Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc-The Southern Sample
We are obtaining spectra, spectral types, and basic physical parametersfor the nearly 3600 dwarf and giant stars earlier than M0 in theHipparcos catalog within 40 pc of the Sun. Here we report on resultsfor 1676 stars in the southern hemisphere observed at Cerro TololoInter-American Observatory and Steward Observatory. These resultsinclude new, precise, homogeneous spectral types, basic physicalparameters (including the effective temperature, surface gravity, andmetallicity [M/H]), and measures of the chromospheric activity of ourprogram stars. We include notes on astrophysically interesting stars inthis sample, the metallicity distribution of the solar neighborhood, anda table of solar analogs. We also demonstrate that the bimodal nature ofthe distribution of the chromospheric activity parameterlogR'HK depends strongly on the metallicity, andwe explore the nature of the ``low-metallicity'' chromosphericallyactive K-type dwarfs.
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Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
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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.
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Revised Coordinates and Proper Motions of the Stars in the Luyten Half-Second Catalog
We present refined coordinates and proper-motion data for the highproper-motion (HPM) stars in the Luyten Half-Second (LHS) catalog. Thepositional uncertainty in the original Luyten catalog is typicallygreater than 10" and is often greater than 30". We have used the digitalscans of the POSS I and POSS II plates to derive more accurate positionsand proper motions of the objects. Out of the 4470 candidates in the LHScatalog, 4323 objects were manually reidentified in the POSS I and POSSII scans. A small fraction of the stars were not found because of thelack of finder charts and digitized POSS II scans. The uncertainties inthe revised positions are typically ~2" but can be as high as ~8" in afew cases, which is a large improvement over the original data.Cross-correlation with the Tycho-2 and Hipparcos catalogs yielded 819candidates (with mR<~12). For these brighter sources, theposition and proper-motion data were replaced with the more accurateTycho-2/Hipparcos data. In total, we have revised proper-motionmeasurements and coordinates for 4040 stars and revised coordinates for4330 stars. The electronic version of the paper5 contains the updated information on all 4470stars in the LHS catalog.
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Late-type members of young stellar kinematic groups - I. Single stars
This is the first paper of a series aimed at studying the properties oflate-type members of young stellar kinematic groups. We concentrate ourstudy on classical young moving groups such as the Local Association(Pleiades moving group, 20-150Myr), IC 2391 supercluster (35Myr), UrsaMajor group (Sirius supercluster, 300Myr), and Hyades supercluster(600Myr), as well as on recently identified groups such as the Castormoving group (200Myr). In this paper we compile a preliminary list ofsingle late-type possible members of some of these young stellarkinematic groups. Stars are selected from previously established membersof stellar kinematic groups based on photometric and kinematicproperties as well as from candidates based on other criteria such astheir level of chromospheric activity, rotation rate and lithiumabundance. Precise measurements of proper motions and parallaxes takenfrom the Hipparcos Catalogue, as well as from the Tycho-2 Catalogue, andpublished radial velocity measurements are used to calculate theGalactic space motions (U, V, W) and to apply Eggen's kinematic criteriain order to determine the membership of the selected stars to thedifferent groups. Additional criteria using age-dating methods forlate-type stars will be applied in forthcoming papers of this series. Afurther study of the list of stars compiled here could lead to a betterunderstanding of the chromospheric activity and their age evolution, aswell as of the star formation history in the solar neighbourhood. Inaddition, these stars are also potential search targets for directimaging detection of substellar companions.
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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
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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
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Astrometric positions of stars with high proper motions in the Southern Hemisphere
Several stars with large proper motions, cited by W.J. Luyten, wereincluded in the preliminary programme for the HIPPARCOS mission. Whenperforming preparatory measurements of plates, difficulties wereencountered in identifying certain of these stars when relying only onpublished coordinates. We have taken advantage of this work whichrelates to the southern sky in order to determine the astrometricposition of the greatest possible number of these objects, even forthose which were not included in the programme. Catalogue is onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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The Palomar/MSU Nearby Star Spectroscopic Survey.II.The Southern M Dwarfs and Investigation of Magnetic Activity
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996AJ....112.2799H&db_key=AST
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The Stellar Content of Star Stream I
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996AJ....111.1615E&db_key=AST
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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.
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The low mass Hyades and the evaporation of clusters
The 135 single stars and 85 binary systems, redder than R-I = +0.34 magand brighter than V = 17 mag, between alpha = 3.75 h and 5.0 h and delta= +5 deg and + 25 deg show a luminosity function that differsconsiderably from that of the general field stars within 20 pc of theSun. The ratio of double star components to single cluster membersincreases markedly with decreasing luminosity. Forty-three single starsand 16 binary systems that are members of the Hyades supercluster within20 pc of the Sun show the same luminosity function as the field stars inthat region. Fifty percent of the cluster members and 40 percent of thesupercluster members are components of binary stars. The equivalentwidths of H-alpha appear to support a range of ages (approximately 8 to16 x 108 yr) for the cluster stars and demonstrate that theoldest objects are in the supercluster. A list of cluster members, whichmay include the end of the stable main sequence, but for which accurate(R-I) photometry is not available, is included. The half-dozen knownparallax stars of the faintest luminosity contain at least onesupercluster member, TVLM 868-110639, which is probably beyond thestable, nuclear burning main sequence as a 'transitional' or 'brown'dwarf.
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The kinematics of young disk population supercluster members
A discussion of the total space motions of early-type members of youngdisk population superclusters, derived from distances based on aphotometric calibration of four-color and H-beta photometry, shows anincrease in total velocity with increasing radial distance from the sun,within each supercluster. The rate of increase with distance varies fromsupercluster to supercluster because it results from the interaction oftwo effects - an 'expansion' that involves the total space motion and a'rotation' that involves only the V-velocity because it arises from therequirement that supercluster members have isoperiodic, galactic orbits.The ratio of the velocity in the direction of galactic rotation(V-velocity) to the total space motion determines the size of theresultant effect from the contradictory 'rotation' and 'expansion'terms. The expansion term is 40 to 45 km's/kpc in the superclustersdiscussed, whereas the rotation term is dV/dX = -(b-A) = 26 km/s/kpc,where B and A are the constants of galactic rotation.
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The IC 2391 supercluster
Sixty-three field stars and the sparse cluster IC 2391 have beenidentified as members of the IC 2391 supercluster. The members have atleast 95 percent of their space motion, directed toward (A,D) = (5.82h,- 12.44d). Like members of the very similar Pleiades supercluster, theIC 2391 supercluster contains objects of two ages: t = 8 x 19 exp 7 and2.5 x 10 exp 8 yr. A prototype very active chromosphere star and theenigmatic giant variable TZ For are supercluster members together withtwo A-type stars suspected of possessing particulate disks. Anespecially interesting member is the system of Xi Cep (HR 8417) in whichthe two brightest components are greatly undermassive.
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Catalogue of Variable or Suspected Stars Nearby the Sun
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1990A&AS...85..971P&db_key=AST
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BVRI photometry of the Gliese Catalogue stars
Photoelectri BVRI photometry on the Cousins (Kron-Cape) system has beenobtained for many of the southern faint stars in the Gliese Catalog(1969). This extends the work of Cousins (1980) and provides a uniformset of data for the nearby stars. Several red dwarfs are noted, whichwere used to define the red end of the Cousins system.
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New Variable Star of the Globular Cluster M4
G46 is the fifth new variable star of the globular cluster M4 found bythe authors. Its period is 0d.264489, the amplitude in bluecolor is 0m.26, and it is a RRc Lyrae star. The angulardistance from the center of the cluster of G46 is about 2arcmin.2.
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Luminosities, abundances, and motions of stars brighter than visual magnitude 15.1 and annual proper motions larger than one-half arcsecond
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1987AJ.....93..393E&db_key=AST
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Catalog of proper-motion stars. III - Stars brighter than visual magnitude 15.1, south of declination +30 deg, and with annual proper motion between 0.5 and 0.7 arcsec
A catalog of (VRI) photometry for the some one thousand stars withannual proper motion between 0.5 and 0.7 arcsec, brighter than visualmagnitude 15.1, and south of declination +30 deg is presented. Theavailable proper-motion and radial-velocity data are also summarized.
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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.
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Relations between spectral types, absolute magnitudes, and colour indices of red dwarfs in the Cousins photometric system
Abstract image available at:http://adsabs.harvard.edu/abs/1984A&A...132..385T
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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.
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Trigonometric parallaxes for Southern Hemisphere stars
Ninety-three parallax solutions for 83 Southern Hemisphere stars arepresented which had previously been unpublished, or appeared only in the1952 or 1963 editions of the General Catalogue of Trigonometric StellarParallaxes. These data are now being published in preparation for thenew edition of the Catalogue.
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Note on the Photometric Properties of Red Dwarfs in the Cousins VRI System
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1981A&AS...46..105T&db_key=AST
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DDO Observations of Southern Stars
Not Available
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VRI photometry of nearby stars.
Not Available
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A photoelectric measurement of magnesium for late-type stars
A photoelectric index of MgH + Mg b for late-type stars has been createdby the addition of one filter bandpass to the DDO system. Measurementsshow that this index has good sensitivity to surface gravity for Kstars, and suggest that it can differentiate metal-poor halo giants fromdisk stars. From this index, involving measurement through two filtersalone, it appears that membership can be determined for stars on thegiant branch of globular clusters. It is possible that the index couldbe used, after calibration with cluster giants, to determine ages ofgiant stars in the field.
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M dwarfs: band strengths in halo and disk populations.
Abstract image available at:http://adsabs.harvard.edu/abs/1976ApJ...207..535M
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Variabilite D'etoiles Naines Rouges
Not Available
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Optical polarization of stars of galactic latitudes b-45 degres.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976A&AS...23..125S&db_key=AST
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INHABITED SKY
