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HD 51480


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Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available

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.

Circular Polarization of Starlight
Of the 7500 stars cited in the Catalog of starlight polarization, thosewhich satisfy the condition P obs % and A V 0m.5 are selected. It ispresumed that the selected stars (n=216) have circularly polarizedlight.

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.

New periodic variables from the Hipparcos epoch photometry
Two selection statistics are used to extract new candidate periodicvariables from the epoch photometry of the Hipparcos catalogue. Theprimary selection criterion is a signal-to-noise ratio. The dependenceof this statistic on the number of observations is calibrated usingabout 30000 randomly permuted Hipparcos data sets. A significance levelof 0.1 per cent is used to extract a first batch of candidate variables.The second criterion requires that the optimal frequency be unaffectedif the data are de-trended by low-order polynomials. We find 2675 newcandidate periodic variables, of which the majority (2082) are from theHipparcos`unsolved' variables. Potential problems with theinterpretation of the data (e.g. aliasing) are discussed.

Gas—Dust Shells around Some Early-Type Stars with an IR Excess (of Emission)
The results of an investigation of IR (IRAS) observations of 58O—B—A—F stars of different luminosity classes, whichare mainly members of various associations, are presented. The colorindices of these stars are determined and two-color diagrams areconstructed. The emission excesses at 12 and 25 mm (E 12 and E 25) arealso compared with the absorption A1640 of UV radiation. It is concludedthat 24 stars (of the 58 investigated) are disk systems of the Vegatype, to which Vega = N 53 also belongs. Eight known stars of the Vegatype are also given in the figures for comparison. The remaining 34stars may have gas—dust shells and/or shell—disks. The IRemission excesses of the 34 investigated stars and 11 comparison stars(eight of them are Be-Ae stars) are evidently due both to thermalemission from grains and to the emission from free—freetransitions of electrons in the gas—dust shells of these stars.

Statistical analysis of intrinsic polarization, IR excess and projected rotational velocity distributions of classical Be stars
We present the results of statistical analyses of a sample of 627 Bestars. The parameters of intrinsic polarization (p*),projected rotational velocity (v sin i), and near IR excesses have beeninvestigated. The values of p* have been estimated for a muchlarger and more representative sample of Be stars (~490 objects) thanpreviously. We have confirmed that most Be stars of early spectral typehave statistically larger values of polarization and IR excesses incomparison with the late spectral type stars. It is found that thedistributions of p* diverge considerably for the differentspectral subgroups. In contrast to late spectral types (B5-B9.5), thedistribution of p* for B0-B2 stars does not peak at the valuep*=0%. Statistically significant differences in the meanprojected rotational velocities (/line{vsin i}) are found for differentspectral subgroups of Be stars in the sense that late spectral typestars (V luminosity class) generally rotate faster than early types, inagreement with previously published results. This behaviour is, however,not obvious for the III-IV luminosity class stars. Nevertheless, thecalculated values of the ratio vt/vc of the truerotational velocity, vt, to the critical velocity forbreak-up, vc, is larger for late spectral type stars of allluminosity classes. Thus, late spectral type stars appear to rotatecloser to their break-up rotational velocity. The distribution of nearIR excesses for early spectral subgroups is bi-modal, the position ofthe second peak displaying a maximum value E(V-L)~ 1 . m 3for O-B1.5 stars, decreasing to E(V-L)~0. m8 for intermediatespectral types (B3-B5). It is shown that bi-modality disappears for latespectral types (B6-B9.5). No correlations were found betweenp* and near IR excesses and between E(V-L) and vsin i for thedifferent subgroups of Be stars. In contrast to near IR excesses, arelation between p* and far IR excesses at 12 mu m is clearlyseen. A clear relation between p* and vsin i (as well asbetween p* and /line{vsin i}/vc) is found by thefact that plots of these parameters are bounded by a ``triangular"distribution of p*: vsin i, with a decrease of p*towards very small and very large vsin i (and /line{vsini}/vc) values. The latter behaviour can be understood in thecontext of a larger oblateness of circumstellar disks for the stars witha rapid rotation. From the analysis of correlations between differentobservational parameters we conclude that circumstellar envelopes forthe majority of Be stars are optically thin disks with the range of thehalf-opening angle of 10degr

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

Dust shells around certain early-type stars with emission lines.
Not Available

UBV beta Database for Case-Hamburg Northern and Southern Luminous Stars
A database of photoelectric UBV beta photometry for stars listed in theCase-Hamburg northern and southern Milky Way luminous stars surveys hasbeen compiled from the original research literature. Consisting of over16,000 observations of some 7300 stars from over 500 sources, thisdatabase constitutes the most complete compilation of such photometryavailable for intrinsically luminous stars around the Galactic plane.Over 5000 stars listed in the Case-Hamburg surveys still lackfundamental photometric data.

A Radial Velocity Database for Stephenson-Sanduleak Southern Luminous Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....113..823R&db_key=AST

A Search for Pulsar Companions to OB Runaway Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996ApJ...461..357S&db_key=AST

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.

A spectroscopic database for Stephenson-Sanduleak Southern Luminous Stars
A database of published spectral classifications for objects in theStepenson-Sanduleak Luminous Stars in the Southern Milky Way catalog hasbeen compiled from the literature. A total of 6182 classifications for2562 stars from 139 sources are incorporated.

Radio continuum emission from stars: a catalogue update.
An updated version of my catalogue of radio stars is presented. Somestatistics and availability are discussed.

The Peculiar Interacting Binary V644 Monocerotis
Spectroscopic techniques have been used to model the V644 Mon (HD 51840)system, a single-line binary consisting of an early-type main sequence(B1 V) star and a mass-losing late-type supergiant (K0 I-II). Highresolution CCD spectra of V644 Mon were obtained at the Ritter andMcMath-Pierce Observatories between November 1993 and April 1994. Anorbital solution yields a period of 120.6+/-0.1 days and semi-amplitudefor the K star of 60.4+/-1.4 km/s. A v sin i \ for the K star of 20+/-5km/s is measured, and its bolometric magnitude and temperature suggest aradius near 80R_sun. From these data an inclination near 40 degrees isestimated for the system. Photometric evidence for ellipsoidalvariations suggests that the K star is tidally deformed and transferringmatter through the inner Lagrangian point onto and around the B star. Aconsistent model yields masses of 4M_sun \ and 13M_sun \ for the K and Bstars, respectively, the former having lost as much as 10M_sun. Thismaterial is most likely responsible for the shell/wind iron peakabsorption features observed by IUE against the UV continuum of the Bstar. Optical shell/wind lines are also observed at H? , He I lambda5875, Na I D, and Ca II K.

Radio observations of peculiar emission-line Algol binary stars
Twelve peculiar emission-line Algol (PELA) binaries were observed at cmwavelengths. Six of these objects, WW And (tentative), KX And, AM Aur,V644 Mon, DN Ori, and AY Per were detected at the 100 to 400 micro-Jylevel, corresponding to luminosity densities of order 10 exp 17erg/s/Hz. These luminosity densities, combined with nearly flat cmspectra and high brightness temperatures, are consistent with thenonthermal gyrosynchrotron radiation model proposed as the result ofobservations from the previous PELA survey. Also, the star V367 Cyg wasreobserved at thirteen different orbital phases; no variability wasfound within the errors. V367 Cyg's lack of variability andwell-determined average spectral index, however, imply the possibilityof a different emission mechanism, thermal bremsstrahlung, although thenonthermal model cannot be entirely ruled out. The characteristicbrightness temperature of thermal bremsstrahlung is only about 10,000 K,which means that the radius of the emission region would have to be muchlarger than previously assumed, about 10 AU. Suggestions for furtherobservations of all previously observed PELAS are presented in order todetermine the correct emission mechanism.

Stellar associations in the region of CMa
Forty-three early-type stars brighter than 9 mag at 1640 A were observedin the region of CMa with the Glazar Space Telescope. The observed starsare shown to compose three groups situated at distances of 320, 570, and1100 pc. The first two groups are B-associations, and the third is anO-association. It is concluded that the dust matter situated atdistances up to 1000 pc yields an interstellar extinction parameter of0.7 mag at 1640 A.

Identification of 106 new infrared carbon stars in the IRAS Point Source Catalog - Near-infrared photometry and their space distribution in the galaxy
A method based solely on IR colors - the combination of near-IR and IRAScolors - is used to identify 106 new IR carbon stars (IRCS). It is shownthat the proportion of IRCS in a region of the IRAS two-color diagrampreviously thought to contain the largest concentration of such stars isnot as large as expected for the faintest objects. A local spatialnumber density of about 12 IRCS/sq kpc is estimated. It is shown to beuniform within 5 to 11 kpc from the galactic center. The local ratio ofIRCS to optical carbon stars is found to be about 35 percent. A totalrestitution rate of about 10 to the -4 solar masses/yr/sq kpc isderived. The efficiency of the combination of near and mid-IR photometryfor the study of AGB stars is confirmed.

A catalogue of radii of Be star line emitting regions
A bibliographic catalog of the radii of the line-emitting regions aroundBe stars is presented. The table also provides the separation of theemission peaks, the wavelength of the line used, observing date, and theV sin i value given by the author.

SAO stars with infrared excess in the IRAS Point Source Catalog
We have undertaken a search for SAO stars with infrared excess in theIRAS Point Source Catalog. In contrast to previous searches, the entireIRAS (12)-(25)-(60) color-color diagram was used. This selection yieldeda sample of 462 stars, of which a significant number are stars withcircumstellar material. The stars selected can be identified aspre-main-sequence stars, Be stars, protoplanetary systems, post-AGBstars, etc. A number of objects are (visual) binary stars.Characteristic temperatures and IR excesses are calculated and theirrelations to spectral type are investigated.

Radio Emission From Peculiar Emission-Line Algol Binaries
Not Available

UBV photometry of OB+ stars in the southern Milky Way
One thousand two hundred and twenty six new observations are combinedwith previously published results of the author to yield an internalyconsistent set of magnitudes and colors on the international UBV systemfor 666 stars classified as OB+ in the Stephenson-Sanduleak OB starsurvey. The U - B, B - V diagram indicates that these stars consistprimarily of O-type stars and early B-type supergiants, reddened by upto E(B - V) = 2.1 mag.

Photometry of HD 51480 = V644 Monocerotis - A Be binary system
Four years of photometry of the composite Be + K binary system HD 51480= V644 Mon is presented. The star is found to be irregularly variable.Analysis of two coude spectra of the H-alpha region reveals a continuingstrong P Cygni profile for H-alpha which is variable in a minor fashion.

Optical observations of the unusual interacting binary V644 Monocerotis (HD 51480)
New optical spectroscopic and UBV photometric observations of the brightBe/shell star V644 Mon (HD 51480) are presented. The object, which hasbeen described as an interacting binary system, exhibits strong,variable Balmer emission as well as numerous metallic emission featuresin the blue. No signs of absorption features due to any late-typecompanion are seen at wavelengths below 6500 A.

ICCD speckle observations of binary stars. III - A survey for duplicity among high-velocity stars
An analysis of speckle interferometry data for 182 stars has resulted inthe detection of 10 binaries, four of which are newly resolved systems.After correcting for selection effects, the data are found to becompatible with a total frequency for high-velocity long-period doubleswhich is as large as that for low-velocity stars. Based on spectroscopicparallaxes and visual magnitudes, these binaries are found to be within100 pc of the sun, with eight having linear separations of less than 20AU. Four of the binaries are determined to have periods of less than 20yr.

The Peculiar Be Star V644 Mon - HD 51480 as an Interacting Binary
Not Available

Effective temperatures, radii, and luminosities of O emission, Be and AE stars
Dereddened fluxes, together with the ultraviolet measurements ofThompson et al. (1978), have been compared with those of Kurucz's (1979)model atmospheres to derive effective temperatures of some O-emission,Be and Ae stars. With the measured monochromatic fluxes, their angulardiameters and luminosities were determined. It is found that themajority of the stars are cooler than the Zero-Age Main Sequence (ZAMS),suggesting that they are slightly more evolved than ZAMS stars.

Catalog of O-B stars observed with Tokyo Meridian Circle
A catalog of the O-B stars, selected from 'Blaauw-Parenago' list andRubin's catalog, has been compiled on the FK4 system by the observationsmade with Gautier 8-inch Meridian Circle at the Tokyo AstronomicalObservatory during the period, 1971 to 1979. It contains 1059 stars andwas compiled for the future establishment of high precision propermotions of O-B stars.

Optical and infrared photometry of southern early-type shell stars and pre-main-sequence variables
A catalogue of optical and infrared photometry is presented covering theepoch 1980 to 1984 for a sample of 53 pre-main-sequence stars and otheremission-line objects, mainly of early spectral type. The JHKL data aregenerally simultaneous with optical photometry in either the UBVRI orStromgren uvby systems, and the H beta index is used as a photometricmonitor of spectrum variability. This catalogue will form a valuabledata set for future studies of the nature and origin of variability inthis class of object.

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Observation and Astrometry data

Constellation:いっかくじゅう座
Right ascension:06h57m09.38s
Declination:-10°49'28.1"
Apparent magnitude:6.942
Distance:10000000 parsecs
Proper motion RA:-1.6
Proper motion Dec:-0.5
B-T magnitude:7.279
V-T magnitude:6.97

Catalogs and designations:
Proper Names
HD 1989HD 51480
TYCHO-2 2000TYC 5384-2488-1
USNO-A2.0USNO-A2 0750-03137386
HIPHIP 33436

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