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Rotation curve of the Galactic outer disk derived from radial velocities and UCAC3 proper motions of carbon stars
The availability of astrometric data and radial velocities of carbonstars near the Galactic plane enables us to investigate the kinematicsof the Milky Way, especially the rotation curve. The recently publishedThird U. S. Naval Observatory CCD Astrograph Catalog (UCAC3) providesthe opportunity to test this problem using three-dimensional velocity inorder to obtain more reliable rotation curves. We intend to study theGalactic rotation curve up to 15 kpc using the radial velocities andproper motions of carbon stars. The motivation for using UCAC3 is toprovide high precision proper motions which have hardly been used indetermining the rotation velocity of tracers. Seventy-four carbon starsand carbon-rich Mira variables toward the anti-center direction (90°< ell < 270°, |b| < 6°) are picked up from theliterature then matched with UCAC3 carbon star candidates to obtaintheir proper motions. A rigorous geometrical method is employed tocompute the rotation velocity of each object. Taking carbon stars astracers, we find a flat rotation curve of 210 ± 12kms-1 assuming R0 = 8.0 kpc for thegalactocentric distance and V0 = 220 kms-1for the rotation velocity of the Sun. Due to the uncertainties ofdistances, the rotation velocities are more dispersed if tangentialvelocities enter the calculation, compared to those derived from radialvelocities only. However, the whole rotation curve shows coherence withprevious results. Increasing observation and study of carbon stars wouldbe desirable in order to provide more homogeneous data for thekinematical study of the Galactic disk.
| AKARI's infrared view on nearby stars. Using AKARI infrared camera all-sky survey, 2MASS, and Hipparcos catalogs
Context. The AKARI, a Japanese infrared space mission, has performed anAll-Sky Survey in six infrared-bands from 9 to 180 ?m with higherspatial resolutions and better sensitivities than IRAS. Aims: Weinvestigate the mid-infrared (9 and 18 ?m) point source catalog (PSC)obtained with the infrared camera (IRC) onboard AKARI, in order tounderstand the infrared nature of the known objects and to identifypreviously unknown objects. Methods: Color-color diagramsand a color-magnitude diagram were plotted with the AKARI-IRC PSCand other available all-sky survey catalogs. We combined the Hipparcosastrometric catalog and the 2MASS all-sky survey catalog with theAKARI-IRC PSC. We furthermore searched literature and SIMBADastronomical database for object types, spectral types, and luminosityclasses. We identified the locations of representative stars and objectson the color-magnitude and color-color diagram schemes. Theproperties of unclassified sources can be inferred from their locationson these diagrams. Results: We found that the (B-V) vs.(V-S9W) color-color diagram is useful for identifying thestars with infrared excess emerged from circumstellar envelopes ordisks. Be stars with infrared excess are separated well from other typesof stars in this diagram. Whereas (J-L18W) vs. (S9W-L18W)diagram is a powerful tool for classifying several object types.Carbon-rich asymptotic giant branch (AGB) stars and OH/IR stars formdistinct sequences in this color-color diagram. Young stellarobjects (YSOs), pre-main sequence (PMS) stars, post-AGB stars, andplanetary nebulae (PNe) have the largest mid-infrared color excess andcan be identified in the infrared catalog. Finally, we plot the L18W vs.(S9W-L18W) color-magnitude diagram, using the AKARI data togetherwith Hipparcos parallaxes. This diagram can be used to identify low-massYSOs and AGB stars. We found that this diagram is comparable to the [24]vs. ([8.0]-[24]) diagram of Large Magellanic Cloud sources usingthe Spitzer Space Telescope data. Our understanding of Galactic objectswill be used to interpret color-magnitude diagram of stellar populationsin the nearby galaxies that Spitzer Space Telescope observed. Conclusions: Our study of the AKARI color-color andcolor-magnitude diagrams will be used to explore properties ofunknown objects in the future. In addition, our analysis highlights afuture key project to understand stellar evolution with a circumstellarenvelope, once the forthcoming astronometrical data with GAIA areavailable.Catalog (full Tables 3 and 4) are only available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/514/A2
| Infrared Study of J-Type Carbon Stars Based on Infrared Astronomical Satellite, Two Micron All Sky Survey, and Infrared Space Observatory Data
We collected 113 J-type carbon stars from the published literature.Observations from 2MASS, IRAS, and ISO show that, except for silicatecarbon stars in the J-type carbon star domain, the infrared propertiesof the other J-type carbon stars are quite similar to those of ordinarycarbon stars. The above results imply that the chemical peculiarity ofenhanced 13C for J-type carbon stars is not reflected in theinfrared region. In addition, the possible evolutionary scenario andbinarity for J-type carbon stars are also discussed.
| Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
| Proper motions and CCD-photometry of stars in the region of the open cluster Trumpler 2
The results of a complex study of the galactic open cluster Trumpler 2are presented. In order to obtain the proper motions, the positions ofapproximately 3000 stars up to the limit magnitude B˜16.25 mag inthe area 80 arcmin×80 arcmin around the cluster were measured on 6plates with a maximal epoch difference of 63 years. The root-mean errorof the relative proper motions is 4.2 mas yr-1. The catalogueof {BV} magnitudes of all the stars in the investigated area wascompiled. The selection of the cluster members within the region ofR<16 arcmin from the center of the cluster was made. Altogether, 148stars were considered to be cluster members by both astrometrical andphotometrical criteria. We present the estimated age(8.91×107 yr) and physical parameters of the clusterand append the catalogues of the proper motions and of the photometry ofthe stars.
| Tycho-2 stars with infrared excess in the MSX Point Source Catalogue
Stars of all evolutionary phases have been found to have excess infraredemission due to the presence of circumstellar material. To identify suchstars, we have positionally correlated the infrared Mid-Course SpaceExperiment (MSX) Point Source Catalogue and the Tycho-2 opticalcatalogue. Near-mid-infrared colour criteria have been developed toselect infrared excess stars. The search yielded 1938 excess stars; overhalf (979) have never previously been detected by IRAS. The excess starswere found to be young objects such as Herbig Ae/Be and Be stars, andevolved objects such as OH/IR (infrared) and carbon stars. A number ofB-type excess stars were also discovered whose infrared colours couldnot be readily explained by known catalogued objects.
| Near-infrared photometry of 20 hipparcos carbon stars
Near-infrared JHK photometry was carried out for 20 carbon starsobserved by the satellite Hipparcos. From the observations, bolometriccorrections in the K band (BCK), apparent bolometricmagnitudes (mrmbo) and effective temperatures (Te)of these stars were estimated. Combined with the trigonometricparallaxes measured by Hipparcos, the absolute bolometric magnitudes(Mbol) of some of the stars were obtained.
| 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
| Spectral Classification of Faint Carbon Stars
R--N classification of 187 faint carbon stars is based on the classicalcriteria adjusted to the yellow-red spectral region, with two newcriteria added -- the ratios of the red CN bands 6206/6332 (Å) and6478/6631 (Å).
| Carbon-rich giants in the HR diagram and their luminosity function
The luminosity function (LF) of nearly 300 Galactic carbon giants isderived. Adding BaII giants and various related objects, about 370objects are located in the RGB and AGB portions of the theoretical HRdiagram. As intermediate steps, (1) bolometric corrections arecalibrated against selected intrinsic color indices; (2) the diagram ofphotometric coefficients 1/2 vs. astrometric trueparallaxes varpi are interpreted in terms of ranges of photosphericradii for every photometric group; (3) coefficients CR andCL for bias-free evaluation of mean photospheric radii andmean luminosities are computed. The LF of Galactic carbon giantsexhibits two maxima corresponding to the HC-stars of the thick disk andto the CV-stars of the old thin disk respectively. It is discussed andcompared to those of carbon stars in the Magellanic Clouds and Galacticbulge. The HC-part is similar to the LF of the Galactic bulge,reinforcing the idea that the Bulge and the thick disk are part of thesame dynamical component. The CV-part looks similar to the LF of theLarge Magellanic Cloud (LMC), but the former is wider due to thesubstantial errors on HIPPARCOS parallaxes. The obtained meanluminosities increase with increasing radii and decreasing effectivetemperatures, along the HC-CV sequence of photometric groups, except forHC0, the earliest one. This trend illustrates the RGB- and AGB-tracks oflow- and intermediate-mass stars for a range in metallicities. From acomparison with theoretical tracks in the HR diagram, the initial massesMi range from about 0.8 to 4.0 Msun for carbongiants, with possibly larger masses for a few extreme objects. A largerange of metallicities is likely, from metal-poor HC-stars classified asCH stars on the grounds of their spectra (a spheroidal component), tonear-solar compositions of many CV-stars. Technetium-rich carbon giantsare brighter than the lower limit Mbol =~ -3.6+/- 0.4 andcentered at =~-4.7+0.6-0.9 at about =~(2935+/-200) K or CV3-CV4 in our classification. Much like the resultsof Van Eck et al. (\cite{vaneck98}) for S stars, this confirms theTDU-model of those TP-AGB stars. This is not the case of the HC-stars inthe thick disk, with >~ 3400 K and>~ -3.4. The faint HC1 and HC2-stars( =~ -1.1+0.7-1.0) arefound slightly brighter than the BaII giants ( =~-0.3+/-1.3) on average. Most RCB variables and HdC stars range fromMbol =~ -1 to -4 against -0.2 to -2.4 for those of the threepopulation II Cepheids in the sample. The former stars show the largestluminosities ( <~ -4 at the highest effectivetemperatures (6500-7500 K), close to the Mbol =~ -5 value forthe hot LMC RCB-stars (W Men and HV 5637). A full discussion of theresults is postponed to a companion paper on pulsation modes andpulsation masses of carbon-rich long period variables (LPVs; Paper IV,present issue). This research has made use of the Simbad databaseoperated at CDS, Strasbourg, France. Partially based on data from theESA HIPPARCOS astrometry satellite. Table 2 is only available inelectronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/390/967
| 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.
| 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).
| The effective temperatures of carbon-rich stars
We evaluate effective temperatures of 390 carbon-rich stars. Theinterstellar extinction on their lines of sights was determined andcircumstellar contributions derived. The intrinsic (dereddened) spectralenergy distributions (SEDs) are classified into 14 photometric groups(HCi, CVj and SCV with i=0,5 and j=1,7). The newscale of effective temperatures proposed here is calibrated on the 54angular diameters (measured on 52 stars) available at present from lunaroccultations and interferometry. The brightness distribution on stellardiscs and its influence on diameter evaluations are discussed. Theeffective temperatures directly deduced from those diameters correlatewith the classification into photometric groups, despite the large errorbars on diameters. The main parameter of our photometric classificationis thus effective temperature. Our photometric < k right >1/2 coefficients are shown to be angular diameters on arelative scale for a given photometric group, (more precisely for agiven effective temperature). The angular diameters are consistent withthe photometric data previously shown to be consistent with the trueparallaxes from HIPPARCOS observations (Knapik, et al. \cite{knapik98},Sect. 6). Provisional effective temperatures, as constrained by asuccessful comparison of dereddened SEDs from observations to modelatmosphere predictions, are in good agreement with the values directlycalculated from the observed angular diameters and with those deducedfrom five selected intrinsic color indices. These three approaches wereused to calibrate a reference angular diameter Phi 0 and theassociated coefficient CT_eff. The effective temperatureproposed for each star is the arithmetic mean of two estimates, one(``bolometric'') from a reference integrated flux F0, theother (``spectral'') from calibrated color indices which arerepresentative of SED shapes. Effective temperatures for about 390carbon stars are provided on this new homogeneous scale, together withvalues for some stars classified with oxygen-type SEDs with a total of438 SEDs (410 stars) studied. Apparent bolometric magnitudes are given.Objects with strong infrared excesses and optically thick circumstellardust shells are discussed separately. The new effective temperaturescale is shown to be compatible and (statistically) consistent with thesample of direct values from the observed angular diameters. Theeffective temperatures are confirmed to be higher than the mean colortemperatures (from 140 to 440 K). They are in good agreement with thepublished estimates from the infrared flux method forTeff>= 3170 K, while an increasing discrepancy is observedtoward lower temperatures. As an illustration of the efficiency of thephotometric classification and effective temperature scale, the C/Oratios and the Merrill-Sanford (M-S) band intensities are investigated.It is shown that the maximum value, mean value and dispersion of C/Oincrease along the photometric CV-sequence, i.e. with decreasingeffective temperature. The M-S bands of SiC2 are shown tohave a transition from ``none'' to ``strong'' at Teff =~(2800+/- 150right ) K. Simultaneously, with decreasing effectivetemperature, the mean C/O ratio increases from 1.04 to 1.36, thetransition in SiC2 strength occurring while 1.07<= C/O<= 1.18. This research has made use of the Simbad database operatedat CDS, Strasbourg, France. Table 10 is only available in electronicform at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5)}or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/369/178
| General Catalog of Galactic Carbon Stars by C. B. Stephenson. Third Edition
The catalog is an updated and revised version of Stephenson's Catalogueof Galactic Cool Carbon Stars (2nd edition). It includes 6891 entries.For each star the following information is given: equatorial (2000.0)and galactic coordinates, blue, visual and infrared magnitudes, spectralclassification, references, designations in the most significantcatalogs and coordinate precision classes. The main catalog issupplemented by remarks containing information for which there was noplace in entries of the main part, as well as some occasional notesabout the peculiarities of specific stars.
| Quantitative analysis of carbon isotopic ratios in carbon stars. III. 26 J-type carbon stars including 5 silicate carbon stars
We present the result of a quantitative analysis of (12C/({13)) C}ratios in 26 J-type carbon stars. The (12C/({13)) C} ratios aredetermined from lines of the CN red system around 8000 Angstroms, usingthe iso-intensity method and line-blanketed model atmospheres. Theaverage of (12C/({13)) C}\ ratios in the 26 stars is 4.7 +/- 2.8(standard deviation). All the stars studied, except for two stars, have(12C/({13)) C}\ ratios smaller than 10. (12C/({13)) C}\ ratios as low as1 ~ 2, which are lower than the value at the equilibrium of theCN-cycle, are found for a significant fraction of our sample, suggestingthe operation of non-equilibrium nuclear processes. For several starspreviously analyzed by other authors, our result shows fair agreement.The serious disagreement of (12C/({13)) C}\ ratios, which we reportedfor N-type carbon stars in our preceding paper, is not found for J-typecarbon stars. Five silicate carbon stars in our sample show no peculiar(12C/({13)) C} ratios among the stars studied in the present work. Thisresult implies that the mechanism responsible for low (12C/({13)) C}\ratios in silicate carbon stars might be the same with that operating inother J-type carbon stars. In other words, (12C/({13)) C}\ ratios insilicate carbon stars have turned out to give few clues to identify themechanism responsible for their formation.
| 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.
| Photoelectric photometry of carbon stars in the Vilnius system
A total of 368 observations of magnitudes and color indices of 178carbon stars in the Vilnius seven-color photometric system are given.The observations are presented in a catalog.
| A general catalogue of cool carbon stars
Not Available
| Variability of Cool Carbon Stars Situated Near or in Intermediate-Age Open Clusters
Not Available
| Distances and luminosities of irregular variables of type N
Near-IR photometric data obtained by Baumert (1972) are presented for asubgroup of 107 irregular and semirregular N variables, and it issuggested that variations in the (0.78-1.08)-micron color indices ofthese stars are primarily due to interstellar reddening. On this basis,the distances of 60 stars are estimated from color excesses in (B - V),and luminosities are derived from photometric data relative to Vega andthe observed flux distribution to 14 microns from 19 Psc, which is takenas a prototype N irregular star. The estimated distances are shown to besupported by the Oort double-sine distribution of radial velocities, anapparent association with galactic spiral features, and agreement withprevious bolometric corrections. A dispersion in bolometric magnitude isfound in a Keenan-Morgan C subclass, with that parameter increasing froman average value of -4.4 in C4 stars to an average value of -5.6 in C7stars. Near-IR CN bands are found not to correlate with luminosity,while the Merrill-Sanford bands are found to be negative luminosityindicators.
| Cool Carbon Stars in Open Clusters (abstract)
Not Available
| Carbon stars in the northern Milky Way.
Abstract image available at:http://adsabs.harvard.edu/abs/1973A&A....22..129H
| A general catalogue of cool carbon stars
Not Available
| Carbon Stars in Two Northern Milky way Zones.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1957ApJ...125..195N&db_key=AST
| Variable stars in open clusters.
Not Available
| Carbon Stars in Zones 40[degrees] to 90[degrees]. Dearborn Survey of Faint Red Stars
This Part 7 of the Annals is a continuation of the list of carbon starsin the Dearborn Survey of Faint Red Stars (stars 234 to 365).
| Radial Velocities of 283 Stars of Spectral Classes R and N.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1944ApJ....99..145S&db_key=AST
| Additional stars of classes N and S-second list
Not Available
| 14 neue Veraenderliche.
Not Available
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| Sað Açýklýk: | 02h38m43.09s |
| Yükselim: | +55°45'59.4" |
| Görünürdeki Parlaklýk: | 10.956 |
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