Related papers: New absolute magnitude calibrations for detached b…
The surface brightness -- colour relation (SBCR) is a basic tool in establishing precise and accurate distances within the Local Group. Detached eclipsing binary stars with accurately determined radii and trigonometric parallaxes allow for…
We determine absolute dimensions and abundances for the three F-type main-sequence detached eclipsing binaries AD Boo, VZ Hya, and WZ Oph and perform a detailed comparison with results from recent stellar evolutionary models. uvby light…
We present the detailed fundamental stellar parameters of the close visual binary system; HD39438 for the first time. We used Al-Wardat's method for analyzing binary and multiple stellar systems (BMSSs). The method implements Kurucz's plane…
Absolute proper motions for $\sim$ 7.7 million objects were derived based on data from the South Galactic Cap u-band Sky Survey (SCUSS) and astrometric data derived from uncompressed Digitized Sky Surveys that the Space Telescope Science…
We present a new model-independent method to determine the spatial curvature and to mitigate the circularity problem affecting the use of quasars as distance indicators. The cosmic-chronometer measurements are used to construct the…
By reanalyzing the Hipparcos Intermediate Astrometric Data of a large sample of spectroscopic binaries containing a giant, we obtain a sample of 29 systems fulfilling a carefully derived set of constraints and hence for which we can derive…
We present new accurate CCD uvby light curves for the LMC eclipsing binaries HV982 and HV12578, and for the SMC systems HV1433 and HV11284 obtained at the Danish 1.5m telescope at ESO, La Silla. The light curves were derived from DoPHOT…
Using shape measurement techniques developed for weak lensing surveys we have identified three new ultracool binaries in the Pan-STARRS1 survey. Binary companions which are not completely resolved can still alter the shapes of stellar…
We present deep VI photometry of stars in the globular cluster M5 (NGC 5904) based on images taken with the Hubble Space Telescope. The resulting color-magnitude diagram reaches below V ~ 27 mag, revealing the upper 2-3 magnitudes of the…
A new method for absolute polarimetric calibration of large telescopes is presented. The proposed method is highly accurate and is based on the calibration of a small sub-aperture, which is then extended to the full system by means of…
Individual components of well-detached binary systems are assumed to be two single-like stars with a common origin, i.e. they share the same chemical composition and same age. Therefore, one expects to fit the observed parameters of both…
We sing the praises of the central limit theorem. Having previously removed all other possible causes of significant systematic error in the statistical parallax determination of RR Lyrae absolute magnitudes, we investigate systematic…
88 dwarfs, covering the colour index interval 0.37 <(B-V)o <= 1.07 mag, with metallicities -2.70 <= [Fe/H] <= +0.26 dex have been taken from three different sources for new metallicity calibration. The catalogue of Cayrel de Stroble et al.…
We performed a theoretical investigation on the mixing-length parameter recovery from an eclipsing double-lined binary system. We focused on a syntetic system composed by a primary of mass M = 0.95 Msun and a secondary of M = 0.85 Msun.…
Abridged. Eclipsing spectroscopic double-lined binaries are the prime source of precise and accurate measurements of masses and radii of stars. These measurements provide a stringent test of models of stellar evolution that are persistently…
Twin binaries were identified among the eclipsing binaries with $\delta$>--30$^\circ$ listed in the ASAS catalog. In addition to the known twin binaries in the literature, 68 new systems have been identified, photometric and spectroscopic…
We present near-IR images of five luminous quasars at z~2 and one at z~4 obtained with an experimental adaptive optics instrument at the ESO Very Large Telescope. The observations are part of a program aimed at demonstrating the…
We present the design and characterization of a ground-based absolute polarization angle calibrator accurate to better than 0.1 degrees for use with polarization sensitive cosmic microwave background (CMB) experiments. The calibrator's…
We present new B, V and I-band photometry for a sample of 43 local subdwarfs with HIPPARCOS parallax errors < 13%, in the metallicity range -1.0 < [Fe/H] < -0.3, which we use to perform main sequence (MS) fitting to the Galactic globular…
We present the results of the combined photometric and spectroscopic analysis of a bright (V=9.14), nearby (d=31 pc), late-type detached eclipsing binary AK Fornacis. This P=3.981 d system has not been previously recognised as a…