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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Interstellar polarization at high galactic latitudes from distant stars. 2: First results for Z less than or equal to 600 PC
We present the first results from our Crimean-Tuorla program forpolarimetry of distant stars at high galactic latitudes. The availableobservations reveal a clear increase in the interstellar linearpolarization of A and F stars, up to Z approximately equals 600 pc whereone reaches PV approximately equals 0.25%. This means anaverage AB greater than or equal to 0.11 mag over thenorthern polar cap for the diffuse component of the interstellarextinction that we are probing. There is no clear indication in the datathat the asymptotic level of PV has been reached, and withfuture observations above Z = 600 pc we shall investigate this question.The trend found is in agreement with the stellar reddening analysis byTeerikorpi (1990). The directions of the plane of vibration are inagreement with Markkanen's (1979) analysis of closer (Z less than 200pc) stars in his 'Area II'. Outside of this area we define two sectors Band C which encompass the Local Spiral Arm and had little stars inprevious investigations. Here the polarization vectors deviate stronglyfrom those in Markkanen's Area II, where one is probably looking at aninterarm region, close to the edge of the Local Spiral Arm. Ourmeasurements indicate for B and C average polarization vectorsconsistent with the direction l approximately equals 110 deg obtained byother authors for the magnetic field in the Local Spiral Arm using therotation measure method.
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Lithium in high velocity A and F stars: Constraints on the blue straggler phenomenon
We have determined equivalent widths for a number of atomic lines,including the lambda 6707 resonance doublet of Li, from spectra of asample of candidate early-type high-velocity stars (including a numberof blue straggler candidates) and low-velocity comparison stars. We findthat the high-velocity candidates can be divided into three distinctgroups: (1) stars with low abundances both of Li and of metals ingeneral; (2) stars with low abundances of Li but only slightdeficiencies of the other metals; and (3) stars with nearly normalamounts of both Li and other metals. We tentatively identify thesegroups as (1) halo and thick-disk blue stragglers; (2) old, thinnishdisk blue stragglers; and (3) nearly normal Population l stars whichprobably lie in the tail of the usual Pop. l velocity distribution. Thekinematic properties of the three groups are consistent with thisinterpretation. Li is a fragile element which is easily destroyed in thehot interiors of main-sequence stars, and has previously been shown tobe depleted in the atmospheres of blue stragglers in the open clusterM67. Our results on objects that we have identified in this paper asold, halo or thick disk, field blue stragglers suggest that lithiumdepletion is a general property of blue stragglers; this argues thatlarge scale mixing must be a part of any mechanism that produces bluestragglers. Our observations of low lithium abundances in a number ofmetal-normal, high-velocity, A stars, suggest that the high-latitude Astars observed by Rodgers an d collaborators are probably not producedin the collison of a Magellanic Cloud-like object with the Galactic diskin the past few Gyr. A more likely hypothesis (that is consistent withour lithium abundances) is that the high latitude, normal gravity,metal-rich, A star population consists primarily of blue stragglers.These data also have allowed a redetermination of the relationshipbetween the Stromgren metallicity index delta mo and (M/H)for low-metallicity objects.
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Early type high-velocity stars in the solar neighborhood. IV - Four-color and H-beta photometry
Results are presented from photometric obaservations in the Stromgrenuvby four-color and H-beta systems of early-type high-velocity stars inthe solar neighborhood. Several types of photometrically peculiar starsare selected on the basis of their Stromgren indices and areprovisionally identified as peculiar A stars, field horizontal-branchstars, metal-poor stars near the Population II and old-disk turnoffs,metal-poor blue stragglers, or metallic-line A stars. Numerousphotometrically normal stars were also found.
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Miscellaneous spectroscopic notes
Results of slit-spectrograph observations are reported for approximately260 stars. The data presented range from recognition of many new Ap, Am,and other unusual stars to H-alpha observations of early-typesupergiants and Be stars. The material discussed was obtained over thepast 40 years at a number of U.S. observatories and at the DominionAstrophysical Observatory in Victoria, B.C.
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Common proper motion stars in the AGK 3
A search was made of common-proper-motion (CPM) systems among AGK 3stars. The selection of physical systems was based upon the ratiobetween the angular separation (rho) and the proper motion (mu); the CPMstars found are presented in two tables. Table I lists systems withrho/mu less than 1000 years. It contains 326 entries, and the proportionof optical pairs is estimated to be 1 percent. Table II lists systemswith rho/mu in the range 1000 to 3500 years; it contains 113 systems,but only 60 percent of them are physical. Nevertheless, these systemsoften have separations larger than 10,000 AU and are the mostinteresting for the study of the tail of the distribution function ofthe semimajor axes.
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Early-type high-velocity stars in the solar neighborhood. III - Radial velocities, rotation indices, and line-strength indices for southern candidates
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983AJ.....88.1349S&db_key=AST
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Further Studies of A-Stars and F-Stars in the Region of the North Galactic Pole - Part Four - a Catalogue of Uvbyr Photometry and Derived Quantities
Not Available
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Further Studies of A-Stars and F-Stars in the Region of the North Galactic Pole - Part Three - a Catalogue of Star Names and Positions
Not Available
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Early-type high-velocity stars in the solar neighborhood. I - List of candidates
Suspected nearby high-velocity stars of spectral types B and A areidentified by their proper motions, which are generally too small forthe stars to have been included in previous catalogs of high-velocitystars. The same selection process is then extended to spectral type Fstars, in order to both provide a companion sample and investigatewhether the hypothetical high-velocity, metal-rich population continuesto later spectral types. Of the presented list of 371 stars withconfirmed proper motions, 168 are of A and B spectral types. Photometricand spectroscopic observations of these stars are required to eliminatethose with misclassified spectra and convert proper motions into spacevelocities. The identification of type of stars is important forunderstanding apparent exceptions to the correlation between stellarages, metal abundances, and kinematic properties.
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UVBY Bet study of A-and F-type visual binaries. II.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978AJ.....83.1646M&db_key=AST
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Studies of A and F stars in the region of the North galactic pole-II. uvby β photometry
Not Available
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Studies of A and F stars in the region of the North galactic pole-I. Radial velocities and MK Classifications
Not Available
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Interstellar reddening near the north galactic pole
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972PASP...84..497F&db_key=AST
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The Motions of the A Stars at the North Galactic Pole
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969PASP...81..741E&db_key=AST
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The galactic force law K(z
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969AJ.....74..139P&db_key=AST
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Radial Velocities of A-Type Stars Near the North Galactic Pole
Not Available
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Three-colour photometry of early-type stars near the galactic poles
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963MNRAS.127...83W&db_key=AST
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A list of stars with common proper motions.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1958AJ.....63..246V&db_key=AST
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INHABITED SKY
