Related papers: The effect of activity on stellar temperatures and…
Numerous investigations on the fundamental properties of low-mass stars using eclipsing binaries indicate a strong discrepancy between theory and observations that is still awaiting explanation. Current models seem to predict radii for…
In recent years, analyses of eclipsing binary systems have unveiled differences between the observed fundamental properties of low-mass stars and those predicted by stellar structure models. Particularly, radius and effective temperatures…
The recent burst in the number of radii measurements of very low-mass stars from eclipsing binaries and interferometry of single stars has opened more questions about what can be causing the discrepancy between the observed radii and the…
Evidence from the analysis of eclipsing binary systems revealed that late-type stars are larger and cooler than predicted by models, and that this is probably caused by stellar magnetic activity. In this work, we revisit this problem taking…
We present empirical relations for determining the amount by which the effective temperatures and radii---and therefore the estimated masses---of low-mass stars and brown dwarfs are altered due to chromospheric activity. Accurate estimates…
A long-standing issue in the theory of low mass stars is the discrepancy between predicted and observed radii and effective temperatures. In spite of the increasing availability of very precise radius determinations from eclipsing binaries…
We present empirical relations for determining the amount by which the effective temperatures and radii -- and therefore the estimated masses -- of low-mass stars and brown dwarfs are altered due to chromospheric activity. We base our…
In this paper we present and analyse determinations of effective temperatures of planet-hosting stars using infrared (IR) photometry. One of our goals is the comparison with spectroscopic temperatures to evaluate the presence of systematic…
Eclipsing binaries with M-type components are still rare objects. Strong observational biases have made that today only a few eclipsing binaries with component masses below 0.6 Msun and well-determined fundamental properties are known.…
The activity levels of stars are influenced by several stellar properties, such as stellar rotation, spectral type and the presence of stellar companions. In analogy to binaries, planetary companions are also thought to be able to cause…
Stellar fundamental properties (masses, radii, effective temperatures) can be extracted from observations of eclipsing binary systems with remarkable precision, often better than 2%. Such precise measurements afford us the opportunity to…
This paper proposes the idea that the observed dependence of stellar activity cycles on rotation rate can be a manifestation of a stronger dependence on the effective temperature. Observational evidence is recalled and theoretical arguments…
Magnetic fields and mass accretion processes create dark and bright spots on the surface of young stars. These spots manifest as surface thermal inhomogeneities, which alter the global temperature measured on the stars. To understand the…
Magnetic fields and stellar spots can alter the equivalent widths of absorption lines in stellar spectra, varying during the activity cycle. This also influences the information that we derive through spectroscopic analysis. In this study…
Empirical correlations between stellar parameters such as rotation or radius and magnetic activity diagnostics require estimates of the effective temperatures and the stellar radii. The aim of this study is to propose simple methods that…
Eclipsing binary stars provide highly accurate measurements of the fundamental physical properties of stars. They therefore serve as stringent tests of the predictions of evolutionary models upon which most stellar age determinations are…
We have executed a survey of nearby, main sequence A, F, and G-type stars with the CHARA Array, successfully measuring the angular diameters of fortyfour stars with an average precision of ~ 1.5%. We present new measures of the bolometric…
Frequency separations used to infer global properties of stars through asteroseismology can change depending on the strength and at what epoch of the stellar cycle the p-mode frequencies are measured. In the Sun these variations have been…
Accurate determinations of masses and radii in binary stars, along with estimates of the effective temperatures, metallicities, and other properties, have long been used to test models of stellar evolution. As might be expected,…
We report the determination from high-resolution spectra of the atmospheric parameters and abundances of 13 chemical species (among which lithium) in 8 single-lined active binaries. These data are combined with our previous results for 6…