Related papers: Statistical relations between stellar spectral and…
The interpretation of stellar apparent fundamental parameters must be treated consistently with the characteristics of their surface rotation law. We develop a model to determine the distribution of the effective temperature and gravity,…
Determining the properties of old stellar populations (those with age >1 Gyr) has long involved the comparison of their integrated light, either in the form of photometry or spectroscopic indexes, with empirical or synthetic templates. Here…
M dwarfs are key targets for high-resolution spectroscopic analyses due to a high incidence of these stars in the solar neighbourhood and their importance as exoplanetary hosts. Several methodological challenges make such analyses…
It is well established that stellar effective temperatures determined from photometry and spectroscopy yield systematically different results. We describe a new, simple method to correct spectroscopically derived temperatures ("excitation…
Properties of galaxies like their absolute magnitude and their stellar mass content are correlated. These correlations are tighter for close pairs of galaxies, which is called galactic conformity. In hierarchical structure formation…
We report on the discovery of a relation between the stellar mass $M^*$ of early-type galaxies (hereafter ETGs), their shape, as parametrized by the Sersic index $n$, and their stellar mass-to-light ratio $M^*/L$. In a 3D log space defined…
We present measurements of fundamental astrophysical properties of nearby, low-mass, K- and M-dwarfs from our DISCOS survey (DIameterS of COol Stars). The principal goal of our study is the determination of linear radii and effective…
We discuss how recent advances in observations, theory and numerical simulations have allowed the stellar community to progress in its understanding of stellar convection, rotation and magnetism and to assess the degree to which the Sun and…
Planets interact with their host stars through gravity, radiation and magnetic fields, and for those giant planets that orbit their stars within ~10 stellar radii (~0.1 AU for a sun-like star), star-planet interactions (SPI) are observable…
In the current era of stellar spectroscopic surveys, synthetic spectral libraries are the basis for the derivation of stellar parameters and chemical abundances. In this paper, we compare the stellar parameters determined using five popular…
Context: Optical interferometry is a powerful tool for observing the intensity structure and angular diameter of stars. When combined with spectroscopy and/or spectrophotometry, interferometry provides a powerful constraint for model…
We calculate directly determined values for effective temperature ($T_{\rm EFF}$) and radius ($R$) for 191 giant stars based upon high resolution angular size measurements from optical interferometry at the Palomar Testbed Interferometer.…
Galaxy clusters provide us with important information about the cosmology of our universe. Observations of the X-ray radiation or of the SZ effect allow us to measure the density and temperature of the hot intergalactic medium between the…
Context. Limb darkening is an important tool for understanding stellar atmospheres, but most observations measuring limb darkening assume various parameterizations that yield no significant information about the structure of stellar…
The stellar initial mass function (IMF) is predicted to depend upon the temperature of gas in star-forming molecular clouds. The introduction of an additional parameter, $T_{IMF}$ , into photometric template fitting, allows galaxies to be…
We present empirical metallicity-dependent calibrations of effective temperature against colours for dwarfs of luminosity classes IV and V and for giants of luminosity classes II and III, based on a collection from the literature of about…
The Euler equation has been accepted as the basic postulate of stellar physics long before the plasma physics was developed. The existence of electrical interaction between particles of interstellar plasma poses the question, how this…
The field of exoplanet research has revitalized interest in M dwarfs, which have become favorite targets of Doppler and transit surveys. Accurate measurements of their basic properties such as masses, radii, and effective temperatures have…
We have developed a method for fast and accurate stellar population parameters determination in order to apply it to high resolution galaxy spectra. The method is based on an optimization technique that combines active learning with an…
We present a new model atmosphere analysis of nine central stars of planetary nebulae. This study is based on a new generation of realistic stellar model atmospheres for hot stars; state-of-the-art, hydrodynamically consistent, spherically…