3D mapping of the dense interstellar gas around the Local Bubble
We present intermediate results from a long-term program of mapping theneutral absorption characteristics of the local interstellar medium,motivated by the availability of accurate and consistent parallaxes fromthe Hipparcos satellite. Equivalent widths of the interstellar NaID-line doublet at 5890 Å are presented for the lines-of-sighttowards some 311 new target stars lying within ~ 350 pc of the Sun.Using these data, together with NaI absorption measurements towards afurther ~ 240 nearby targets published in the literature (for many ofthem, in the directions of molecular clouds), and the ~ 450lines-of-sight already presented by (Sfeir et al. \cite{sfeir99}), weshow 3D absorption maps of the local distribution of neutral gas towards1005 sight-lines with Hipparcos distances as viewed from a variety ofdifferent galactic projections.The data are synthesized by means of two complementary methods, (i) bymapping of iso-equivalent width contours, and (ii) by densitydistribution calculation from the inversion of column-densities, amethod devised by Vergely et al. (\cite{vergely01}). Our present dataconfirms the view that the local cavity is deficient in cold and neutralinterstellar gas. The closest dense and cold gas ``wall'', in the firstquadrant, is at ~ 55-60 pc. There are a few isolated clouds at closerdistance, if the detected absorption is not produced by circumstellarmaterial.The maps reveal narrow or wide ``interstellar tunnels'' which connectthe Local Bubble to surrounding cavities, as predicted by the model ofCox & Smith (1974). In particular, one of these tunnels, defined bystars at 300 to 600 pc from the Sun showing negligible sodiumabsorption, connects the well known CMa void (Gry et al. \cite{gry85}),which is part of the Local Bubble, with the supershell GSH 238+00+09(Heiles \cite{heiles98}). High latitude lines-of-sight with the smallestabsorption are found in two ``chimneys'', whose directions areperpendicular to the Gould belt plane. The maps show that the LocalBubble is ``squeezed'' by surrounding shells in a complicated patternand suggest that its pressure is smaller than in those expandingregions.We discuss the locations of several HI and molecular clouds. Usingcomparisons between NaI and HI or CO velocities, in some cases we areable to improve the constraints on their distances. According to thevelocity criteria, MBM 33-37, MBM 16-18, UT 3-7, and MBM 54-55 arecloser than ~ 100 pc, and MBM 40 is closer than 80 pc. Dense HI cloudsare seen at less than 90 pc and 85 pc in the directions of the MBM 12and MBM 41-43 clouds respectively, but the molecular clouds themselvesmay be far beyond. The above closest molecular clouds are located at theneutral boundary of the Bubble. Only one translucent cloud, G192-67, isclearly embedded within the LB and well isolated.These maps of the distribution of local neutral interstellar NaI gas arealso briefly compared with the distribution of both interstellar dustand neutral HI gas within 300 pc.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/411/447
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Kinematics of Hipparcos Visual Binaries. II. Stars with Ground-Based Orbital Solutions
This paper continues kinematical investigations of the Hipparcos visualbinaries with known orbits. A sample, consisting of 804 binary systemswith orbital elements determined from ground-based observations, isselected. The mean relative error of their parallaxes is about 12% andthe mean relative error of proper motions is about 4%. However, even 41%of the sample stars lack radial velocity measurements. The computedGalactic velocity components and other kinematical parameters are usedto divide the stars with known radial velocities into kinematical agegroups. The majority (92%) of binaries from the sample are thin diskstars, 7.6% have thick disk kinematics and only two binaries have halokinematics. Among them, the long-period variable Mira Ceti has a verydiscordant {Hipparcos} and ground-based parallax values. From the wholesample, 60 stars are ascribed to the thick disk and halo population.There is an urgent need to increase the number of the identified halobinaries with known orbits and substantially improve the situation withradial velocity data for stars with known orbits.
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CCD Speckle Observations of Binary Stars from the Southern Hemisphere. III. Differential Photometry
Two hundred seventy-two magnitude difference measures of 135 double starsystems are presented. The results are derived from speckle observationsusing the Bessel V and R passbands and a fast readout CCD camera.Observations were taken at two 60 cm telescopes, namely the Helen SawyerHogg Telescope, formerly at Las Campanas, Chile, and the Lowell-TololoTelescope at the Cerro Tololo Inter-American Observatory, Chile. Thedata analysis method is presented and, in comparing the results to thoseof Hipparcos as well as to recent results using adaptive optics, we findvery good agreement. Overall, the measurement precision appears to bedependent on seeing and other factors but is generally in the range of0.10-0.15 mag for single observations under favorable observingconditions. In four cases, multiple observations in both V and R allowedfor the derivation of component V-R colors with uncertainties of 0.11mag or less. Spectral types are assigned and preliminary effectivetemperatures are estimated in these cases.
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ICCD Speckle Observations of Binary Stars. XXIII. Measurements during 1982-1997 from Six Telescopes, with 14 New Orbits
We present 2017 observations of 1286 binary stars, observed by means ofspeckle interferometry using six telescopes over a 15 year period from1982 April to 1997 June. These measurements constitute the 23dinstallment in CHARA's speckle program at 2 to 4 m class telescopes andinclude the second major collection of measurements from the MountWilson 100 inch (2.5 m) Hooker Telescope. Orbital elements are alsopresented for 14 systems, seven of which have had no previouslypublished orbital analyses.
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Micrometer Measurements of Southern Double Stars made at the National Observatory of Llano del Hato, Venezuela
This paper reports 151 micrometer measurements of 66 double starsobserved with the 65-cm refractor at the Venezuelan National Observatoryat Llano del Hato, Mérida, during February 1997 and February1998.
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The ROSAT all-sky survey catalogue of optically bright main-sequence stars and subgiant stars
We present X-ray data for all main-sequence and subgiant stars ofspectral types A, F, G, and K and luminosity classes IV and V listed inthe Bright Star Catalogue that have been detected as X-ray sources inthe ROSAT all-sky survey; several stars without luminosity class arealso included. The catalogue contains 980 entries yielding an averagedetection rate of 32 percent. In addition to count rates, sourcedetection parameters, hardness ratios, and X-ray fluxes we also listX-ray luminosities derived from Hipparcos parallaxes. The catalogue isalso available in electronic form via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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CCD Speckle Observations of Binary Stars From the Southern Hemisphere
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....114.2117H&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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Orbits of visual binaries
The paper presents orbit computations of 20 pairs of visual binarieswith recent reobservations in 1991.0-1992.5. Fourteen of the pairs wereobserved at Cerro Tololo; the other six were studied in connection withastrometric plate series.
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Observations of double stars and new pairs. XV
The study reports visual and photographic measures listed for 1150 pairsobtained in the time frame 1989.91-1992.15, including 221 new doublestars. Magnitudes were estimated for a part of the objects, especiallythe fainter ones. Plate orientations were calculated from field stars ofknown positions and were precessed to the epoch; numbers of nights andof measured exposures are given. Reobservation of faint, neglected pairsreveal many corrections to the data from the old discovery lists.
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Micrometric measurements of visual binaries (5th list)
The data resulting from 596 micrometric measurements of 152 binaries areset forth which represent observations taken on the GPO astrograph(described by Scardia, 1990). The traditional declination method is usedto track star position, and some of the measurements are related toprevious work by the author (1990). The data given include O-Cmeasurements corresponding to the Worley and Heintz catalogue (1984) andother relevant data.
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ICCD speckle observations of binary stars. V - Measurements during 1988-1989 from the Kitt Peak and the Cerro Tololo 4 M telescopes
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1990AJ.....99..965M&db_key=AST
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Orbits of 20 visual binaries
Orbital elements of 20 visual binaries have been determined fromobservations in 1984 and 1985. The pairs include 14 Lyn, Mu Vel, IotaLeo, and 77 Cyg. At least eight objects are evolved and two containsubsystems. The binaries are listed along with their elements andephemerides. The observations and residuals are also given. Comments oneach of the objects are presented.
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The chemical evolution of the solar neighborhood. I - A bias-free reduction technique and data sample
The possible ways of measuring the age-metallicity relation for thegalactic disk in the neighborhood of the sun are discussed. It is shownthat the use of a field star sample chosen on the basis of effectivetemperature introduces a bias which results in a monotonic increase inthe metal abundance of the disk with time. However, if theage-metallicity relation for the disk can be shown to satisfy certaincriteria, the bias introduced in such a sample can be neglected: thegalactic disk apparently satisfies the criteria. It is concluded that asample analyzed through the use of uvby and H(beta) photometry inconjunction with a self-consistent set of theoretical isochronesprovides the least biased, most accurate estimate of the age-metallicityrelation for the disk.
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Polarization measurements of 313 nearby stars
The linear polarization of 313 low galactic latitude stars has beenmeasured. With few exceptions all program stars have a spectral typelater than B9 and are within 600 parsec of the sun. 181 stars aresituated at the southern sky and 132 at the northern sky.
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Measures of southern visual double stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976PASP...88...52H&db_key=AST
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MK classification for visual binary components
MK classifications are presented for both components of 208 visualbinaries, most of which appear in the Third Catalogue of Orbits ofVisual Binary Stars (Finsen and Worley 1970) and which have onlycomposite MK spectral types and visual-magnitude differences. Comparisonbetween the results obtained and the several individually observed orpreviously inferred component types suggest that an accuracy of plus orminus 2 to 3 spectral subtypes may be expected for both unevolved pairsand evolved pairs; an accuracy of plus or minus 0.5 to 1.0 luminosityclasses is expected for evolved pairs.
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Visual double stars measured at Las Campanas Observatory, Chile.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975PASP...87..945H&db_key=AST
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Multicolor photometry of metallic-line stars. III. A photometric catalogue
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974RMxAA...1..175M&db_key=AST
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Measures of Southern Visual Double Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974PASP...86..907H&db_key=AST
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Micrometer measures of 401 double stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972AJ.....77..878W&db_key=AST
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Katalog von 121 Doppelsternbahnen.
Not Available
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INHABITED SKY
