Related papers: Physical Parameters for RR Lyrae Stars in the SDSS…

Based on high resolution and high signal-to-noise ratio (S/N) spectra analysis of 90 solar type stars, we have established several new metallicity calibrations in Teff range [5600, 6500] K based on red spectra with the wavelength range of…

With the aid of the All Sky Automated Survey (ASAS) database on the Galactic field, we compare the iron abundances of fundamental mode RR Lyrae stars derived from the Fourier parameters with those obtained from low-dispersion spectroscopy.…

We present the results of a deep, wide-area variability survey in the Southern hemisphere, the first of its kind. As part of the Catalina Sky Surveys, the Siding Spring Survey (SSS) has covered $14,800$ square degrees in the declination…

We present new estimates of the basic stellar parameters of the non-eruptive, eclipsing symbiotic system, RW Hydrae. A set of photometric and spectroscopic data was used to model this object simultaneously from the light and radial velocity…

The optical UBVRI photometric analysis has been established using SLOAN DIGITAL SKY SURVEY (SDSS database) in order to estimate the astrophysical parameters of poorly studied open star cluster IC 2156. The results of the present study are…

We derive new empirical calibrations for strong-line diagnostics of gas phase metallicity in local star forming galaxies by uniformly applying the Te method over the full metallicity range probed by the Sloan Digital Sky Survey (SDSS). To…

RR Lyrae stars (RRLs) are old pulsating variables widely used as metallicity tracers due to the correlation between their metal abundances and light curve morphology. With ESA Gaia DR3 providing light curves for about 270,000 RRLs, there is…

The kinematical parameters of the local field RR Lyrae population and the zero point of the log P--<M_K> relation for these variables are inferred by applying the statistical parallax (maximum-likelihood) technique to a sample of 182 RR…

The evolution of stellar disks is of great importance for understanding many aspects of galaxy formation. In this work we perform stellar population synthesis on radially resolved photometry of 564 disk galaxies from the SDSS DR5, selected…

We present a machine learning method to assign stellar parameters (temperature, surface gravity, metallicity) to the photometric data of large photometric surveys such as SDSS and SKYMAPPER. The method makes use of our previous effort in…

We use photometry from the recent AllWISE Data Release of the Wide-field In-frared Survey Explorer (WISE) of 129 calibration stars, combined with prior distances obtained from the established $M_V-$[Fe/H] relation and Hubble Space Telescope…

The space photometric project "Lyra" is developed now in Russia.The project purpose is determination of the photometric information and coordinates of the natural and artificial space objects, from the brightest ones to 16^m in visual…

Classical double-mode pulsators (RR Lyrae stars and delta Cepheids) are important for their simultaneous pulsation in low-order radial modes. This enables us to put stringent constraints on their physical parameters. We use 30 bright…

In this paper, we use cubic polynomials to approximate RR Lyrae light curves and apply the method to HST data of RR Lyraes in the halo of M31. We compare our method to the standard method of Fourier decomposition and find that the method of…

(Abridged) Low-mass stars have been recognised as promising targets in the search for rocky, small planets with the potential of supporting life. Doppler search programmes using high-resolution spectrographs like HARPS or HARPS-N are…

Stellar loci are widely used for selection of interesting outliers, reddening determinations, and calibrations. However, hitherto the dependence of stellar loci on metallicity has not been fully explored and their intrinsic widths are…

We explore the stellar metallicity distribution function of the Galactic halo based on SDSS ugriz photometry. A set of stellar isochrones is calibrated using observations of several star clusters and validated by comparisons with…

We present the metallicity distribution of a sample of 471 RR Lyrae (RRL) stars in the Sculptor dSph, obtained from the $I$-band Period-Luminosity relation. It is the first time that the early chemical evolution of a dwarf galaxy is…

We present new statistical parallax solutions for the absolute magnitude and kinematics of RR Lyrae stars. New proper motion, radial velocity, and abundance data are used; the new data set is 50% larger, and of higher quality, than…

We present results of the analysis of 70 RR Lyrae stars located in the bar of the Large Magellanic Cloud (LMC). Combining spectroscopically determined metallicity of these stars from the literature with precise periods from the OGLE III…