Related papers: Distance Scale Zero-Points from Galactic RR Lyrae …
(abridged) New photometry and spectroscopy for more than a hundred RR Lyrae stars in two fields located close to the bar of the Large Magellanic Cloud (LMC) are used to derive new accurate estimates of the average magnitude, the local…
Full space velocities are computed for a sample of 130 nearby RR Lyrae variables using both ground-based and Hipparcos proper motions. In many cases proper motions from multiple sources have been averaged to produce a significant…
We report the results of CCD V and R photometry of the RR Lyrae stars in M2. The periodicities of most variables are revised and new ephemerides are calculated. Light curve decomposition of the RR Lyrae stars was carried out and the…
(Abridged) We present the results of a new search for variable stars in the Local Group (LG) isolated dwarf galaxy IC1613, based on 24 orbits of F475W and F814W photometry from the ACS camera onboard the HST. We detected 259 candidate…
The universality of the Cepheid Period-Luminosity relations has been under discussion since metallicity effects have been assumed to play a role in the value of the intercept and, more recently, of the slope of these relations. The goal of…
Classical Cepheids (CCs) are at the heart of the empirical extragalactic distance ladder. Milky Way CCs are the only stars of this class accessible to trigonometric parallax measurements. Until recently, the most accurate trigonometric…
Utilizing Zwicky Transient Facility (ZTF) data and existing RR Lyrae stars (RRLs) catalogs, this study achieves the first calibration of the $P - \phi_{31} - R_{21} - \text{[Fe/H]}$ and $P-\phi_{31}-A_{2}-A_{1}-\text{[Fe/H]}$ relations in…
We use the multi-epoch K$\rm _S$ band observations, covering a $\sim$5 years baseline to obtain milli and sub-milli arcsec precision astrometry for a sample of eighteen previously known high proper motion sources, including precise…
We present an independent examination of the parallax zero-point of the Third Gaia Early Data Release (hereafter EDR3), using the LAMOST primary red clump (PRC) stellar sample. A median parallax offset of around $26 \mu$as, slightly larger…
Mira variables, RR Lyrae variables, and type II Cepheids all represent evolved states of low-mass stars, and long term observations have revealed that changes in pulsation period occur for each of these classes of variable. Most Mira…
We investigate the radial velocity (RV) variability and spectroscopic binarity of 19 Galactic long-period ($P_{\rm{puls}} \gtrsim 10$ d) classical Cepheid variable stars whose trigonometric parallaxes are being measured using the Hubble…
Draco dwarf Spheroidal galaxy (dSph) is one of the nearest and the most dark matter dominated satellites of the Milky Way. We obtained multi-epoch near-infrared (NIR, $JHK_s$) observations of the central region of Draco dSph covering a sky…
We present new theoretical period-luminosity-metallicity (PLZ) relations for RR Lyrae stars (RRL) at Spitzer and WISE wavelengths. The PLZ relations were derived using nonlinear, time-dependent convective hydrodynamical models for a broad…
Revised Hipparcos parallaxes for classical Cepheids are analysed together with 10 HST-based parallaxes (Benedict et al.). In a reddening-free V,I relation we find that the coefficient of logP is the same within the uncertainties in our…
We present absolute parallaxes and relative proper motions for five AM CVn stars, which we obtained using the Fine Guidance Sensors on board the Hubble Space Telescope. Our parallax measurements translate into distances d(AM CVn)=606+135-93…
Old-aged stellar distance indicators are present in all Galactic structures (halo, bulge, disk) and in galaxies of all Hubble types and, thus, are immensely powerful tools for understanding our Universe. Here we present a comprehensive…
We report on the analysis of ~22,000 M dwarfs using a statistical parallax method. This technique employs a maximum-likelihood formulation to simultaneously solve for the absolute magnitude, velocity ellipsoid parameters and reflex solar…
The distance to the Galactic center inferred from OGLE RR Lyrae variables observed in the direction of the bulge is Ro=8.1+-0.6 kpc. An accurate determination of Ro is hindered by countless effects that include an ambiguous extinction law,…
We present the first results of an near-ultraviolet (NUV) survey of RR Lyrae stars from the Ultraviolet Optical Telescope (UVOT) aboard the Swift Gamma-Ray Burst Mission. It is well-established that RR Lyrae have large amplitudes in the…
We present the detection of 6,371 RR Lyrae (RRL) stars distributed across ~14,000 deg^2 of the sky from the combined data of the Sloan Digital Sky Survey (SDSS), the Panoramic Survey Telescope and Rapid Response System 1 (PS1), and the…