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HD 50648


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Hipparcos red stars in the HpV_T2 and V I_C systems
For Hipparcos M, S, and C spectral type stars, we provide calibratedinstantaneous (epoch) Cousins V - I color indices using newly derivedHpV_T2 photometry. Three new sets of ground-based Cousins V I data havebeen obtained for more than 170 carbon and red M giants. These datasetsin combination with the published sources of V I photometry served toobtain the calibration curves linking Hipparcos/Tycho Hp-V_T2 with theCousins V - I index. In total, 321 carbon stars and 4464 M- and S-typestars have new V - I indices. The standard error of the mean V - I isabout 0.1 mag or better down to Hp~9 although it deteriorates rapidly atfainter magnitudes. These V - I indices can be used to verify thepublished Hipparcos V - I color indices. Thus, we have identified ahandful of new cases where, instead of the real target, a random fieldstar has been observed. A considerable fraction of the DMSA/C and DMSA/Vsolutions for red stars appear not to be warranted. Most likely suchspurious solutions may originate from usage of a heavily biased color inthe astrometric processing.Based on observations from the Hipparcos astrometric satellite operatedby the European Space Agency (ESA 1997).}\fnmsep\thanks{Table 7 is onlyavailable 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/qcat?J/A+A/397/997

New Hipparcos variables in the Bright Star Catalogue.
Not Available

Long period variable stars: galactic populations and infrared luminosity calibrations
In this paper HIPPARCOS astrometric and kinematic data are used tocalibrate both infrared luminosities and kinematical parameters of LongPeriod Variable stars (LPVs). Individual absolute K and IRAS 12 and 25luminosities of 800 LPVs are determined and made available in electronicform. The estimated mean kinematics is analyzed in terms of galacticpopulations. LPVs are found to belong to galactic populations rangingfrom the thin disk to the extended disk. An age range and a lower limitof the initial mass is given for stars of each population. A differenceof 1.3 mag in K for the upper limit of the Asymptotic Giant Branch isfound between the disk and old disk galactic populations, confirming itsdependence on the mass in the main sequence. LPVs with a thin envelopeare distinguished using the estimated mean IRAS luminosities. The levelof attraction (in the classification sense) of each group for the usualclassifying parameters of LPVs (variability and spectral types) isexamined. Table only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/374/968 or via ASTRIDdatabase (http://astrid.graal.univ-montp2.fr).

Sinusoidal variables from the Tycho Epoch Photometry Annex
The Tycho Epoch Photometry Annex A, a data base of photometry of morethan 34 000 bright stars, has been searched for periodic variablestars with approximately sinusoidal light curves. Advantage was taken ofspecial properties of the observing programme (photometry in twowavebands, availability of repeated measurements) to use simple butefficient variable selection criteria. Details of 70 strong candidatevariables are presented.

The 74th Special Name-list of Variable Stars
We present the Name-list introducing GCVS names for 3153 variable starsdiscovered by the Hipparcos mission.

Classification and Identification of IRAS Sources with Low-Resolution Spectra
IRAS low-resolution spectra were extracted for 11,224 IRAS sources.These spectra were classified into astrophysical classes, based on thepresence of emission and absorption features and on the shape of thecontinuum. Counterparts of these IRAS sources in existing optical andinfrared catalogs are identified, and their optical spectral types arelisted if they are known. The correlations between thephotospheric/optical and circumstellar/infrared classification arediscussed.

Asymptotic giant branch stars near the sun
Available red and near-infrared photometry and apparent motions of M, S,and C asymptotic giant branch (AGB) stars in the Bright Star Catalogueare tabulated and discussed. It is shown that the red and near infraredindices normally used for late-type stars are interchangeable except forcarbon stars. The M-type giants are variable with visual amplitudegreater than 0.05 mag. The reddening-free parameter m2 from Genevaphotometry is essentially a temperature parameter for M giants, whilethe reddening-free parameter d is a sensitive detector of blue stellarcompanions. The space density of AGB stars near the sun decreases by afactor of 35 in a temperature range 3800 to 3400 K. Two of the S starsnear the sun were found to have nearly equal space motions and may becomembers of the Arcturus group.

Radial velocity monitoring of a sample of barium and S stars using CORAVEL - Towards an evolutionary link between barium and S stars?
The paper presents the preliminary results of a radial velocitymonitoring of a sample of 27 southern Ba II and 9 northern S stars,extending over three seasons, and performed with the CORAVELspectrometer. Both samples contained a large number of stars withvariable radial velocities. At least five S stars show velocityvariations originating in orbital motions, while Mira-type pulsations ofsmall amplitude may be a possibility for three more S stars displayingvelocity variations with dispersions in the interval of 1.0-1.5 km/s. Abinary scenario involving mass transfer and accounting for the dualorigin of S stars is suggested.

E. W. Fick Observatory stellar radial velocity measurements. I - 1976-1984
Stellar radial velocity observations made with the large vacuumhigh-dispersion photoelectric radial velocity spectrometer at FickObservatory are reported. This includes nearly 2000 late-type starsobserved during 585 nights. Gradual modifications to this instrumentover its first eight years of operation have reduced the observationalerror for high-quality dip observations to + or - 0.8 km/s.

IRAS catalogues and atlases - Atlas of low-resolution spectra
Plots of all 5425 spectra in the IRAS catalogue of low-resolutionspectra are presented. The catalogue contains the average spectra ofmost IRAS poiont sources with 12 micron flux densities above 10 Jy.

Radial velocities of southern stars obtained with the photoelectric scanner CORAVEL. III - 790 late-type bright stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985A&AS...59...15A&db_key=AST

The radial velocities of 116 southern red stars
Using a photoelectric speedometer based on the radial velocityspectrometer of Griffin (1967), radial velocities of 116 southern redstars, many of them semi-regular variables, were measured. Theinstrument was placed at the Newtonian focus of the 130-inch (4.2-m)camera of the Coude spectrograph of the Mount Stromlo 74-inch (1.88-m)reflector. The stellar spectrum was focused on a mask 50 mm in length,designed to match the spectrum of the M-giant Beta Pegasi. The inversedispersion was 2.5 angstroms per millimeter in the second order. Thewavelength range used (5338-5449 angstroms) was chosen because it isbetween two TiO bands and so suffers less blanketing in M stars. Resultsare tabulated and compared with standard values.

A catalog of selected compact radio sources for the construction of an extragalactic radio/optical reference frame
A catalog of 234 strong compact extragalactic radio sources that displayoptical counterparts is presented. This catalog identifies proposedsources for establishing an almost inertial reference frame againstwhich the motions of the earth, solar system, galactic objects, andspacecraft may be measured. This catalog also defines those sources forwhich precise optical positions should be determined in order to relatethis reference frame with the optical FK 5 fundamental system. Theaccuracy of the radio source positions of these sources is not greaterthan 0.1 arcsec with the majority not greater than 0.01 arcsec. Furtherrefinement to not greater than 0.005 arcsec by future observations isexpected soon.

List of 333 variable, microvariable or suspected variable stars detected in the Geneva photometry
A list is presented of 333 stars, excluded from the GCVS and itssupplements, whose probability of variability ranges from high tocertain. The standard deviations observed in the V magnitude togetherwith the known spectral types, however, only allow speculation as to thetype of variable in question pending supplementary observations whichreveal the individual characteristics of these stars.

Radial velocities of southern HR stars. II
Fick Observatory's second major installment of radial-velocitymeasurements of bright southern stars is presented. This includes 373radial-velocity measurements for 90 stars which were obtained betweenJanuary 1978 and June 1981. Fifteen new possible velocity variables andone new double-line spectroscopic binary (HD 1782) have been detected.Subsequent velocity measurements of stars from the first southern HRstudy (Beavers and Eitter, 1980) found that (1) two stars (HR 0745 andHR 5428), originally classified as possible variables, are actuallyconstant velocity variables, and that (2) HR 0953 is a definite velocityvariable covering a range of at least -1 to +14 km/sec. This study, whencombined with the earlier southern HR observations and those reported byGriffin (1972), result in a total of 280 HR objects with newradial-velocity determinations.

Neue Veraenderliche Sterne am Sudhimmel.
Not Available

Narrow-Band and Broad-Band Photometry of Red Stars. III. Southern Giants
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJ...161..199E&db_key=AST

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관측 및 측정 데이터

별자리:큰개자리
적경:06h53m00.10s
적위:-26°57'27.0"
가시등급:6.4
거리:254.453 파섹
적경상의 고유운동:-7.5
적위상의 고유운동:-65.7
B-T magnitude:8.255
V-T magnitude:6.586

천체목록:
일반명
HD 1989HD 50648
TYCHO-2 2000TYC 6530-1428-1
USNO-A2.0USNO-A2 0600-04268159
BSC 1991HR 2567
HIPHIP 33040

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