Related papers: Problems encountered in the Hipparcos variable sta…
We present the initial results of a 40 night contiguous ground-based campaign of time series photometric observations of a 1.39 sq. deg field located within the NASA Kepler mission field of view. The goal of this pre-launch survey was to…
Gaia Data Release 2 (Gaia DR2) contains results for 1693 million sources in the magnitude range 3 to 21 based on observations collected by the European Space Agency Gaia satellite during the first 22 months of its operational phase. We…
We have used deep V-band and JHKs-band observations to investigate variability and stellar populations near the Galactic plane in Centaurus, and compared the observations with the Galactic model of Besancon. By applying image subtraction…
Regular large-scale polarimetric observations in Crimean astrophysical observatory began in the early 1960s. In 2002 - 2017 the single-channel aperture photometer-polarimeter with a quarter-wave plate at the 2.6-m Shajn mirror telescope…
In this paper we develop an analytical expression relating the sensitivity to a periodic signal to the duration and accuracy of a given set of data. The effects of windowing are explored, and also the sensitivity to periods longer than the…
We analyzed the Hipparcos astrometric observations of 47 stars that were discovered to harbor giant planets and 14 stars with brown-dwarf secondary candidates. The Hipparcos measurements were used together with the corresponding stellar…
Direct observations of gravitational waves will open in the near future new windows on the Universe. Among the expected sources, instabilities of rotating compact astrophysical objects are waited to be detected with some impatience as this…
This contribution is intended as a `rough guide' to the Hipparcos Catalogue for the non-expert user. Some general aspects of the use of astrometric data are discussed as well as Hipparcos-specific applications. We discuss when and at what…
A photometric study of variable stars in the field of old open cluster NGC 188 is discussed. Observations were carried out in two bands R and I for 5513 stars up to R = 17 mag in the field of 1.5 x 1.5 grad. around the cluster. The…
This study aims to assess the properties and classification of 62 variable stars in Cygnus, little studied since their discovery and originally reported in the Information Bulletin on Variable Stars (IBVS) 1302. Using data from previous…
We transformed radial velocities compiled from more than 1400 published sources, including the Geneva--Copenhagen survey of the solar neighborhood (CORAVEL-CfA), into a uniform system based on the radial velocities of 854 standard stars in…
Context.The Gaia Early Data Release 3 contained the positions, parallaxes and proper motions of 1.5 billion sources, among which some did not fit well the "single star" model. Binarity is one of the causes of this. Aims. Four million of…
A magnitude limited population of 18 808 Hipparcos stars is used to calibrate distances for 52 794 RAVE stars, including dwarfs, giants, and pre-main sequence stars. I give treatments for a number of types of bias affecting calculation,…
A new all-sky catalogue of all available uvbybeta measurements from the literature was generated. The uvbybeta photometric system is widely used for the study of various Galactic and extragalactic objects. It measures the colour due to…
We present results on parallaxes, magnitudes and proper motions for 17 optically identified massive X-ray binaries (MXRB) which were observed during the Hipparcos astrometry mission. This sample includes the sources detected in the…
The orbits of five single-lined spectroscopic binaries have recently been determined. We now use astrometric measurements that were collected with the Hipparcos satellite to constrain the systems' mass ratios and secondary masses. The…
We search for the astrometric signatures of planets and brown dwarfs known from radial velocity surveys in the improved Hipparcos intermediate astrometric data provided by van Leeuwen (2007a). Our aim is to put more significant constraints…
We present a set of companion dynamical masses and orbital parameters of seven star systems from the NEID Earth Twin Survey with significant absolute astrometric accelerations between the epochs of Hipparcos and Gaia. These include four…
We describe observations and abundance analysis of a high-resolution, high-S/N survey of 168 stars, most of which are metal-poor dwarfs. We follow a self-consistent LTE analysis technique to determine the stellar parameters and abundances,…
Gaia is undertaking a deep synoptic survey of the Galaxy, but photometry from individual epochs has, as of yet, only been released for a minimal number of sources. We show that it is possible to identify variable stars in Gaia Data Release…