CNO in evolved intermediate mass stars
In order to investigate the possible influence of rotation on theefficiency of the first dredge-up we determined atmospheric parameters,masses, and abundances of carbon, nitrogen, and oxygen in a sample ofevolved intermediate mass stars. We used high resolution spectra andconducted a model atmosphere analysis. The abundances were calculatedthrough spectral synthesis and compared to the predictions of rotatingand non-rotating evolutionary models. Almost all those objects in oursample where carbon and nitrogen abundances could be determined showsigns of internal mixing. The stars, however, seem to be mixed todifferent extents. Among the mixed stars we identify five in our samplewith abundances in agreement with the non-rotating models, four starsthat seem to be mixed beyond that, and one star that seems to beslightly less mixed than predicted for the first dredge-up. There arealso five stars that seem to be slightly more mixed than expected, buttheir abundances are in marginal agreement with both rotating andnon-rotating models. Such differences in the extent of the mixing arenot predicted by the standard models and imply the action of othermixing mechanisms than solely the convective dredge-up. We alsoidentified for the first time an important correlation between the [N/C]ratio and the stellar mass.
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A catalog of rotational and radial velocities for evolved stars. II. Ib supergiant stars
Rotational velocity vsin i and mean radial velocity are presented for asample of 231 Ib supergiant stars covering the spectral region F, G andK. This work is the second part of the large survey carried out with theCORAVEL spectrometer to establish the behavior of the rotation for starsevolving off the main sequence (De Medeiros & Mayor 1999). Thesedata will add constraints to the study of the rotational behavior inevolved stars, as well as solid information concerning tidalinteractions in binary systems and on the link between rotation,chemical abundance and activity in stars of intermediate masses. Basedon observations collected at the Haute-Provence Observatory,Saint-Michel, France and at the European Southern Observatory, La Silla,Chile Table 1 is 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/395/97
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Ca II H and K Filter Photometry on the UVBY System. II. The Catalog of Observations
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995AJ....109.2828T&db_key=AST
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Calibrations of Mv, (Fe/H), and log G for yellow supergiant stars from O I 7774 and uvby-beta data
New calibrations of the absolute magnitude Mv from O I 7774data are derived from narrow-band photometry and low dispersionspectroscopy for AO-G2 low and high luminosity stars. The nonlineardependence of Mv from the equivalent width W(OI) and therelevance of the stellar temperature in the calibration are confirmed inagreement with previous calibrations obtained from high resolutionspectroscopy. Also functional formulas to estimate (Fe/H) and log g fromuvby-beta data for FO-G3 supergiants are offered. These calibrationspredict iron abundances and gravities for yellow supergiants withuncertainties not much higher than good spectroscopic determinations.
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Photometry of F-K type bright giants and supergiants. I - Intermediate band and H-Beta observations
Over 1500 observations of 560 bright giants and supergiants of types F-Kare presented and compared to the observations by Gray and Olsen (1991).The present results include intermediate-band which is slightlydifferent from the Stromgren data by Gray and Olsen due to a differentwidth for the v filter. A systematic difference in m(1) - M(1) withdecreasing temperature is noted in the two H-Beta data sets, and thecorrelations are defined.
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A photometric study of the G0-4 Ia(+) hypergiant HD 96918 (V382 Carinae)
Using a photometric method we derive T(eff), log g, and E(B-V) for thestar HD 96918 and also for 35 supergiants of similar spectral class. ForHD 96918 we found T(eff) = 5200 +/- 200 K and log g (cm/sq s) = 0.0 +/-0.5. The comparison of the results indicates that HD 96918 is really ahypergiant with a spectral class around G0-G4. We also estimate thedistance of HD 96918 using the kinematic and reddening methods, and bycomparing its T(eff) and log g with evolutionary calculation. Weconsistently find a distance of 2.7 +/- 1.0 kpc which implies logL/solar luminosity = 5.5 +/- 0.4. A most probable mass for the star is20 +/- 10 solar mass.
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The calibration of the Stromgren photometric system for A, F and early G supergiants. I - The observational data
An empirical calibration of the Stromgren uvby-beta photometric systemfor the A, F, and early G supergiants is being derived. This paperexplains the observational program and the photometric reductiontechniques used and presents a catalog of new Stromgren photometry forover 600 A, F, and G supergiants.
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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.
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Valinhos 2.2 micron survey of the southern galactic plane. II - Near-IR photometry, IRAS identifications and nature of the sources
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1987A&AS...71...39E&db_key=AST
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Valinhos 2.2 micron survey of the Southern Galactic plane Positions and infrared photometry of 338 sources
This paper reports on JHKLM photometric measurements of 338 brightinfrared stars found in a 2.2-micron survey of a 10 x 100-deg lane ofthe Southern Galactic plane. More than 2/3 of the objects are notidentified with catalogued stars and are likely to belong-period-variable or reddened giant or supergiant stars.
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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
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Finding list and spectral classifications for southern luminous stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976AJ.....81..225M&db_key=AST
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Five-channel photometry of cepheids and supergiants in the southern Milky Way.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976A&AS...24..413P&db_key=AST
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INHABITED SKY
