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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
| Evolution of X-ray activity and rotation on G-K giants
The recent availability of stellar parallaxes provided by the Hipparcosstar catalogue (ESA 1997) enables an accurate determination of thepositions of single field giants in a theoretical H-R diagram and areliable estimate of their masses. The present study combines these newastrometric data with previously published X-ray fluxes and rotationalvelocities. The results confirm the existence of a sharp decrease ofX-ray emission at spectral type K1 for 2.5 M_sun < M < 5 M_sungiants. The study shows that the rotational velocity of these starsreaches a minimum at the same location in the H-R diagram. However, notight relationship between X-ray luminosities and projected equatorialvelocities was found among the sample stars. I suggest that theseresults could reflect the importance of differential rotation indetermining the level of coronal emission among >= 2.5Msun G and K giants. The restoration of rigid rotation at thebottom of the red giant branch could prevent the maintenance of largescale magnetic fields, thus explaining the sharp decrease of coronalX-ray emission at spectral type K1.
| Determination of the temperatures of selected ISO flux calibration stars using the Infrared Flux Method
Effective temperatures for 420 stars with spectral types between A0 andK3, and luminosity classes between II and V, selected for a fluxcalibration of the Infrared Space Observatory, ISO, have been determinedusing the Infrared Flux Method (IRFM). The determinations are based onnarrow and wide band photometric data obtained for this purpose, andtake into account previously published narrow-band measures oftemperature. Regression coefficients are given for relations between thedetermined temperatures and the photometric parameters (B2-V1), (b-y)and (B-V), corrected for interstellar extinction through use ofHipparcos parallaxes. A correction for the effect of metallicity on thedetermination of integrated flux is proposed. The importance of aknowledge of metallicity in the representation of derived temperaturesfor Class V, IV and III stars by empirical functions is discussed andformulae given. An estimate is given for the probable error of eachtemperature determination. Based on data from the ESA HipparcosAstrometry Satellite.
| Towards a fundamental calibration of stellar parameters of A, F, G, K dwarfs and giants
I report on the implementation of the empirical surface brightnesstechnique using the near-infrared Johnson broadband { (V-K)} colour assuitable sampling observable aimed at providing accurate effectivetemperatures of 537 dwarfs and giants of A-F-G-K spectral-type selectedfor a flux calibration of the Infrared Space Observatory (ISO). Thesurface brightness-colour correlation is carefully calibrated using aset of high-precision angular diameters measured by moderninterferometry techniques. The stellar sizes predicted by thiscorrelation are then combined with the bolometric flux measurementsavailable for a subset of 327 ISO standard stars in order to determineone-dimensional { (T, V-K)} temperature scales of dwarfs and giants. Theresulting very tight relationships show an intrinsic scatter induced byobservational photometry and bolometric flux measurements well below thetarget accuracy of +/- 1 % required for temperature determinations ofthe ISO standards. Major improvements related to the actual directcalibration are the high-precision broadband { K} magnitudes obtainedfor this purpose and the use of Hipparcos parallaxes for dereddeningphotometric data. The temperature scale of F-G-K dwarfs shows thesmallest random errors closely consistent with those affecting theobservational photometry alone, indicating a negligible contributionfrom the component due to the bolometric flux measurements despite thewide range in metallicity for these stars. A more detailed analysisusing a subset of selected dwarfs with large metallicity gradientsstrongly supports the actual bolometric fluxes as being practicallyunaffected by the metallicity of field stars, in contrast with recentresults claiming somewhat significant effects. The temperature scale ofF-G-K giants is affected by random errors much larger than those ofdwarfs, indicating that most of the relevant component of the scattercomes from the bolometric flux measurements. Since the giants have smallmetallicities, only gravity effects become likely responsible for theincreased level of scatter. The empirical stellar temperatures withsmall model-dependent corrections are compared with the semiempiricaldata by the Infrared Flux Method (IRFM) using the large sample of 327comparison stars. One major achievement is that all empirical andsemiempirical temperature estimates of F-G-K giants and dwarfs are foundto be closely consistent between each other to within +/- 1 %. However,there is also evidence for somewhat significant differential effects.These include an average systematic shift of (2.33 +/- 0.13) % affectingthe A-type stars, the semiempirical estimates being too low by thisamount, and an additional component of scatter as significant as +/- 1 %affecting all the comparison stars. The systematic effect confirms theresults from other investigations and indicates that previousdiscrepancies in applying the IRFM to A-type stars are not yet removedby using new LTE line-blanketed model atmospheres along with the updatedabsolute flux calibration, whereas the additional random component isfound to disappear in a broadband version of the IRFM using an infraredreference flux derived from wide rather than narrow band photometricdata. Table 1 and 2 are only available in the electronic form of thispaper
| 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.
| Evolved GK stars near the sun. I - The old disk population
A sample of nearly two thousand GK giants with intermediate band, (R,I),DDO and Geneva photometry has been assembled. Astrometric data is alsoavailable for most of the stars. The some 800 members of the old diskpopulation in the sample yield accurate luminosities (from two sources),reddening values and chemical abundances from calibrations of thephotometric parameters. Less than one percent of the objects arepeculiar in the sense that the flux distribution is abnormal. Thepeculiarity is signaled by strong CH (and Ba II) and weak CH. The CH+stars are all spectroscopic binaries, probably with white dwarfcompanions, whereas the CH- stars are not. A broad absorption band,centered near 3500 A, is found in the CH+ stars whereas the CH- objectshave a broad emission feature in the same region. The intensity of theseabsorptions and emissions are independent of the intensity of abnormalspectral features. Ten percent of the old disk sample have a heavyelement abundance from one and a half to three times the solar value.The distribution of the heavy element abundances is nearly a normal onewith a peak near solar abundance and ranges three times to one sixthsolar. The distribution of the (U, V) velocities is independent of theheavy element abundance and does not appear to be random. Ten percent ofthe old disk stars show a CN anomaly, equally divided between CN strongand CN weak. Several stars of individual astrometric or astrophysicalimportance are isolated.
| Optical Polarization of 1000 Stars Within 50-PARSECS from the Sun
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1993A&AS..101..551L&db_key=AST
| UBV(RI)c observations for 13 bright Cepheids
Photometry in the UBV(RI)c system has been obtained for 13 of thebrightest Cepheids in the southern sky available to the new SydneyUniversity Stellar Interferometer. The stars observed were Eta Aq1, 1Car, U Car, AX Cir, Beta Dor, Zeta Gem, T Mon, Kappa Pav, U Sgr, W Sgr,X Sgr, Y Sgr, and AH Vel. The main purpose of the photometry is toprovide current epoch data for the phases of the variables, although forseveral of the stars these data are also the first in the (RI)c system.
| IUE and Einstein survey of late-type giant and supergiant stars and the dividing line
Results are presented on an IUE UV survey of 255 late-type G, K, and Mstars, complementing the Maggio et al. (1990) Einstein X-ray survey of380 late-type stars. The large data sample of X-ray and UV detectionsmake it possible to examine the activity relationship between the X-rayand the UV emissions. The results confirm previous finding of a trendinvolving a steeply-dropping upper envelope of the transition regionline fluxes, f(line)/f(V), as the dividing line is approached. Thissuggests that a sharp decrease in maximum activity accompanies theadvancing spectral type, with the dividing line corresponding to thissteep gradient region. The results confirm the rotation-activityconnection for stars in this region of the H-R diagram.
| 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.
| BVRI photometry of the Gliese Catalogue stars
Photoelectri BVRI photometry on the Cousins (Kron-Cape) system has beenobtained for many of the southern faint stars in the Gliese Catalog(1969). This extends the work of Cousins (1980) and provides a uniformset of data for the nearby stars. Several red dwarfs are noted, whichwere used to define the red end of the Cousins system.
| Large and Kinematically Unbiased Samples of G- and K-Type Stars. III. Evolved Young Disk Stars in the Bright Star Sample
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1989PASP..101...54E&db_key=AST
| Large and kinematically unbiased samples of G- and K-type stars. II - Observations of evolved stars in the Bright Star sample. III - Evolved young disk stars in the Bright Star sample
Four color and RI observations were obtained for a large sample ofG-type and K-type stars in the Bright Star Catalogue. Data are firstpresented for 110 evolved stars. Photometry of evolved young diskpopulation stars have then been calibrated for luminosity, reddening,and metallicity on the basis of results for members of the Hyades andSirius superclusters. New DDO results are given for 120 stars.
| Ultraviolet survey for hot companions among nonvariable yellow supergiants
Twenty nonvariable yellow supergiants have been observed for the firsttime with the International Ultraviolet Explorer satellite, with the aimof discovering hot companions. Two newly discovered systems areannounced: HD 74395 (G2 I + B9.5 IV-V) and HD 193469 (later than G0 + B8IV-V). The Cepheid HD 9250 was also observed, but no hot companion wasfound. Some stars independently known to have a hot companion wereincluded in order to study the properties of the companions and tocompare with previous work. Atmospheric models were used to fit theoverall energy distribution of the binary system, allowing an estimateof Te, log g, and the spectral type of the companion. The magnitudedifferences, in the V band, between the yellow supergiants and theircompanions were calculated. The possibility of using this magnitudedifference and the spectral type determined for the hot companions toestimate M(v) for the yellow supergiants and the distance to the systemsis explored. Comparison of the binaries' positions in the H-R diagramwith theoretical evolutionary tracks suggests that the masses of theprimaries are contained between 5 and 9 solar masses and that, onaverage, they are about twice as massive as their hot companions.
| Infrared spectra of WN stars. II - WN7 and WN8 stars
Moderate resolution (lambda/delta lambda less than 400) infrared spectrain the range 1-2.5 microns are presented for HD 86161(WN8), HD96548(WN8), and HD 151932(WN7). These data, in conjunction with existingoptical and UV data, will provide new insights into the structure ofWolf-Rayet stellar atmospheres, and are suitable for model input.
| Predicted infrared brightness of stars within 25 parsecs of the sun
Procedures are given for transforming selected optical data intoinfrared flux densities or irradiances. The results provide R, T(eff)blackbody approximations for about 2000 of the stars in Woolley et al.'sCatalog of Stars (1970) within 25 pc of the sun, and additional whitedwarfs, with infrared flux densities predicted for them at ninewavelengths from 2.2 to 101 microns including the Infrared AstronomySatellite bands.
| DDO Observations of Southern Stars
Not Available
| A survey of variable yellow supergiants in the southern Milky Way
Forty-three supergiants of spectral type F0-G8, including the RV Tauristar U Mon and the small-amplitude Cepheid HR 4768, have been monitoredin brightness for about a month. Three new variables are announced. HR6109 - a comparison star and a member of a spectroscopic binary with Pequals 40 days (Eggen 1973) - is suspected to be a Delta Scuti star. HR4912 shows a range of 0.32 magnitude in B; the period is between 44 and68 days. The Cepheid nature of HR 4912 cannot be established on thebasis of the data. HR 4110 - the central star of the galactic cluster IC2581 - shows a range in B of 0.07 magnitude and its most likely periodis about 59 days. Arguments are offered against the possible Cepheidinterpretation of HR 4110. The variability of HR 2910, HR 3026, and HD67458 is suspected. The star R Pup, which has been claimed anddisclaimed as a variable for a century, did not show significantvariation during the observing period.
| VRI photometry of nearby stars.
Not Available
| Catalogue of stars with CaII H and K emissions
Not Available
| Photometry of 5 galactic G-type supergiants
The paper examines photoelectric UBV photometry for 5 galacticsupergiants near spectral type GO. Low amplitude variations in magnitudeand color on a time scale of a few months are found in 4 of these stars,and the variability of the R Pup is confirmed. A classification of thesesupergiants in a new category of very long-period low-amplitudecepheid-like variables cannot be assessed because of the insufficienttime base of the observations, but the RV Tauri type variability canprobably be excluded. Finally, the incompleteness of statistics ofstable and low-amplitude variable galactic supergiants is noted, and thepossible coexistence of low-amplitude and large-amplitude variables inthe LMC cepheid instability strip is pointed out.
| Luminosity and velocity distributions of high-luminosity red stars. IV. The G-type giants
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974PASP...86..129E&db_key=AST
| Régions H II de l'hémisphère austral
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970A&AS....3....1G&db_key=AST
| Ca II K emission in southern late-type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969MNRAS.144..333W&db_key=AST
| Southern Cepheid Photometry.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1961ApJS....6..253I&db_key=AST
| Photoelectric determination of the colors of 286 stars south of declination -15 degrees.
Not Available
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Osservazione e dati astrometrici
| Costellazione: | Carena |
| Ascensione retta: | 11h06m32.40s |
| Declinazione: | -62°25'27.0" |
| Magnitudine apparente: | 4.61 |
| Distanza: | 113.379 parsec |
| Moto proprio RA: | -36.5 |
| Moto proprio Dec: | 10.1 |
| B-T magnitude: | 5.895 |
| V-T magnitude: | 4.719 |
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