497 datasets found

We present a spectroscopic survey of a sample of F stars that have not yet been searched for planets. The observations of 187 stars obtained with the Bochum Echelle...

We present the results of a search for infrared-excess (IR-excess) candidates in a comprehensive (29000 stars) magnitude-limited sample of dwarf stars, spanning the spectral...

Using the Position and Proper Motion Extended-L (PPMXL) catalogue, we have used optical and near-infrared colour cuts together with a reduced proper motion cut to find bright M...

We report the discovery of 76 new T dwarfs from the UKIRT Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS). Near-infrared broad- and narrow-band photometry and...

The spectroscopic catalogue of white dwarf main-sequence (WDMS) binaries from the Sloan Digital Sky Survey (SDSS) is the largest and most homogeneous sample of compact binary...

M dwarfs are the most numerous stars in the Galaxy. They are characterized by strong magnetic activity. The ensuing high-energy emission is crucial for the evolution of their...

In this paper, a summary of optical time-series photometry of 125 ultracool dwarfs is given. The observing strategy was to monitor each object continuously for 2-3h in order to...

We develop optical and near-infrared colour-selection criteria based on the model colours of binaries consisting of a white dwarf and a main-sequence star. Using our...

We present a detailed spectroscopic study of 93 solar-type stars that are targets of the NASA/Kepler mission and provide detailed chemical composition of each target. We find...

We present the results of the first search for ultracompact dwarfs (UCDs) in the Perseus cluster core, including the region of the cluster around the unusual brightest cluster...

We use 665 high-resolution spectra for 60 different dM4 stars and 1088 high-resolution spectra for 97 different dK5 stars from the European Southern Observatory (ESO) and...

We present the first white dwarf mass distributions of a large and homogeneous sample of post-common envelope binaries (PCEBs) and wide white dwarf main-sequence (WDMS) binaries...

We present here the final results of the first spectropolarimetric survey of a small sample of active M dwarfs, aimed at providing observational constraints on dynamo action on...

We identify 806 ultracool dwarfs (of which 34 are newly discovered L dwarfs) from their Sloan Digital Sky Survey (SDSS) riz photometry and obtain proper motions through...

We present a catalogue of 1602 white-dwarf-main-sequence (WDMS) binaries from the spectroscopic Sloan Digital Sky Survey Data Release 6 (SDSS DR6). Among these, we identify 440...

We associate 132 low-mass ultracool dwarfs in the southern hemisphere as candidate members of five moving groups (MGs) using photometric and astrometric selection techniques. Of...

The UK Infrared Telescope Infrared Deep Sky Survey (UKIDSS) is the first of a new generation of infrared surveys. Here, we combine the data from two UKIDSS components, the Large...

By using images taken with Wide Field Camera (WFCAM) on United Kingdom Infrared Telescope (UKIRT) and Son of ISAAC (SofI) on the New Technology Telescope (NTT) and combining...

We empirically determine effective temperatures and bolometric luminosities for a large sample of nearby M dwarfs, for which high accuracy optical and infrared photometry is...

The proper motion measurements for 142 previously known L and T dwarfs are presented. From this sample we identify and discuss eight high-velocity L dwarfs. We also find four...