Related papers: The Wilson--Bappu Effect: a tool to determine stel…
We propose and apply a test that can detect any systematic errors in the Hipparcos parallaxes towards the Hyades cluster at the level of 0.3 mas. We show that the statistical parallax method subsumes the classical moving cluster methods and…
The average near-infrared (K-band) luminosity of 238 Hipparcos red clump giants is derived and then used to measure the distance to the Galactic center. These Hipparcos red clump giants have been previously employed as I-band standard…
We demonstrate a new Bayesian technique to invert color-magnitude diagrams of main sequence and white dwarf stars to reveal the underlying cluster properties of age, distance, metallicity, and line-of-sight absorption, as well as individual…
Observational tests of stellar and Galactic chemical evolution call for the joint knowledge of a star's physical parameters, detailed element abundances, and precise age. For cool main-sequence (MS) stars the abundances of many elements can…
In this second paper of a series on the accuracy and precision of the determination of age and metallicity of simple stellar populations (SSPs) by means of the full spectrum fitting technique, we study the influence of star cluster mass…
Hipparcos parallax measurements of stars in the Pleiades notoriously result in a cluster distance of 118 pc; ~10% shorter than the `classical' results of MS-fitting. In an earlier paper we developed a purely empirical MS-fitting method to…
We perform a measurement of the mass--richness relation of the redMaPPer galaxy cluster catalogue using weak lensing data from the Sloan Digital Sky Survey. We have carefully characterized a broad range of systematic uncertainties,…
We have derived a new photographic photometry and proper motions for 20000 stars with completeness to V = 18 in the direction of galactic center at the intermediate latitude (l = 3 deg,b = 47 deg; alpha(1950)=15h 18m, delta(1950) = +02deg…
The average of 14 recent measurements of the distance to the Large Magellanic Cloud (LMC) implies a true modulus of 18.50 +- 0.02 mag, and demonstrates a trend in the past 2 years of convergence toward a standard value. The distance…
With positive signals from multiple direct detection experiments it will, in principle, be possible to measure the mass and cross sections of weakly-interacting massive particle (WIMP) dark matter. Recent work has shown that, with a…
We use the clump giants of the disk as standard candles calibrated from Hipparcos parallaxes in order to map their distribution with two new near-IR surveys of the Galactic plane: UKIDSS-GPS and VVV. We explore different selection cuts of…
The weak gravitational lensing effect, small coherent distortions of galaxy images by means of a gravitational tidal field, can be used to study the relation between the matter and galaxy distribution. In this context, weak lensing has so…
The $2$-Wasserstein distance is sensitive to minor geometric differences between distributions, making it a very powerful dissimilarity metric. However, due to this sensitivity, a small outlier mass can also cause a significant increase in…
We determine the period-magnitude relations of RR Lyrae stars in 13 photometric bandpasses from 0.4 to 12 {\mu}m using timeseries observations of 134 stars. The Bayesian formalism, extended from our previous work to include the effects of…
Knowledge of late K and M dwarf metallicities can be used to guide planet searches and constrain planet formation models. However, the determination of metallicities of late-type stars is difficult because visible wavelength spectra of…
The weak distortions produced by gravitational lensing in the images of background galaxies provide a method to measure directly the distribution of mass in the universe. However this technique requires high precision measurements of the…
Determining the expansion of the universe, i.e. the Hubble constant (H0) to better than 2% is required in order to understand the nature of dark energy. However, the two most accurate methods to do it, the cosmic microwave background and…
We establish an empirical effective temperature calibration of main sequence, luminosity class V to III B-type stars for the Delta a photometric system which was originally developed to detect magnetic chemically peculiar objects of the…
We estimated the Galactic model parameters by means of a new approach based on the comparison of the observed space density functions per absolute magnitude interval with a unique density law for each population individually, and via the…
Interstellar dust presents a significant challenge to extending parallax-determined distances of optically observed pulsational variables to larger volumes. Distance ladder work at mid-infrared wavebands, where dust effects are negligible…