Related papers: Improved Baade-Wesselink surface-brightness relati…

Homogeneous photometric data (Johnson V, B-V, V-K, Cousins V-I and Stromgren b-y), radial velocities, and abundances of Fe, O, Mg, Si, Ca, Ti, Cr and Ni are presented for 99 stars with high precision parallaxes measured by the Hipparcos…

Surface brightness asymmetries are a very common feature of stars. Among other effects they cause a difference between the projected barycentre and photocentre. The evolution of those surface features makes this difference time-dependent.…

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…

A new extensive grid of synthetic Str{\"o}mgren colors and bolometric corrections is presented for F-M type dwarf and giant stars having 3000K $\leq$ T$_{\rm{eff}}$ $\leq$ 8000K, 0.0 $\leq$ log $g$ $\leq$ 5.0, and -3.0 $\leq$ [Fe/H] $\leq$…

We have determined new relations between $UBV$ colors and mass-to-light ratios ($M/L$) for dwarf irregular (dIrr) galaxies, as well as for transformed $g^\prime - r^\prime$. These $M/L$ to color relations (MLCRs) are based on stellar mass…

It has been suggested that giant planet occurrence peaks for stars with $M_{\ast}~\approx~3~M_{\odot}$ at a value a factor of 4 higher than observed for solar-mass stars. This population of giant planets predicted to frequently orbit…

Blue Supergiants (BSGs) are the brightest stars in the universe at visual light with absolute magnitudes up to Mv=-10 mag. They are ideal stellar objects for the determination of extragalactic distances, in particular, because the perennial…

We present Spitzer IRAC photometry of white dwarf remnants of 14 stars with M = 3-5 Msol. We do not detect mid-infrared excess around any of our targets. By demanding a 3 sigma photometric excess at 4.5 micron for unresolved companions, we…

Most known white dwarfs in multiple systems with main sequence stars have been discovered with M-type companions, because the white dwarf causes detectable UV excess and bluer colors than expected from a single M star. Surveys have shown…

We describe the use of partially overlapping galaxies to provide direct measurements of the effective absorption in galaxy disks, independent of assumptions about internal disk structure. The non-overlapping parts of the galaxies and…

We measure the size-luminosity relation of photometrically-selected galaxies within the redshift range $z\sim6-9$, using galaxies lensed by six foreground Hubble Frontier Fields (HFF) clusters. The power afforded by strong gravitational…

From recent reports on terrestrial heavy ion collision experiments it appears that one may not obtain information about the existence of asymptotic freedom (AF) and chiral symmetry restoration (CSR) for quarks of QCD at high density. This…

In anticipation of the VLT/SPHERE planet imager guaranteed time programs, we have conducted a preparatory survey of 86 stars between 2009 and 2013 in order to identify new faint comoving companions to ultimately carry out a comprehensive…

Using SDSS Data Release 6, we construct two independent samples of candidate stellar wide binaries selected as i) pairs of unresolved sources with angular separation in the range 3'' - 16'', ii) common proper motion pairs with 5'' - 30''…

The dust-content of damped Lyman-alpha systems (DLAs) is an important observable for understanding their origin and the neutral gas reservoirs of galaxies. While the average colour-excess of DLAs, E(B-V), is known to be <15 milli-magnitudes…

We have determined a dust-free colour-magnitude (CM) relation for spiral galaxies, by using I-K colours in edge-on galaxies above the plane. We find that the scatter in this relation is small and approximately as large as can be explained…

We present evidence for a positive angular correlation between bright submillimetre sources and low-redshift galaxies. The study was conducted using 39 sources selected from 3 contiguous, flux-limited SCUBA surveys, cross-correlated with…

Based on CHARA Array measurements, we present the angular diameters of 23 nearby, main- sequence stars, ranging from spectral type A7 to K0, five of which are exoplanet host stars. We derive linear radii, effective temperatures, and…

Masses are one of the most difficult stellar properties to measure. In the case of the white-dwarf companions of Barium stars, the situation is worse. These stars are dim, cool, and difficult to observe via direct methods. However, Ba stars…

We present a spatially resolved analysis of four star-forming galaxies at $z = 4.44-5.64$ using data from the JWST PRIMER and ALMA-CRISTAL surveys to probe the stellar and inter-stellar medium properties on the sub-kpc scale. In the…