Search Publications
Fundamental parameters and infrared excesses of Hipparcos stars
Zijlstra, A. A.; Boyer, M. L.; McDonald, I.
We derive the fundamental parameters (temperature and luminosity) of 107 619 Hipparcos stars and place these stars on a true Hertzsprung-Russell diagram. This is achieved by comparing BT-SETTL model atmospheres to spectral energy distributions (SEDs) created from Hipparcos, Tycho, Sloan Digital Sky Survey, DENIS, Two Micron All Sky Survey, MSX, AK…
Accurate fundamental parameters and detailed abundance patterns from spectroscopy of 93 solar-type Kepler targets
Kawaler, S. D.; Christensen-Dalsgaard, J.; García, R. A. +29 more
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 that the overall metallicity is well represented by Fe lines. Relative abundances of light elements (CNO) and α elements are generally higher for low-metallicity stars. Our s…
Field O stars: formed in situ or as runaways?
Gvaramadze, V. V.; Pflamm-Altenburg, J.; Kroupa, P. +1 more
A significant fraction of massive stars in the Milky Way and other galaxies are located far from star clusters and star-forming regions. It is known that some of these stars are runaways, i.e. possess high space velocities (determined through the proper motion and/or radial velocity measurements), and therefore most likely were formed in embedded …
Discovery of the benchmark metal-poor T8 dwarf BD +01° 2920B
Marocco, F.; Homeier, D.; Pinfield, D. J. +20 more
We have searched the Wide-field Infrared Survey Explorer first data release for widely separated (≤10 000 au) late T dwarf companions to Hipparcos and Gliese stars. We have discovered a new binary system containing a K-band suppressed T8p dwarf WISEP J142320.86+011638.1 and the mildly metal poor ([Fe/H] =-0.38 ± 0.06) primary BD +01° 2920 (HIP 703…
Automated classification of Hipparcos unsolved variables
Rimoldini, L.; Mowlavi, N.; Nienartowicz, K. +14 more
We present an automated classification of stars exhibiting periodic, non-periodic and irregular light variations. The Hipparcos catalogue of unsolved variables is employed to complement the training set of periodic variables of Dubath et al. with irregular and non-periodic representatives, leading to 3881 sources in total which describe 24 variabi…
Identifying ultra-cool dwarfs at low Galactic latitudes: a southern candidate catalogue
Marocco, F.; Pinfield, D. J.; Jones, H. R. A. +6 more
We present an ultra-cool dwarf (UCD) catalogue compiled from low southern Galactic latitudes and mid-plane, from a cross-correlation of the Two Micron All-Sky Survey (2MASS) and the SuperCOSMOS survey. The catalogue contains 246 members identified from 5042 deg2 within 220° ≤ ℓ ≤ 360° and 0° < ℓ ≤ 30°, for |b| ≤ 15°. Sixteen candidat…
Revised and updated catalogue of the First Byurakan Survey of late-type stars
Gigoyan, K. S.; Mickaelian, A. M.
There have been 15 lists of late-type stars published between 1990 and 2010. These late-type stars have been found in the low-dispersion spectroscopic plates of the First Byurakan Survey (FBS). The systematic search and selection was carried out on a surface ∼16 000 deg2 on almost the whole area of the FBS. As a result, a comprehensive …
Alessi 95 and the short-period Cepheid SU Cassiopeiae
Gieren, W. P.; Alessi, B.; Storm, J. +6 more
The parameters for the newly discovered open cluster Alessi 95 are established on the basis of available photometric and spectroscopic data, in conjunction with new observations. Colour excesses for spectroscopically observed B- and A-type stars near SU Cas follow a reddening relation described by E(U-B)/E(B-V) = 0.83 + 0.02E(B-V), implying a valu…
Orbit determination of close binary systems using lucky imaging
Rica, F. M.; Barrena, R.; Vázquez, G. +2 more
We present relative positions of visual binaries observed in 2009 with the FastCam 'lucky-imaging' camera mounted on the 1.5-m Carlos Sánchez Telescope at the Observatorio del Teide. We obtained 424 CCD observations (averaged in 198 mean relative positions) of 157 binaries with angular separations in the range 0.14-15.40 arcsec, with a median sepa…
Observation and modelling of main-sequence star chromospheres - XIX. FIES and FEROS observations of dM1 stars
Houdebine, E. R.; Butler, C. J.; Telting, J. +1 more
We present 187 high-resolution spectra for 62 different M1 dwarfs from observations obtained with the FIbre-fed Echelle Spectrograph (FIES) on the Nordic Optical Telescope (NOT) and from observations with the Fibre-fed Extended Range Echelle Spectrograph (FEROS) from the European Southern Observatory (ESO) data base. We also compiled other measure…