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Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
The Catalogue, available at the Centre de Données Stellaires deStrasbourg, consists of 13 573 records concerning the results obtainedfrom different methods for 7778 stars, reported in the literature. Thefollowing data are listed for each star: identifications, apparentmagnitude, spectral type, apparent diameter in arcsec, absolute radiusin solar units, method of determination, reference, remarks. Commentsand statistics obtained from CADARS are given. The Catalogue isavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcar?J/A+A/367/521
| 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
| NGC 2287 - an important intermediate-age open cluster
We have obtained photoelectric UBV photometry for 100 stars, uvby-betaphotometry for 39 stars, and MK spectral types for 80 stars in the fieldof NGC 2287. After combination with data from other sources, severalinteresting cluster properties are apparent. Both the UBV and uvby-betaphotometry point to a small but nonzero reddening, while our spectraltypes confirm previous results indicating a high binary frequency forthe cluster. Based on our spectral and photometric data for the clustermembers with M(V) of between -1 and 3, we find a minimum binaryfrequency of 40 percent and discuss the possibility that the results mayimply a binary frequency closer to 80 percent. The cluster age is foundto be about 2 x 10 exp 8 yr based on both the main-sequence turnoff andthe red giant distribution; the width of the turnup region can probablybe explained by a combination of duplicity and a range in stellarrotation.
| More radial-velocity measurements in young open clusters
Further high resolution radial-velocity measurements are reported in 23young open clusters using the Kitt Peak CCD coude spectrograph on the0.9-m feed telescope. The radial velocities for the cluster stars arederived with the technique of cross correlation. The internal precisionof the velocity measurements is typically 2 km/s for early type stars.From these new data and previously published velocities, the observedstars in two clusters, NGC 663 and NGC 2287, were found to show arelatively small dispersion in the measured mean velocities. Furtherobservations of stars in young clusters will be useful in helping toestablish an early-type-star-velocity standard system.
| 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.
| Age determination of the open cluster NGC 2287 (M41)
Two different methods which take into account the rotation of the memberstars are used to determine the cluster age of NGC 2287 (M41). Thetheoretical Hertzsprung-Russell diagram is first obtained from theobserved color-magnitude diagram. The method based on the turn-off pointon the cluster Main Sequence yields an age of 3.10 x 10 to the 7th yr.By fitting the evolutionary tracks of rotating stars to the clusterHertzsprung-Russell diagram, an age of about 8.00 x 10 to the 7th yr isobtained.
| Radial velocities in the direction of the cluster NGC 2287
Mean radial velocities for 72 stars in the direction of NGC 2287 havebeen determined based on 10 plates obtained with the 40-cm ObjectivePrism of the La Silla ESO. The radial velocities are given in the IAUsystem with an accuracy of + or - 5 km/s. It is found that the peculiarstar HD 49022 is variable and has an amplitude of 70 km/s. The generalvelocity diagram has a maximum at about 22 km/s which may represent amixture of cluster and field stars and an asymmetry at 30 km/s which maybe attributed to binary member stars.
| Membership in the open cluster NGC 2287
The open cluster NGC 2287 is a cluster apparently rich in multiple starsand several other spectroscopically interesting objects. The firstextended proper-motion membership survey of the cluster is reported. UBVphotometry of 146 proper-motion stars is also included and compared toearlier data. Color-magnitude and two-color diagrams are presented. Theproper-motion-based membership probabilities indicate that most of thespectroscopic binaries are members of the cluster, as are the threeHg-Mn stars, and at least four of the K giants. The bright He-weak starHD 49333 does not appear to be a cluster member. A ZAMS fit to acolor-magnitude diagram of the most likely members gives a distancemodulus of (m - M) = 9.15.
| Axial rotation in NGC 2287
Axial and rotational velocities of the members of the open cluster NGC2287 are measured. The average rotation of the cluster is compared withthe average rotation of field stars of the same types; it is found thatNGC 2287 rotates at a slower rate than field stars. This result isdiscussed in terms of the correlation among the rotation, binarity, andpeculiarity among members of open clusters.
| Positions of stars in regions of 14 southern galactic clusters
Positions have been obtained for a total of 3487 stars scattered over 14regions that are centered on each of the southern galactic clusters NGC1981, 2287, 2437, 2451, 2516, 2546, 2547, 2548, 3114, 3532, IC 2391,2395, 2602, and Truempler 10. A frame of reference has been establishedfor each region using ESO Schmidt plates centered on the clusters, witheach plate containing 20-35 measurable Perth 70 stars that are used fordetermining the positions of 200-400 fainter stars within a centralfield of 25 min of arc radius (covering the corresponding 1.5-m plates).
| The region of NGC 2287 and CR 121
Intermediate band and H-beta observations of 135 stars in the regions ofthe clusters NGC 2287 and Cr 121 are discussed, and a luminositycalibration of photometric parameters for late G- to early K-type brightgiants and supergiants is introduced. Results indicate that NGC 2287 isat a distance of 740 pc, very little reddened, 100-million years old,and contains three or four G8-K2 bright giants and supergiants and ablue straggler. Cr 121 is 1.17 kpc distant, very little reddened, 1.5million years old and an extension of CMa OB1. Cr 121 contains a nearerconcentration of stars at the same distance as NGC 2287, and theassociation appears to be the same age as CMa OB1, although presequencestars may exist. Intermingling of stars in CMa OB2 and NGC 2287 is alsoconsidered possible, and a test of the calibration of two methods ofluminosity determination of early A-type stars using photometricparameters shows them to be entirely consistent.
| Spectral morphology in the open cluster NGC 2287
Spectral classifications in NGC 2287 have revealed the presence of anHe-weak star, three Hg-Mn stars, one star with a weak K line, one coolAp star and one star with a composite spectrum. Spectroscopic evidencedetermined eight double-line binaries as well as five suspecteddouble-line binaries.
| Mulitcolor Photometry of the Open Cluster NGC 2287
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978A&AS...34..241F&db_key=AST
| Measurements of polarization and colour of stars in the galactic clusters NGC 2244 and NGC 2287
Not Available
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Pozíciós és asztrometriai adatok
| Csillagkép: | Nagy Kutya |
| Rektaszcenzió: | 06h46m14.94s |
| Deklináció: | -20°48'17.8" |
| Vizuális fényesség: | 8.397 |
| Távolság: | 332.226 parszek |
| RA sajátmozgás: | -5.7 |
| Dec sajátmozgás: | -1.4 |
| B-T magnitude: | 8.362 |
| V-T magnitude: | 8.395 |
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