-studied of all stars. As a consequence, the physical ingredients entering solar models are used as a reference to study all other stars observed in the Universe. However, our understanding of the…
The bright, nearby binary $\alpha$ 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…
The Alpha Centauri AB system is an attractive one for radial velocity observations to detect potential exoplanets. The high metallicity of both Alpha Centauri A and B suggest that they could have possessed circumstellar discs capable of…