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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.
| Improved Astrometry and Photometry for the Luyten Catalog. II. Faint Stars and the Revised Catalog
We complete construction of a catalog containing improved astrometry andnew optical/infrared photometry for the vast majority of NLTT starslying in the overlap of regions covered by POSS I and by the secondincremental Two Micron All Sky Survey (2MASS) release, approximately 44%of the sky. The epoch 2000 positions are typically accurate to 130 mas,the proper motions to 5.5 mas yr-1, and the V-J colors to0.25 mag. Relative proper motions of binary components are measured to 3mas yr-1. The false-identification rate is ~1% for11<~V<~18 and substantially less at brighter magnitudes. Theseimprovements permit the construction of a reduced proper-motion diagramthat, for the first time, allows one to classify NLTT stars intomain-sequence (MS) stars, subdwarfs (SDs), and white dwarfs (WDs). We inturn use this diagram to analyze the properties of both our catalog andthe NLTT catalog on which it is based. In sharp contrast to popularbelief, we find that NLTT incompleteness in the plane is almostcompletely concentrated in MS stars, and that SDs and WDs are detectedalmost uniformly over the sky δ>-33deg. Our catalogwill therefore provide a powerful tool to probe these populationsstatistically, as well as to reliably identify individual SDs and WDs.
| Multiplicity among solar-type stars. III. Statistical properties of the F7-K binaries with periods up to 10 years
Two CORAVEL radial velocity surveys - one among stars in the solarneighbourhood, the other in the Pleiades and in Praesepe - are merged toderive the statistical properties of main-sequence binaries withspectral types F7 to K and with periods up to 10 years. A sample of 89spectroscopic orbits was finally obtained. Among them, 52 relate to afree-of-bias selection of 405 stars (240 field stars and 165 clusterstars). The statistics corrected for selection effects yield thefollowing results: (1) No discrepancy is found between the binariesamong field stars and the binaries in open cluster. The distributions ofmass ratios, of periods, the period-eccentricity diagram and the binaryfrequencies are all within the same error intervals. (2) Thedistribution of mass ratios presents two maxima: a broad peak from q ~0.2 to q ~ 0.7, and a sharp peak for q > 0.8 (twins). Both arepresent among the early-type as well as among the late-type part of thesample, indicating a scale-free formation process. The peak for q >0.8 gradually decreases when long-period binaries are considered.Whatever their periods, the twins have eccentricities significantlylower than the other binaries, confirming a difference in the formationprocesses. Twins could be generated by in situ formation followed byaccretion from a gaseous envelope, whereas binaries with intermediatemass ratios could be formed at wide separations, but they are madecloser by migration led by interactions with a circumbinary disk. (3)The frequency of binaries with P<10 years is about 14%. (4) About0.3% of binaries are expected to appear as false positives in a planetsearch. Therefore, the frequency of planetary systems among stars ispresently 7+4-2%. The extension of thedistribution of mass ratios in the planetary range would result in avery sharp and very high peak, well separated from the binary stars withlow mass ratios. Based on photoelectric radial-velocity measurementscollected at Haute-Provence observatory and on observations made withthe ESA Hipparcos astrometry satellite.
| Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
The Catalogue, available at the Centre de Données Stellaires deStrasbourg, consists of 13 573 records concerning the results obtainedfrom different methods for 7778 stars, reported in the literature. Thefollowing data are listed for each star: identifications, apparentmagnitude, spectral type, apparent diameter in arcsec, absolute radiusin solar units, method of determination, reference, remarks. Commentsand statistics obtained from CADARS are given. The Catalogue isavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcar?J/A+A/367/521
| Photometric Measurements of the Fields of More than 700 Nearby Stars
In preparation for optical/IR interferometric searches for substellarcompanions of nearby stars, we undertook to characterize the fields ofall nearby stars visible from the Northern Hemisphere to determinesuitable companions for interferometric phase referencing. Because theKeck Interferometer in particular will be able to phase-reference oncompanions within the isoplanatic patch (30") to about 17th magnitude atK, we took images at V, r, and i that were deep enough to determine iffield stars were present to this magnitude around nearby stars using aspot-coated CCD. We report on 733 fields containing 10,629 measurementsin up to three filters (Gunn i, r and Johnson V) of nearby stars down toabout 13th magnitude at V.
| The ROSAT all-sky survey catalogue of the nearby stars
We present X-ray data for all entries of the Third Catalogue of NearbyStars \cite[(Gliese & Jahreiss 1991)]{gli91} that have been detectedas X-ray sources in the ROSAT all-sky survey. The catalogue contains1252 entries yielding an average detection rate of 32.9 percent. Inaddition to count rates, source detection parameters, hardness ratios,and X-ray fluxes we also list X-ray luminosities derived from Hipparcosparallaxes. Catalogue also available at CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.
| The importance of surface inhomogeneities for K and M dwarf chromospheric fluxes
We present published and archived spectroscopic and spectrophotometricdata of H-alpha, Ca II, Mg II, and X-rays for a large sample of K and Mdwarfs. The data set points to the importance that surfaceinhomogeneities have in the flux luminosity diagrams in these late-typedwarfs, irrespective of whether the Balmer lines are in emission orabsorption. Although supporting the fact that cooler stars exhibitincreasing levels of surface activity, evident through an increasingincidence of Balmer emission, surface inhomogeneities, or variations inthe local temperature and density structure, at the chromospheric level,dominate the total Ca II and Mg II fluxes. We show that the flux-fluxand luminosity-luminosity relations indicate differing extents ofinhomogeneity from the chromosphere through to the corona. A goodcorrelation between Ca II and Mg II fluxes indicates that they areformed in overlapping regions of the chromosphere, so that thecontribution of surface inhomogeneities is not evident from thisparticular flux-flux diagram. In the region of the upper chromospherethrough to the transition and corona, the correlation between Ly-alphaand X-ray fluxes indicates regions with similar levels of arealinhomogeneity. This appears to be uncorrelated with that at thechromospheric level.
| Photographic astrometry of binary and proper-motion stars. VII
Parallax data and mass ratios are presented for astrometric binaries andproper-motion stars. Three new unresolved red dwarf binaries are listedand annotated.
| H-alpha photometry of dwarf K and M stars - Chromospheric activity
H-alpha photometry of 118 K and M dwarfs are presented, with H-alphaequivalent width measures accurate to about 0.05 A. The data arecombined with the spectroscopic surveys of Stauffer and Hartmann (1986)and Fleming et al. (1988) to study the main features of thechromospheric activity versus mass relation for low-mass stars. An upperbound to the H-alpha equivalent width is found to be a function of themass relation (R-I). H-alpha luminosities and surface fluxes arecalculated for active stars, showing that both quantities generallydecline with R-I. The upper bound to the fraction of a star's bolometricluminosity, however, is independent of R-I. The results suggest that thechromospheres of most dMe stars with R-I less than 1.1 are in anactivity-saturated state. Also, H-alpha variability, probably due toflares, is detected in several stars.
| Dwarf K and M stars of high proper motion found in a hemispheric survey
A recently completed visual/red spectral region objective-prism surveyof more than half the sky found some 2200 dwarf K and M stars ofnegligible proper motion (Stephenson, 1986). The present paper adds the1800-odd spectroscopically identified dwarfs that did prove to havesignificant proper motions. About half of these had previous spectralclassifications of some sort, especially by Vyssotsky (1952, 1956). Forthe great majority, the present coordinates are more accurate thanprevious data. The paper includes about 50 stars with unpublishedparallaxes, likely to have parallaxes of 0.05 arcsec or more. Combiningthe present data with the first paper suggests that the number oflow-proper-motion stars in that paper was not unreasonable.
| 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.
| Predicted infrared brightness of stars within 25 parsecs of the sun
Procedures are given for transforming selected optical data intoinfrared flux densities or irradiances. The results provide R, T(eff)blackbody approximations for about 2000 of the stars in Woolley et al.'sCatalog of Stars (1970) within 25 pc of the sun, and additional whitedwarfs, with infrared flux densities predicted for them at ninewavelengths from 2.2 to 101 microns including the Infrared AstronomySatellite bands.
| Catalogue of stars with CaII H and K emissions
Not Available
| Spectral types for proper motion stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975AJ.....80..239B&db_key=AST
| The luminosity law for late-type main-sequence stars in the solar neighborhood
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974PASP...86..697E&db_key=AST
| Spectroscopic Observations of the Hyades Spectroscopic Binary BD +24°692
Abstract image available at:http://adsabs.harvard.edu/abs/1974PASP...86...59Y
| Catalog of Indidual Radial Velocities, 0h-12h, Measured by Astronomers of the Mount Wilson Observatory
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJS...19..387A&db_key=AST
| Calcium emission intensities as indicators of stellar age.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970MNRAS.148..463W&db_key=AST
| Radial velocities of dK and dM stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1967AJ.....72..905W&db_key=AST
| Dwarf M stars found spectrophotometrically .
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1956AJ.....61..201V&db_key=AST
| Magnitudes and colours of 123 stars in the neighbourhood of the Sun
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1954MNRAS.114..218Y&db_key=AST
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Datos observacionales y astrométricos
| Constelación: | Dragón |
| Ascensión Recta: | 09h26m53.13s |
| Declinación: | +75°56'03.3" |
| Magnitud Aparente: | 9.021 |
| Distancia: | 20.064 parsecs |
| Movimiento Propio en Ascensión Recta: | -345.9 |
| Movimiento Propio en Declinación: | -95.1 |
| B-T magnitude: | 10.532 |
| V-T magnitude: | 9.146 |
Catálogos y designaciones:
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