Related papers: Chemically peculiar stars and their temperature ca…
We present new grids of colors and bolometric corrections for F-K stars having 4000 K < Teff < 6500 K, 0.0 < log g < 4.5 and -3.0 < [Fe/H] < 0.0. A companion paper extends these calculations into the M giant regime. Colors are tabulated for…
We calculate strange star properties, using large N_c approximation with built-in chiral symmetry restoration (CSM). We used a relativistic Hartree Fock mean field approximation method, using a modified Richardson potential with two scale…
Magnetic chemically peculiar (mCP) stars exhibit complex atmospheres that allow the investigation of such diverse phenomena as atomic diffusion, magnetic fields, and stellar rotation. The advent of space-based photometry provides the…
The study of chemically peculiar (CP) stars in open clusters provides valuable information about their evolutionary status. Their detection can be performed using the $\Delta a$ photometric system, which maps a characteristic flux…
Reported are UBV and uvbybeta observations of 15 candidates for Kepler primary astero- seismic targets and 14 other stars in the Kepler field, carried out at the M.G. Fracastoro station of the Catania Astrophysical Observatory. These data…
The ratio of the depths of spectral lines is a powerful indicator of the effective temperature. The method based on this analysis is capable of discerning small temperature variations of individual stars. We apply this spectroscopic data…
We conduct a line-by-line differential analysis of a sample of 125 co-moving pairs of stars (dwarfs and subgiants near solar metallicity). We obtain high precision stellar parameters with average uncertainties in effective temperature,…
Magnetic chemically peculiar (mCP) stars are important to astrophysics because their complex atmospheres lend themselves perfectly to the investigation of the interplay between such diverse phenomena as atomic diffusion, magnetic fields,…
Some selected catalogs of the effective temperatures for F, G and K stars are analyzed. By an improved technique we estimate the external errors of these catalogs from data intercomparisons. The values of the effective temperatures are then…
We present a comprehensive analysis of BRITE photometry for 85 chemically peculiar stars, aimed at refining or determining their rotational periods. Utilizing a uniform Lomb-Scargle-based pipeline, we derived significant periods for 47…
The Delta a photometric system provides an efficient observational method to identify and distinguish magnetic and several other types of chemically peculiar (CP) stars of spectral types B to F from other classes of stars in the same range…
The metallicity dependence of the primary indices of the uvby photometric system for cooler dwarfs (Teff ~ 6500 K to 5000K) is investigated. The data base for the analysis is composed of the overlap between a composite catalog of selected,…
A new method of T_eff determination for CP stars is proposed. The method is based on the fact that the slope of the energy distribution in the Balmer continuum near the Balmer jump is identical for "normal" main sequence stars and for CP…
We present a spectroscopic and photometric calibration to derive effective temperatures $T_{\mathrm{eff}}$ and metallicities [Fe/H] for M dwarfs, based on a Principal Component Analysis of 147 spectral indices measured off moderate…
We pose the question of how much information on the atmospheric parameters of late-type stars can be retrieved purely from colors using standard photometric systems. We carried out numerical experiments using stellar fluxes from model…
In view of the importance of accurate fundamental stellar parameters for `Spectro-photometric dating of stars and galaxies", we present simultaneous effective temperature and metallicity determinations for a sample of 40 stars from…
Eclipsing binary stars are gratifying objects because of their unique geometrical properties upon which all important physical parameters such as masses, radii, temperatures, luminosities and distance may be obtained in absolute scale. This…
A new intrinsic-colour calibration ($(b$--$y)_{o}$--$\beta$) is presented for the $uvby$--$\beta$ photometric system, making use of re-calibrated Hipparcos parallaxes and published reddening maps. This new calibration for…
Context. The chemically peculiar (CP) stars of the upper main sequence are defined by spectral peculiarities that indicate unusual elemental abundance patterns in the presence of diffusion in the calm, stellar atmospheres. Some of them have…
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…