Survey for Transiting Extrasolar Planets in Stellar Systems. II. Spectrophotometry and Metallicities of Open Clusters
We present metallicity estimates for seven open clusters based onspectrophotometric indices from moderate-resolution spectroscopy.Observations of field giants of known metallicity provide a correlationbetween the spectroscopic indices and the metallicity of open clustergiants. We use χ2 analysis to fit the relation ofspectrophotometric indices to metallicity in field giants. The resultingfunction allows an estimate of the target-cluster giants' metallicitieswith an error in the method of +/-0.08 dex. We derive the followingmetallicities for the seven open clusters: NGC 1245, [M/H]=-0.14+/-0.04NGC 2099, [M/H]=+0.05+/-0.05 NGC 2324, [M/H]=-0.06+/-0.04 NGC 2539,[M/H]=-0.04+/-0.03 NGC 2682 (M67), [M/H]=-0.05+/-0.02 NGC 6705,[M/H]=+0.14+/-0.08 NGC 6819, [M/H]=-0.07+/-0.12. These metallicityestimates will be useful in planning future extrasolar planet transitsearches, since planets may form more readily in metal-richenvironments.
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The Indo-US Library of Coudé Feed Stellar Spectra
We have obtained spectra for 1273 stars using the 0.9 m coudéfeed telescope at Kitt Peak National Observatory. This telescope feedsthe coudé spectrograph of the 2.1 m telescope. The spectra havebeen obtained with the no. 5 camera of the coudé spectrograph anda Loral 3K×1K CCD. Two gratings have been used to provide spectralcoverage from 3460 to 9464 Å, at a resolution of ~1 Å FWHMand at an original dispersion of 0.44 Å pixel-1. For885 stars we have complete spectra over the entire 3460 to 9464 Åwavelength region (neglecting small gaps of less than 50 Å), andpartial spectral coverage for the remaining stars. The 1273 stars havebeen selected to provide broad coverage of the atmospheric parametersTeff, logg, and [Fe/H], as well as spectral type. The goal ofthe project is to provide a comprehensive library of stellar spectra foruse in the automated classification of stellar and galaxy spectra and ingalaxy population synthesis. In this paper we discuss thecharacteristics of the spectral library, viz., details of theobservations, data reduction procedures, and selection of stars. We alsopresent a few illustrations of the quality and information available inthe spectra. The first version of the complete spectral library is nowpublicly available from the National Optical Astronomy Observatory(NOAO) via ftp and http.
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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.
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Catalogs of temperatures and [Fe/H] averages for evolved G and K stars
A catalog of mean values of [Fe/H] for evolved G and K stars isdescribed. The zero point for the catalog entries has been establishedby using differential analyses. Literature sources for those entries areincluded in the catalog. The mean values are given with rms errors andnumbers of degrees of freedom, and a simple example of the use of thesestatistical data is given. For a number of the stars with entries in thecatalog, temperatures have been determined. A separate catalogcontaining those data is briefly described. Catalog only available atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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Broad-band JHK(L') photometry of a sample of giants with 0.5 > [Fe/H] > -3
We present the results of a three-year campaign of broad-band photometryin the near-infrared J, H, K and L' bands for a sample of approximately250 giant stars carried out at the Observatorio del Teide (Tenerife,Spain). Transformations of the Telescopio Carlos Sanchez systeminto/from several currently used infrared systems are extended to theredward part of the colour axis. The linearity of our photometric systemin the range -3 mag [Fe/H] >-3. Data of comparable quality previouslypublished have been added to the sample in order to increase thereliability of the relations to be obtained. We also provide mean IRcolours for giant stars according to spectral type.ables 1, 2 and 3 are only available in electronic form via the CDS(anonymous ftp 130.79.128.5 or http://cdsweb.u-strasbg.fr/Abstract.html
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A catalogue of [Fe/H] determinations: 1996 edition
A fifth Edition of the Catalogue of [Fe/H] determinations is presentedherewith. It contains 5946 determinations for 3247 stars, including 751stars in 84 associations, clusters or galaxies. The literature iscomplete up to December 1995. The 700 bibliographical referencescorrespond to [Fe/H] determinations obtained from high resolutionspectroscopic observations and detailed analyses, most of them carriedout with the help of model-atmospheres. The Catalogue is made up ofthree formatted files: File 1: field stars, File 2: stars in galacticassociations and clusters, and stars in SMC, LMC, M33, File 3: numberedlist of bibliographical references The three files are only available inelectronic form at the Centre de Donnees Stellaires in Strasbourg, viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5), or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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The integrated spectra of M32 and of 47 Tuc: A comparative study at high spectral resolution
Integrated spectra have been obtained for the elliptical galaxy M32 andfor the 'metal-rich' Galactic globular cluster 47 Tuc. The spectra coverthe wavelength interval lambda lambda 3800-4400 A at a resolution of 2.5A full width at half maximum (FWHM) and S/N ratio of approximately100:1. Similar data have been acquired for a library of 191 individualstars, and, to support the 47 Tuc observations, integrated spectra offour additional metal-rich Galactic globular clusters have beenobtained. These observations are used to compare in detail theintegrated spectra of M32 (the most extensively studied ellipticalgalaxy) and 47 Tuc (the best-studied metal-rich Galactic globularcluster). Although M32 and 47 Tuc have similar optical broadband colorsand overall spectral types, when viewed at 2.5 A resolution spectranumerous subtle differences between their integrated are clearlyvisible. A system of 13 spectral indices, many of them originallydefined in Rose (1984), has been used to quantify these differences.Altogether twelve diagnostic diagrams are presented to illustrate themanner in which the integrated spectrum of M32 differs from that of 47Tuc. These diagrams are used to place several strong constraints on thestellar populations in these two systems.
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Carbon isotope ratios and lithium abundances in old disk giants
C isotope ratios are here derived from CN red system features in 8000 ACCD spectra, together with Li abundances from the resonance doublet at6708 A, for stars of a previously studied sample of old disk giants. TheC isotope ratios of the old disk stars show a pronounced dependence onstellar luminosity, from C-12/C-13 values of above 40 in stars of M(V)greater than 1.8, to about 13 for those of M(V) below 1.8. The Liabundances assist in the discrimination of true old-disk giants fromthose which may belong to the young disk population. The great change inC-12/C-13 ratios occurring abruptly at M(V) of about 1.8 seems to beprimarily due to the first dredge-up.
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A catalogue of Fe/H determinations - 1991 edition
A revised version of the catalog of Fe/H determinations published by G.Cayrel et al. (1985) is presented. The catalog contains 3252 Fe/Hdeterminations for 1676 stars. The literature is complete up to December1990. The catalog includes only Fe/H determinations obtained from highresolution spectroscopic observations based on detailed spectroscopicanalyses, most of them carried out with model atmospheres. The catalogcontains a good number of Fe/H determinations for stars from open andglobular clusters and for some supergiants in the Magellanic Clouds.
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UBV photometry of stars whose positions are accurately known. VI
Results are presented from UBV photometric observations of 1000 stars ofthe Bright Star Catalogue and the faint extension of the FK5.Observations were carried out between July 1987 and December 1990 withthe 40-cm Cassegrain telescope of the Kvistaberg Observatory.
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A critical appraisal of published values of (Fe/H) for K II-IV stars
'Primary' (Fe/H) averages are presented for 373 evolved K stars ofluminosity classes II-IV and (Fe/H) values beween -0.9 and +0.21 dex.The data define a 'consensus' zero point with a precision of + or -0.018 dex and have rms errors per datum which are typically 0.08-0.16dex. The primary data base makes recalibration possible for the large(Fe/H) catalogs of Hansen and Kjaergaard (1971) and Brown et al. (1989).A set of (Fe/H) standard stars and a new DDO calibration are given whichhave rms of 0.07 dex or less for the standard star data. For normal Kgiants, CN-based values of (Fe/H) turn out to be more precise than manyhigh-dispersion results. Some zero-point errors in the latter are alsofound and new examples of continuum-placement problems appear. Thushigh-dispersion results are not invariably superior to photometricmetallicities. A review of high-dispersion and related work onsupermetallicity in K III-IV star is also given.
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The vertical structure of our galaxy. I - Methods of quantitative objective prism spectroscopy
The methods employed to determine the spectral types and log g and Fe/Hvalues for Galactic F-K stars in the vertical-structure investigation ofRose and Agustinho (1991) are described in detail. IIaO objective-prismplates obtained with the Curtis Schmidt telescope at CTIO using a 10-degprism and a 135-A FWHM interference filter centered at 408 nm aredigitized, and three spectral indices defined by Rose (1984) aremeasured and used to calculate the desired parameters. Results fromtests of the accuracy of this method are presented, and it is shown thatreliable separation of G dwarfs from G giants/subgiants is possible downto B = 13.
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Fifth fundamental catalogue. Part 2: The FK5 extension - new fundamental stars
The mean positions and proper motions for 3117 new fundamental starsessentially in the magnitude range about 4.5 to 9.5 are given in thisFK5 extension. Mean apparent visual magnitude is 7.2 and is on average2.5 magnitudes fainter then the basic FK5 which has a mean magnitude of4.7. (The basic FK5 gives the mean positions and proper motions for theclassical 1535 fundamental stars). The following are discussed: theobservational material, reduction of observations, star selection, andthe system for the FK5 extension. An explanation and description of thecatalog are given. The catalog of 3117 fundamental stars for the equinoxand epoch J2000.0 and B1950.0 is presented. The parallaxes and radialvelocities for 22 extension stars with large forecasting effects aregiven. Catalogs used in the compilation of the FK5 fundamental catalogare listed.
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Fourth preliminary catalogue of stars, right ascension observed with photoelectric transit instrument (PPCP4).
Not Available
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Spectroscopy of metal-rich M31 globular clusters
Integrated CCD spectra in the 3850-4200 A region were obtained for ninemetal-rich globular clusters in M31. The spectra are analyzed using thereddening-free spectral-classification system of Rose (1984). The dataare combined with data obtained by Rose and Tripicco (1986) for ninemetal-rich Galactic globular clusters and with spectra of 72 stars withwell-determined atmospheric parameters. It is found that the 4000 Alight from metal rich M31 globulars is dominated by dwarfs, while giantsand dwarfs contribute equally to the light from the mean of themetal-rich Galactic globulars. The contribution of early-type stars tothe 400 A light from M31 clusters is less than 5 percent in most cases.Also, the 3883 and 4216 CN bands in the M31 globulars are very strongfor their integrated spectral types. The results suggest that themetal-rich M31 globular clusters are much younger than Galacticmetal-rich clusters like 47 Tuc or M71.
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Metal-abundance determinations from near-UV spectra - Application to the mean metal abundance of M32
Near-UV spectra for the nucleus of the elliptical galaxy M32 and for 60field stars have been obtained which cover the wavelength interval3200-3900 A at a resolution of 2.5 A FWHM. A depression in thepseudocontinuum shortward of 3504 A is found to be quite sensitive tometal abundance. The results indicate that the luminosity-weighted meanmetal Fe/H abundance ratio for M32 at 3500 A is about -0.1, and that thegiant branch contributes slightly less than 30 percent of the light at4000 A. The luminosity-weighted N/Fe abundance ratio is shown to beapproximately equal to that of solar neighborhood stars.
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A detailed kinematic and abundance analysis of old disk giants
A semiautomated spectroscopic analysis of 34 evolved high-velocity giantstars confirms the conclusions of Lambert and Ries (1981) and Kjaergaardet al. (1982) that for old disk giants the C/N ratios have approximatelythe solar ratio, and that the O/Fe ratio is enhanced relative to thesun. The only evolutionary affect of the CNA abundances of these starsis the reduction in their C-12/C-13 ratio, and evolutionary consequencesare discussed in terms of the kinematic, mass and convective mixingcharacteristics of these objects.
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Transformation equations and other aids for VRI photometry
Transformations among VRI systems are commonly beset by Paschen-jumpeffects, for which fully satisfactory allowance has not previously beenmade. This paper describes two new techniques which are based on thework of Gutierrez-Moreno, and which allow fully for the effects of thePaschen jump. Values of E(V-R)/E(B-V) and E(R-I)/E(B-V) are also givenfor the Cousins system for a wide range of temperatures. These and thenew techniques contribute to a set of new transformation relations whichapply for most VRI systems; the status of the remaining systems isreviewed, and future work needed for them is described. Two majorsources of Cousins VRI data underlie the new relations; the consistencyof these sources is reviewed and found to be generally satisfactory,although more work on this question is needed. Finally, three tables oftransformed standard-star and other data are given for the Cousins andJohnson systems, and a description of ways to reproduce the latter ispresented.
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Red horizontal-branch stars in the galactic disk
A quantitative, three-dimensional spectral classification systemdeveloped by Rose (1984), which uses 2.5-A resolution spectra in theblue, has been used to identify a class of red horizontal branch (RHB)stars in the Galactic disk that are similar to those in the 'metal rich'globular cluster M 71. The RHB are denoted as evolved stars by their SrII 4077 line, and are distinguished from post-main sequence starsevolving through the same region of the HR diagram on the basis of theunique appearance of their CN 3883 and 4216 A bands. The RHB starsconsitute at least 5 percent of the entire giant branch population ofthe disk.
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Spectral anomalies in the Hyades and Pleiades and in field stars with active chromospheres
Widened photographic image-tube spectra at 50 A/mm dispersion have beenobtained for a large number of late-type field dwarfs and giants withwell-determined atmospheric parameters and for 35 Hyades dwarfs and 31Pleiades dwarfs. The observations and data analysis are discussed, and asummary of the quantitative spectral classification system is given.This system is used to compare the Hyades and Pleiades with field stars.The cluster stars are found to exhibit several anomalies with respect tothe field stars which are not readily explained either by abundance orsurface gravity peculiarities, or by the presence of cool starspots onthe strong Ca II emission stars, or by cool companions. It is proposedthat active regions on stars with strong Ca II emission reversals haveseriously affected many of the principal spectral lines.
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Determination of atmospheric parameters for G and K giants by means of photoelectric indices.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971A&A....15..123H&db_key=AST
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Abundances of sodium, magnesium and calcium in K-type giant stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1968MNRAS.140...21P&db_key=AST
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Red and infra-red magnitudes and colours for 300 F. G and K type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1967MNRAS.135...23A&db_key=AST
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Narrow band photometry in the study of stellar populations. I. The sodium D lines in late-type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966MNRAS.134..135P&db_key=AST
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Narrow band photoelectric Hα photometry in late-type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966MNRAS.133..449P&db_key=AST
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Photometry of the orange-red Ca I triplet in late-type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1964MNRAS.128..475P&db_key=AST
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Hα Photometry of late-type stars I. F, G and K-type stars north of the equator
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1964MNRAS.128..435P&db_key=AST
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UBV photometry of 300 G and K type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963MNRAS.125..557A&db_key=AST
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The magnesium b lines in late-type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1960MNRAS.121...52D&db_key=AST
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Photoelectric measurements of the λ4200 A CN band and the G band in G8-K5 spectra
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1960MNRAS.120..287G&db_key=AST
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INHABITED SKY
