Lithium abundances and rotational behavior for bright giant stars
Aims.We study the links possibly existing between the lithium content ofbright giant stars and their rotational velocity. Methods: .Weperformed a spectral analysis of 145 bright giant stars (luminosityclass II) spanning the spectral range from F3 to K5. All these starshave homogeneous rotational velocity measurements available in theliterature. Results: .For all the stars of the sample, we provideconsistent lithium abundances (A_Li), effective temperatures (T_eff),projected rotational velocity (v sin i), mean metallicity ([Fe/H]),stellar mass, and an indication of the stellar multiplicity. The gradualdecrease in lithium abundance with T_eff is confirmed for bright giantstars, and it points to a dilution factor that is at least assignificant as in giant stars. From the F to K spectral types, the A_Lispans at least three orders of magnitude, reflecting the effects ofstellar mass and evolution on dilution. Conclusions: .We find thatthe behavior of A_Li as a function of v sin i in bright giant starspresents the same trend as is observed in giants and subgiants: starswith high A_Li are moderate or fast rotators, while stars with low A_Lishow a wide range of v sin i values.
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Evolved GK stars near the sun. I - The old disk population
A sample of nearly two thousand GK giants with intermediate band, (R,I),DDO and Geneva photometry has been assembled. Astrometric data is alsoavailable for most of the stars. The some 800 members of the old diskpopulation in the sample yield accurate luminosities (from two sources),reddening values and chemical abundances from calibrations of thephotometric parameters. Less than one percent of the objects arepeculiar in the sense that the flux distribution is abnormal. Thepeculiarity is signaled by strong CH (and Ba II) and weak CH. The CH+stars are all spectroscopic binaries, probably with white dwarfcompanions, whereas the CH- stars are not. A broad absorption band,centered near 3500 A, is found in the CH+ stars whereas the CH- objectshave a broad emission feature in the same region. The intensity of theseabsorptions and emissions are independent of the intensity of abnormalspectral features. Ten percent of the old disk sample have a heavyelement abundance from one and a half to three times the solar value.The distribution of the heavy element abundances is nearly a normal onewith a peak near solar abundance and ranges three times to one sixthsolar. The distribution of the (U, V) velocities is independent of theheavy element abundance and does not appear to be random. Ten percent ofthe old disk stars show a CN anomaly, equally divided between CN strongand CN weak. Several stars of individual astrometric or astrophysicalimportance are isolated.
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Uvby-Beta Photometry of E-Region Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1993A&AS..102..637J&db_key=AST
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Secondary standards for H-beta photometry in the Southern Hemisphere (second series).
Not Available
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UBV (RI)c standard stars in the E- and F-regions and in the Magellanic Clouds - a revised catalogue.
Not Available
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Large and kinematically unbiased samples of G- and K-type stars. IV - Evolved stars of the old disk population
Modified Stromgren and (R,I) photometry, along with DDO and Genevaphotometry, are presented for a complete sample of evolved old-disk Gand K giants in the Bright Star Catalogue. Stars with ages of between1.5 x 10 to the 9th and 10 to the 10th yr are found to have anear-normal distribution of heavy element abundances, centered on anFe/H abundance ratio of -0.1 dex. The old disk clusters NGC 3680 and IC4651 contain red-straggler young-disk giants that are probablycontemporaries of the blue stragglers in the clusters.
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Large and kinematically unbiased samples of G- and K-type stars. II - Observations of evolved stars in the Bright Star sample. III - Evolved young disk stars in the Bright Star sample
Four color and RI observations were obtained for a large sample ofG-type and K-type stars in the Bright Star Catalogue. Data are firstpresented for 110 evolved stars. Photometry of evolved young diskpopulation stars have then been calibrated for luminosity, reddening,and metallicity on the basis of results for members of the Hyades andSirius superclusters. New DDO results are given for 120 stars.
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Spectroscopy of V471 Tau. I - Review of basic properties
Spectroscopic observations of the eclipsing binary V471 Tau are reportedand analyzed. Data obtained mainly in the red band at Mt. WilsonObservatory and KPNO during the period 1975-1983 are compiled inextensive tables and graphs, and the radial velocity of the K dwarfcomponent is determined using a Griffin-mask technique. Resultsdiscussed include: (1) distance 44 + or - 6 pc, (consistent withmembership in the Hyades), (2) apparent period variation consistent witha third component, (3) emissionlike features affecting theradial-velocity determination, (4) transient features consistent withthe presence of flares, and (5) phase-coherent variation in H-alpha(attributed to the action of the white-dwarf Lyman continuum emission onthe K dwarf).
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Secondary standards for the Stromgren UVBY system
Observations of 158 E region stars have been made in the Stromgrensystem, using the 46-cm reflector at Cape Town. They are mostly brighterthan eighth magnitude and are intended for use as secondary standardsfor the four-color system. The E region relative zero points are definedwith a precision of + or - 0.001 mag, and the internal standard errorsof the colors life between + or - 0.001 and + or - 0.002 mag.
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UBVRI photometry of FK4 and FK4 supplement stars
Photometric UBVRI observations of 172 Southern Hemisphere stars of theFK4 and FK4-Supplement catalogs, obtained using a dry-ice-cooledphotomultiplier on the 50-cm telescope at ESO on 37 nights during1982-1983 are reported. The data are presented in tables and graphs andbriefly characterized.
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Differential population synthesis of early-type galaxies. I - Spectrophotometric atlas of synthesis standard spectra
Continuous spectrophotometry has been obtained for 200 objects at aresolution of 10-17 A over the wavelength region 3600-10,000 A.Kron-Cousins BVRI colors are computed from the spectra and compared withpublished photoelectric photometry. The (V - R)C color index is used togroup the individual observations to form synthesis standard spectra for48 common spectral types. The standard groups include a solar abundancesequence of most spectral types and luminosity classes, metal-rich andmetal weak G - K giant-branch sequences, and horizontal-branch giants.The variations with color, luminosity, and metallicity of severalprominent line strengths are discussed. The spectral atlas is availableas a FITS magnetic tape.
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Radial velocities of southern stars obtained with the photoelectric scanner CORAVEL. III - 790 late-type bright stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985A&AS...59...15A&db_key=AST
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UBV photometry of E region standard stars of intermediate brightness
Photometry data are given for 335 stars in the nine E regions.Observations were made using a photometer and filters on the 47 cmreflector at Cape Town. The stellar dispersions are summarized. Data arepresented in tabular form.
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UBVRI Standard Stars in the E-Regions
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1982PASP...94..244G&db_key=AST
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Photometric standard stars for the UBV and (RI)KC systems.
Not Available
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Fainter Standards for VRI Photometry in the E Regions
Not Available
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VRI standards in the E regions
Not Available
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The redshift-distance relation. VIII - Magnitudes and redshifts of southern galaxies in groups: A further mapping of the local velocity field and an estimate of the deceleration parameter
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975ApJ...202..563S&db_key=AST
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Standard Stars for VRI Photometry with S25 Response Photocathodes [Errata: 1974MNSSA..33....1C]
Not Available
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Lichtelektrische UBV-Photometrie von Standardsternen und in vier Sternfeldern am Äquator
Not Available
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Standard magnitudes in the E regions.
Not Available
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INHABITED SKY
