New Estimates of the Solar-Neighborhood Massive Star Birthrate and the Galactic Supernova Rate
The birthrate of stars of masses >=10 Msolar is estimatedfrom a sample of just over 400 O3-B2 dwarfs within 1.5 kpc of the Sunand the result extrapolated to estimate the Galactic supernova ratecontributed by such stars. The solar-neighborhood Galactic-plane massivestar birthrate is estimated at ~176 stars kpc-3Myr-1. On the basis of a model in which the Galactic stellardensity distribution comprises a ``disk+central hole'' like that of thedust infrared emission (as proposed by Drimmel and Spergel), theGalactic supernova rate is estimated at probably not less than ~1 normore than ~2 per century and the number of O3-B2 dwarfs within the solarcircle at ~200,000.
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Catalog of Galactic OB Stars
An all-sky catalog of Galactic OB stars has been created by extendingthe Case-Hamburg Galactic plane luminous-stars surveys to include 5500additional objects drawn from the literature. This work brings the totalnumber of known or reasonably suspected OB stars to over 16,000.Companion databases of UBVβ photometry and MK classifications forthese objects include nearly 30,000 and 20,000 entries, respectively.
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Radial Velocities and Kinematic Membership in the Open Cluster NGC 3114
Echelle spectroscopic observations for 30 bright stars in the field ofthe sparse open cluster NGC 3114 are presented. The sample includesmain-sequence stars, yellow and red giants, and blue stragglercandidates. Radial velocities are derived by cross-correlations usinghigh signal-to-noise ratio standard spectra as templates. The clustermean velocity is well defined from eight giants and severalmain-sequence stars whose average is =-3.52+/-0.25 kms-1. The membership probabilities of the observed stars arecomputed on the basis of the velocity distributions of the cluster andfield stars, and the expected percentage of contamination at eachposition. We classified 19 cluster members and 10 nonmembers; theremaining star is a known spectroscopic binary for which no membershipprobability was assigned. Among the members, there is a bright yellowgiant, seven red giants, and four blue straggler candidates, althoughthey should be considered as turn-off stars. The location of two of themin the color-magnitude diagram (slightly blueward of the turn-off) canbe explained by their low rotational velocities. No velocity variationswere detected in the 16 stars measured more than once, which indicatesthat NGC 3114 possess an abnormally low binary frequency. From spectraltypes of cluster members, a distance modulus (V-Mv)=9.8+/-0.2mag and a reddening E(B-V)=0.07+/-0.01 mag are derived. The cluster ageis estimated to be 1.6×108 yr. The observationspresented here were obtained at the Complejo Astronómico ElLeoncito (CASLEO), which is operated under agreement between the ConsejoNacional de Investigaciones Científicas y Técnicas de laRepública Argentina (CONICET) and the National Universities of LaPlata, Córdoba and San Juan.
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Absolute proper motions of open clusters. I. Observational data
Mean proper motions and parallaxes of 205 open clusters were determinedfrom their member stars found in the Hipparcos Catalogue. 360 clusterswere searched for possible members, excluding nearby clusters withdistances D < 200 pc. Members were selected using ground basedinformation (photometry, radial velocity, proper motion, distance fromthe cluster centre) and information provided by Hipparcos (propermotion, parallax). Altogether 630 certain and 100 possible members werefound. A comparison of the Hipparcos parallaxes with photometricdistances of open clusters shows good agreement. The Hipparcos dataconfirm or reject the membership of several Cepheids in the studiedclusters. Tables 1 and 2 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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Catalogue of blue stragglers in open clusters.
An extensive survey of blue straggler candidates in galactic openclusters of both hemispheres is presented. The blue stragglers wereselected considering their positions in the cluster colour-magnitudediagrams.They were categorized according to the accuracy of thephotometric measurements and membership probabilities. An amount of 959blue straggler candidates in 390 open clusters of all ages wereidentified and classified. A set of basic data is given for everycluster and blue straggler. The information is arranged in the form of acatalogue. Blue stragglers are found in clusters of all ages. Thepercentage of clusters with blue stragglers generally grows with age andrichness of the clusters. The mean ratio of the number of bluestragglers to the number of cluster main sequence stars is approximatelyconstant up to a cluster age of about 10^8.6^ yr and rises for olderclusters. In general, the blue stragglers show a remarkable degree ofcentral concentration.
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Photometry of F-K type bright giants and supergiants. 3: The luminosity, reddening, and heavy element abundance of GK stars
The reddening, luminosity, and heavy element abundance of 250 brightgiants and supergiants of type GK are discussed on the basis of 4 color,DDO, RI, and Geneva photometry Bright giants of type GK with age greaterthan 5 x 108 yr, and of type G0/3 with age greater than 2 x108 yr, are very scarce in the solar neighborhood. The medianspace motion vectors of the bright giants and supergiants with welldetermined space motions are (U, V, W) = (+10.6, -13.2, -7.7) +/- (12.3,8.8, 8.8) km/s. The M1 index for 4 color photometry, whencorrected for luminosity (gravity) effects, is sensitive to heavyelement abundance of the GK stars but may not be reliable for those oftype G0/3. The available spectroscopic determinations of (Fe/H) givemixed results with the two largest samples being internally consistentbut with a large zero-point difference. There is a similar zero-pointshift in the peak frequency of the photometrically determined values ofP(Fe/H) for the F type and for the GK type stars. There is littleevidence for an appreciable galactic, radial gradient in the P(Fe/H)values. A previously noted correlation of the heavy element abundanceindex, delta M1, with the amplitude defect in the B lightcurves of Cepheids, FB, and interpretation of the(PLFB) relation as a (PL(Fe/H)) relation needs furtherinvestigation in light of the apparent sensitivity of M1 toFe/H for the F stars (the domain of the Cepheids with P less than 10 d)and lack of this sensitivity for the G0/3 star (domain of the Cepheidswith P greater than 10 d).
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Liste des étoiles Ap et Am dans les amas ouverts (édition révisée)
Not Available
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Liste des étoiles Ap et Am dans les amas ouverts (Edition révisée)
Not Available
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Catalog of AP and AM stars in open clusters
The previous results of Raab (1922), Markarian (1951), and Collinder(1931) have been used to catalog Ap and Am stars that are in the fieldof open clusters. Tabular data are presented for the clusterdesignation, the HD or HDE number, the right ascension (1900), thedeclination (1900), and the magnitude. Also listed are the spectraltypes and, for certain stars, the probability of cluster membership.
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Photoelectric search for CP2-stars in open clusters. XIII - NGC 3114 and IC 2602
Delta-a photometric observations of two open clusters, obtained usingthe 50-cm and 1-m telescopes at ESO during 1981-1984, are reported. Thedata are presented in extensive tables and graphs and brieflycharacterized. Of the 168 stars measured, eight (six in NGC 3114 and twoin IC 2602) are identified as chemically peculiar upper-main-sequenceobjects with magnetic fields. These hot CP2 stars are found to beblueshifted relative to the cluster main sequences on the V/(b-y)diagrams.
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Stromgren photometry of open clusters. IV - NGC3114 and additional measurements for IC2602
Stromgren photometry of 122 B- and A-type stars in the southern opencluster NGC3114 up to V = 12.mag is presented. The membership of theobserved stars is discussed; a mean reddening of E(b-y) = 0.043 for thecluster is estimated; and the behavior of CP stars in the color diagramsis investigated. Furthermore, additional measurements for 16 stars inthe cluster IC2602 are given, and the membership of these stars isexamined.
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Chemically peculiar stars in open clusters. I - The catalog
The largest existing compilation is presented of Ap and Am open clusterstars. The catalog contains information on 381 chemically peculiar (CP)stars of the upper main sequence in 79 open clusters. The catalog iscomposed of the following tables: (1) the main body, which lists CP (orsuspected CP) stars which are kinematical (or suspected kinematical)members of open clusters; (2) the list of CP (or suspected CP) starssometimes numbered among cluster members but which are actuallykinematical nonmembers; (3) the list of stars sometimes designated as'peculiar' but, in fact, probably not CP; (4) references for numberingsystems of cluster stars; (5) references for membership; and (6)references for spectral and/or peculiarity types.
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Intermediate Band Photometry of the Open Cluster NGC3114
Abstract image available at:http://adsabs.harvard.edu/abs/1982PASP...94..232S
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Radial Velocities of the Mass of NGC3114 Measured on the Objective-Prism of the 40-CM ESO
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1981A&AS...44..101A&db_key=AST
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Relative radial velocities from objective prism spectra in the region of nine southern open star clusters and a star field at Eta Carinae
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980A&AS...41..245G&db_key=AST
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On the existence of companions to L Carinae and its color excess
Fernie suggested that nine early type stars in the vicinity of the 36day Cepheid l Carinae might form a physical group. Four color and H-betaphotometry was obtained to test this suggestion. The distances of thesestars and their ages range widely indicating that all are field starsand cannot be used to estimate the distance of the Cepheid. Thereddening in the field is discussed and it is concluded that l Car isconsiderably redder than other Cepheids of similar period and indicatesthat at high luminosity the Cepheid strip extends further to the redthan has been supposed.
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Classification of intrinsic variables. VI - The long-period Cepheids
A large number of UBV and RI observations of long-period very young diskCepheids and halo Cepheids are examined. The sample includes l Carinae,b Carinae, and RS Puppis from the Galaxy, 10 SMC Cepheids, 11 LMCCepheids, and giants and subgiants in M2, M10, M5 and Omega Centauri.From the data it emerges that the stellar associations to which it hadbeen thought that 1 Car and RS Pup belonged do not exist. The reddeningof Galactic Cepheids is less than usually supposed. The LMC and GalacticCepheids may be very similar. The SMC long-period Cepheids probably haveslightly lower metal abundance than LMC and Galactic Cepheids and almostcertainly are hotter at a given period. Halo Cepheids with periodslonger than about 30 days are of the same luminosity, M(V) = -3.2 mag,if M(V) = +0.6 mag for the very short period variables.
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NGC 3114 : another open cluster possibly rich in peculiar stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975AJ.....80..807L&db_key=AST
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New AP Stars in NGC 3114
Not Available
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Photometric Observations of NGC 3114
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Not Available
Not Available
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INHABITED SKY
