Contents
Images
Upload your image
DSS Images Other Images
Related articles
A Catalog of Visual Double and Multiple Stars With Eclipsing Components
A new catalog of visual double systems containing eclipsing binaries asone component is presented. The main purpose of this catalog is tocompile a complete list of all known multiples of this variety, both forcurrent analysis and to highlight those in need of additionalobservations. All available photometric and astrometric data wereanalyzed, resulting in new orbits for eight systems and new times ofminimum light for a number of the eclipsing binaries. Some of thesystems in the catalog have acceptable solutions for their visualorbits, although in most cases their orbital periods are too long forsimultaneous analysis. Also included, however, are a number of systemswhich currently lack an orbital solution but which may be suitable forsimultaneous analysis in the future.
| Radial Velocity Studies of Close Binary Stars. XV
Radial velocity (RV) measurements and sine curve fits to the orbital RVvariations are presented for the last eight close binary systemsanalyzed in the same way as in the previous papers of this series: QXAnd, DY Cet, MR Del, HI Dra, DD Mon, V868 Mon, ER Ori, and Y Sex. Foranother seven systems (TT Cet, AA Cet, CW Lyn, V563 Lyr, CW Sge, LV Vir,and MW Vir), phase coverage is insufficient to provide reliable orbitsbut RVs of individual components were measured. Observations of a fewcomplicated systems observed throughout the David Dunlap Observatory(DDO) close binary program are also presented; among them is anespecially interesting multiple system V857 Her which—in additionto the contact binary—very probably contains one or more subdwarfcomponents of much earlier spectral type. All suspected binaries whichwere found to be most probably pulsating stars are briefly discussed interms of mean RVs and projected rotation velocities (vsin i) as well asspectral-type estimates. In two of them, CU CVn and V752 Mon, thebroadening functions show a clear presence of nonradial pulsations. Thepreviously missing spectral types for Paper I are given here in additionto such estimates for most of the program stars of this paper.Based on the data obtained at the David Dunlap Observatory, Universityof Toronto, Toronto, Canada.
| A catalogue of chromospherically active binary stars (third edition)
The catalogue of chromospherically active binaries (CABs) has beenrevised and updated. With 203 new identifications, the number of CABstars is increased to 409. The catalogue is available in electronicformat where each system has a number of lines (suborders) with a uniqueorder number. The columns contain data of limited numbers of selectedcross references, comments to explain peculiarities and the position ofthe binarity in case it belongs to a multiple system, classicalidentifications (RS Canum Venaticorum, BY Draconis), brightness andcolours, photometric and spectroscopic data, a description of emissionfeatures (CaII H and K, Hα, ultraviolet, infrared),X-ray luminosity, radio flux, physical quantities and orbitalinformation, where each basic entry is referenced so users can go to theoriginal sources.
| New absolute magnitude calibrations for detached binaries
Lutz-Kelker bias corrected absolute magnitude calibrations for thedetached binary systems with main-sequence components are presented. Theabsolute magnitudes of the calibrator stars were derived at intrinsiccolours of Johnson-Cousins and 2MASS (Two Micron All Sky Survey)photometric systems. As for the calibrator stars, 44 detached binarieswere selected from the Hipparcos catalogue, which have relative observedparallax errors smaller than 15% (σπ/π≤0.15).The calibration equations which provide the corrected absolute magnitudefor optical and near-infrared pass bands are valid for wide ranges ofcolours and absolute magnitudes: -0.18<(B-V)0<0.91,-1.6
| A catalogue of eclipsing variables
A new catalogue of 6330 eclipsing variable stars is presented. Thecatalogue was developed from the General Catalogue of Variable Stars(GCVS) and its textual remarks by including recently publishedinformation about classification of 843 systems and making correspondingcorrections of GCVS data. The catalogue1 represents thelargest list of eclipsing binaries classified from observations.
| A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)
The LSPM catalog is a comprehensive list of 61,977 stars north of theJ2000 celestial equator that have proper motions larger than 0.15"yr-1 (local-background-stars frame). The catalog has beengenerated primarily as a result of our systematic search for high propermotion stars in the Digitized Sky Surveys using our SUPERBLINK software.At brighter magnitudes, the catalog incorporates stars and data from theTycho-2 Catalogue and also, to a lesser extent, from the All-SkyCompiled Catalogue of 2.5 million stars. The LSPM catalog considerablyexpands over the old Luyten (Luyten Half-Second [LHS] and New LuytenTwo-Tenths [NLTT]) catalogs, superseding them for northern declinations.Positions are given with an accuracy of <~100 mas at the 2000.0epoch, and absolute proper motions are given with an accuracy of ~8 masyr-1. Corrections to the local-background-stars propermotions have been calculated, and absolute proper motions in theextragalactic frame are given. Whenever available, we also give opticalBT and VT magnitudes (from Tycho-2, ASCC-2.5),photographic BJ, RF, and IN magnitudes(from USNO-B1 catalog), and infrared J, H, and Ks magnitudes(from 2MASS). We also provide an estimated V magnitude and V-J color fornearly all catalog entries, useful for initial classification of thestars. The catalog is estimated to be over 99% complete at high Galacticlatitudes (|b|>15deg) and over 90% complete at lowGalactic latitudes (|b|>15deg), down to a magnitudeV=19.0, and has a limiting magnitude V=21.0. All the northern starslisted in the LHS and NLTT catalogs have been reidentified, and theirpositions, proper motions, and magnitudes reevaluated. The catalog alsolists a large number of completely new objects, which promise to expandvery significantly the census of red dwarfs, subdwarfs, and white dwarfsin the vicinity of the Sun.Based on data mining of the Digitized Sky Surveys (DSSs), developed andoperated by the Catalogs and Surveys Branch of the Space TelescopeScience Institute (STScI), Baltimore.Developed with support from the National Science Foundation (NSF), aspart of the NASA/NSF NStars program.
| Up-to-Date Linear Elements of Eclipsing Binaries
About 1800 O-C diagrams of eclipsing binaries were analyzed and up-todate linear elements were computed. The regularly updated ephemerides(as a continuation of SAC) are available only in electronic form at theInternet address: http://www.as.ap.krakow.pl/ephem/.
| Kinematics of chromospherically active binaries and evidence of an orbital period decrease in binary evolution
The kinematics of 237 chromospherically active binaries (CABs) werestudied. The sample is heterogeneous with different orbits andphysically different components from F to M spectral-type main-sequencestars to G and K giants and supergiants. The computed U, V, W spacevelocities indicate that the sample is also heterogeneous in velocityspace. That is, both kinematically younger and older systems exist amongthe non-evolved main sequence and the evolved binaries containing giantsand subgiants. The kinematically young (0.95 Gyr) subsample (N= 95),which is formed according to the kinematical criteria of moving groups,was compared with the rest (N= 142) of the sample (3.86 Gyr) toinvestigate any observational clues of binary evolution. Comparing theorbital period histograms between the younger and older subsamples,evidence was found supporting the finding of Demircan that the CABs losemass (and angular momentum) and evolve towards shorter orbital periods.The evidence of mass loss is noticeable on the histograms of the totalmass (Mh+Mc), which is compared between theyounger (only N= 53 systems available) and older subsamples (only N= 66systems available). The orbital period decrease during binary evolutionis found to be clearly indicated by the kinematical ages of 6.69, 5.19and 3.02 Gyr which were found in the subsamples according to the periodranges of logP<= 0.8, 0.8 < logP<= 1.7 and 1.7 < logP<=3, respectively, among the binaries in the older subsample.
| Reduction of CCD observations of visual binaries using the ``Tepui'' function as PSF
429 CCD measurements of relative positions and magnitude differences inV and R photometric bands for 165 visual double and multiple stars aregiven. CCD frames were taken at the 1.52 m Spanish telescope of theSpanish-German Center of Astronomy at Calar Alto (Almería,Spain). During the reduction process a ``Tepui" function was used as thePSF function.Tables 1 and 2 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/416/811
| A systematic study of X-ray variability in the ROSAT all-sky survey
We present a systematic search for variability among the ROSAT All-SkySurvey (RASS) X-ray sources. We generated lightcurves for about 30 000X-ray point sources detected sufficiently high above background. For ourvariability study different search algorithms were developed in order torecognize flares, periods and trends, respectively. The variable X-raysources were optically identified with counterparts in the SIMBAD, theUSNO-A2.0 and NED data bases, but a significant part of the X-raysources remains without cataloged optical counterparts. Out of the 1207sources classified as variable 767 (63.5%) were identified with stars,118 (9.8%) are of extragalactic origin, 10 (0.8%) are identified withother sources and 312 (25.8%) could not uniquely be identified withentries in optical catalogs. We give a statistical analysis of thevariable X-ray population and present some outstanding examples of X-rayvariability detected in the ROSAT all-sky survey. Most prominent amongthese sources are white dwarfs, apparently single, yet neverthelessshowing periodic variability. Many flares from hitherto unrecognisedflare stars have been detected as well as long term variability in theBL Lac 1E1757.7+7034.The complete version of Table 7 is only available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/403/247
| New Times of Minima of Eclipsing Binary Systems
We present several photoelectric minima observations of 7 eclipsingbinaries.
| First Photometric Observations of MR Delphini
Not Available
| Absolute dimensions of solar-type eclipsing binaries. I. uvby light curves for HS Aqr, KX Aqr, AL Ari, V963 Cen, MR Del, NY Hya, DU Leo, UW LMi, and V358 Pup
We present complete uvby light curves of 9 recently discovered eclipsingbinaries having late F, G, and K type components within or near themain-sequence band. They are the first results from a long term programcarried out since 1994 at the Strömgren Automatic Telescope at ESO,La Silla. The aim is to provide the accurate absolute dimensions forsolar-type stars needed for critical tests of the correspondingtheoretical models. A serious dilemma appears to be present in thecomparison of predictions from current stellar models with fundamentalproperties of known 0.7-1.1 Msun eclipsing binaries (Popper\cite{dmp97b}, Clausen et al. \cite{granada99b}). Spectroscopicobservations of the 9 eclipsing binaries are either available or arebeing obtained, and detailed analyses of the individual systems will bepublished in a series of subsequent papers. The light curves wereobtained as part of a systematic search for new eclipsing systems amonga large sample of (mostly) spectroscopic binaries. Catalogues of theextensive uvby and beta photometry from this search will be publishedseparately. Based on observations carried out with the StrömgrenAutomatic Telescope (SAT) at ESO, La Silla, Chile. When the individualanalyses are finished, Tables 12-20 will gradually be made available inelectronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/374/980
| Speckle observations of binary systems measured by Hipparcos
From speckle observations made with the PISCO speckle camera at the Picdu Midi Observatory, we present high angular resolution astrometric datafor 43 binary stars already observed by the Hipparcos satellite. Thissample consists of mainly new Hipparcos eclipsing binaries with a visualcompanion closer than one arcsecond, chosen with the aim to study thedynamical implications of a third component on the observationalparameters of the eclipsing system. In addition, we also included aselection of close visual binaries with few speckle data in order toanalyse possible systematic departures between the speckle and thenon-speckle orbits. The reduction method and the results are presentedin detail. For the close visual binaries we confront our observationswith the ephemerides based on the best known orbits. For the wide visualbinaries the confrontation is made directly with the Hipparcos data. Ourobservations are consistent both with previous speckle data and withmost of the Hipparcos measurements. Based on observations made with theTélescope Bernard Lyot at the Pic du Midi Observatory, France andon data obtained by the Hipparcos astrometry satellite. This work hasalso made use of the Simbad database, operated at CDS, Strasbourg,France.
| Two-colour photometry for 9473 components of close Hipparcos double and multiple stars
Using observations obtained with the Tycho instrument of the ESAHipparcos satellite, a two-colour photometry is produced for componentsof more than 7 000 Hipparcos double and multiple stars with angularseparations 0.1 to 2.5 arcsec. We publish 9473 components of 5173systems with separations above 0.3 arcsec. The majority of them did nothave Tycho photometry in the Hipparcos catalogue. The magnitudes arederived in the Tycho B_T and V_T passbands, similar to the Johnsonpassbands. Photometrically resolved components of the binaries withstatistically significant trigonometric parallaxes can be put on an HRdiagram, the majority of them for the first time. Based on observationsmade with the ESA Hipparcos satellite.
| Classification of EUV stellar sources detected by the ROSAT WFC. I. Photometric and radial velocity studies
We present the results of high-precision UBV(RI)_c photometricobservations and of spectroscopic radial velocity measurements obtainedat the European Southern Observatory for a sample of 51 cool starsdetected in the EUV by the ROSAT Wide Field Camera (WFC). Using alsorecent results from HIPPARCOS, we infer spectral types and investigatethe single or binary nature of the sample stars. Optical variability,with periods in the 0.4-13 day range, has been detected for the firsttime in 15 of these stars. based on data collected at the EuropeanSouthern Observatory, La Silla, Chile.}\fnmsep \thanks{Tables 1--5,Figs. 2-27 and the complete data set are available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr or viahttp://cdsweb.u-strasbg.fr/Abstract.html}
| Speckle Interferometry at the US Naval Observatory. III.
Position angles and separations resulting from 2578 speckleinterferometric observations of 590 binary stars are tabulated. This isthe third in a series of papers presenting measures obtained using the66 cm refractor at the US Naval Observatory in Washington, DC, andcovers the period from 1995 June through 1996 December. Program starsrange in separation from 0.2" to 4.3", with a limiting magnitude ofV=11. Random errors are estimated to be 17.0 mas in separation and0.56d/rho in position angle, where rho is the separation in arcseconds.These are the first results acquired using an improved intensified CCDdetector. The new detector, in concert with an intensity-filteringtechnique applied in software, has permitted a 1 mag increase in dynamicrange, to 3.5 mag, for pairs separated by about 2". The instrumentationand calibration are briefly described, with an emphasis on thecharacteristics of the new detector. The software filter used toincrease the dynamic range is also described.
| Speckle Interferometry at the US Naval Observatory. II.
Position angles and separations resulting from 2406 speckleinterferometric observations of 547 binary stars are tabulated. This isthe second in a series of papers presenting measures obtained using the66 cm refractor at the US Naval Observatory in Washington, DC, with anintensified CCD detector. Program stars range in separation from 0.2" to3.8", with Deltam<=2.5 mag and a limiting magnitude of V=10.0. Theobservation epochs run from 1993 January through 1995 August. Randomerrors are estimated to be 14 mas in separation and 0.52d/rho inposition angle, where rho is the separation in arcseconds. Theinstrumentation and calibration are briefly described. Aspects of thedata analysis related to the avoidance of systematic errors are alsodiscussed.
| The 74th Special Name-list of Variable Stars
We present the Name-list introducing GCVS names for 3153 variable starsdiscovered by the Hipparcos mission.
| HIPPARCOS Parallaxes of Eclipsing Binaries and the Radiative Flux Scale
Eclipsing binaries with Hipparcos parallaxes are found to define aradiative flux relation for main-sequence stars in the B6-F0 range aboutas well as stars with angular diameters and to extend the range to F8.The fluxes of components of binaries showing large intrinsic variationsfall well below the curve for other stars and its extension to lowertemperatures. Angular diameters of main-sequence stars obtained with thenew generation of stellar interferometers should improve and extend theflux calibration. Based on data from the ESA Hipparcos satellite.
| Discovery of two short-period eclipsing binaries with active components.
We present high-precision UBV(RI)_c_ photometry as well as soft X-raylight curves for the visual triple system HD 9770 and the visual binaryHD 195434, obtained at the European Southern Observatory and extractedfrom the ROSAT all-sky survey, respectively. The optical photometryrevealed that in both systems one component is a very short-periodeclipsing binary showing also BY Dra-type variability. We have computedaccurate orbital periods, deduced approximate physical parameters,spectral classifications, distances and X-ray luminosities andidentified which component of each visual system is responsible for theoptical variability. Futhermore, we find that both systems are variablein X-rays, but no correlation with the optical variability is seen.
| Optical identification of EUV sources from the ROSAT Wide Field Camera all-sky survey
Optical identifications for 195 EUV sources located in the ROSAT WideField Camera all-sky survey are presented. We list 69 previously unknownEUV-emitting white dwarfs, 114 active stars, 7 new magnetic cataclysmicvariables and 5 active galaxies. Several of the white dwarfs haveresolved M-type companions, while five are unresolved white dwarf/M-starpairs. Finding charts are given for the optical counterparts.
| The ROSAT Wide Field Camera all-sky survey of extreme-ultraviolet sources - II. The 2RE Source Catalogue
During 1990-1991 the Wide Field Camera (WFC) on the ROSAT satelliteperformed the first all-sky survey at EUV wavelengths. The survey wasconducted in two `colours' using broad-band filters to define wavebandscovering the ranges 60-140 A and 112-200 A. It was fully imaging, witheffective spatial resolution of about 3 arcmin FWHM, and point sourcelocation accuracy of typically better than 1 arcmin. From an initialanalysis, Pounds et al. published the WFC Bright Source Catalogue (BSC)of 383 sources. In this paper we report results from reprocessing of thecomplete survey database; the resulting list of sources is the `2RE'Catalogue. It contains 479 sources, of which 387 are detected in bothsurvey wavebands, a significant advance on the BSC (80 per cent versus60 per cent). Improvements over the original BSC include: (i) betterrejection of poor aspect periods, and smaller random errors in theaspect reconstruction; (ii) improved background screening; (iii)improved methods for source detection; (iv) inclusion of atime-variability test for each source; (v) more extensive investigationof the survey sensitivity. We define the catalogue selection criteria,and present the catalogue contents in terms of tables and sky maps. Wealso discuss the sky coverage, source number-flux relations, opticalidentifications and source variability.
| A survey of proper motion stars. 12: an expanded sample
We report new photometry and radial velocities for almost 500 stars fromthe Lowell Proper Motion Catalog. We combine these results with ourprior sample and rederive stellar temperatures based on the photometry,reddening, metallicities (using chi squared matching of our 22,500 lowSignal to Noise (S/N) high resolution echelle spectra with a grid ofsynthetic spectra), distances, space motions, and Galactic orbitalparameters for 1269 (kinematics) and 1261 (metallicity) of the 1464stars in the complete survey. The frequency of spectroscopic binariesfor the metal-poor ((m/H) less than or equal to -1.2) stars with periodsshorter than 3000 days is at least 15%. The spectroscopic binaryfrequency for metal-rich stars ((m/H) greater than -0.5) appears to belower, about 9%, but this may be a selection effect. We also discussspecial classes of stars, including treatment of the double-linedspectroscopic binaries, and identification of subgiants. Four possiblenew members of the class of field blue stragglers are noted. We pointout the detection of three possible new white dwarfs, six broad-lined(binary) systems, and discuss briefly the three already knownnitrogen-rich halo dwarfs. The primary result of this paper will beavailable on CD-ROM, in the form of a much larger table.
| New subdwarfs. IV - UBV photometry of 1690 high-proper-motion stars
A photometric list of 1690 stars of known high proper motion is used tosearch for potential high-velocity stars of various metallicity valuesin order to find candidates for trigonometric programs on subdwarfs andto enlarge the sample with which to study the relation between stellarkinematics and metal abundance. A list of 113 stars with tangentialspace velocities of 300 km/s or greater is obtained, the highesttangential velocity relative to the sun being 630 km/s. By using thevariation of the tangential velocity with longitude and adopting thegalactic rotation at the solar circle to be 220 km/s, the rotation ofthe subdwarf system is estimated at 0 + or - 50 km/s from the transversevelocity alone, in agreement with determinations based on other methods.
| G. P. Kuiper's spectral classifications of proper-motion stars
Spectral classifications are listed for over 3200 stars, mainly of largeproper motion, observed and classified by Kuiper during the years1937-1944 at the Yerkes and McDonald Observatories. While Kuiper himselfpublished many of his types, and while improved classifications are nowavailable for many of these stars, much of value remains. For many ofthe objects, no other spectral data exist.
| Double star measures at Lick Observatory, Mount Hamilton, California.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978PASP...90..465H&db_key=AST
| UBV photometry of large proper motion stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973PASP...85..358M&db_key=AST
| Lowell proper motions II : proper motion survey of the Northern Hemisphere with the 13-inch photographic telescope of the Lowell Observatory
Not Available
| Micrometer measures of double stars.
Not Available
|
Submit a new article
Related links
Submit a new link
Member of following groups:
|
Observation and Astrometry data
| Constellation: | Delphinus |
| Right ascension: | 20h31m13.51s |
| Declination: | +05°13'08.7" |
| Apparent magnitude: | 9.409 |
| Proper motion RA: | 303.2 |
| Proper motion Dec: | 275.3 |
| B-T magnitude: | 10.41 |
| V-T magnitude: | 9.492 |
Catalogs and designations:
|
