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HD 87436


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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.

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

Ca II H and K Filter Photometry on the UVBY System. II. The Catalog of Observations
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995AJ....109.2828T&db_key=AST

Liste des étoiles Ap et Am dans les amas ouverts (édition révisée)
Not Available

The calibration of Stromgren photometry for A, F and early G supergiants. III - The A and early F supergiants
This paper deals with the calibration of Stromgren photometry for the Aand early F supergiants. We derive a gravity parameter which can be usedto separate photometrically supergiants of different luminosity classes.It is used in conjunction to derive a simple calibration which gives theintrinsic color, of the supergiant. This calibration is tested andcompared with other reddening estimates for A and F supergiants in theliterature. Finally, we derive a semiempirical effective temperaturecalibration for the A and F supergiants.

The calibration of the Stromgren photometric system for A, F and early G supergiants. I - The observational data
An empirical calibration of the Stromgren uvby-beta photometric systemfor the A, F, and early G supergiants is being derived. This paperexplains the observational program and the photometric reductiontechniques used and presents a catalog of new Stromgren photometry forover 600 A, F, and G supergiants.

Liste des étoiles Ap et Am dans les amas ouverts (Edition révisée)
Not Available

Walraven photometry of nearby southern OB associations
Homogeneous Walraven (VBLUW) photometry is presented for 5260 stars inthe regions of five nearby southern OB associations: Scorpio Centaurus(Sco OB2), Orion OB1, Canis Major OB1, Monoceros OB1, and Scutum OB2.Derived V and (B - V) in the Johnson system are included.

The late A-type stars - Refined MK classification, confrontation with Stromgren photometry, and the effects of rotation
The MK spectral classification for late A-type stars is refined and theeffects of rotation of spectral classification and uvby(beta) photometryfor these stars are examined. It is found that, for A3 stars, the4417/4481 A wavelength ratio produces results that are inconsistent withthe Stark broadening of the H lines. It is suggested that this ratio isnot useful as a luminosity criterion at any spectral type.Self-consistent sequences of narrow- and broadline standards areestablished. The results of the refined classification system arecompared with Stromgren photometry, showing a set of low-v sin i A-typestars with anomalously large delta(c1) indices for theirluminosity types. It is proposed that these stars are rapid rotatorsseen at fairly low inclination angles.

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.

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.

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.

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

New AP Stars in NGC 3114
Not Available

Photometric Observations of NGC 3114
Not Available

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Gözlemler ve gökölçümü verileri

Takýmyýldýz:Karina
Sað Açýklýk:10h02m59.90s
Yükselim:-60°10'43.0"
Görünürdeki Parlaklýk:6.19
Uzaklýk:990.099 parsek
özdevim Sað Açýklýk:-8.1
özdevim Yükselim:5.1
B-T magnitude:6.382
V-T magnitude:6.198

Kataloglar ve belirtme:
Özgün isimleri   (Edit)
HD 1989HD 87436
TYCHO-2 2000TYC 8943-1105-1
USNO-A2.0USNO-A2 0225-07339744
BSC 1991HR 3966
HIPHIP 49233

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