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Red giants in open clusters. XIV. Mean radial velocities for 1309 stars and 166 open clusters
Context: Radial velocities have proved to be an efficient method formembership determination if there are at least 2 or 3 red giants in acluster. They are necessary for galactic studies, but are still missingfor many open clusters. Aims: We present the final catalogues of along-term observing programme performed with the two coravelspectrovelocimeters for red giants in open clusters. The main aims wereto detect spectroscopic binaries and determine their orbital parameters,determine the membership, and compute mean velocities for the stars andopen clusters. Methods: We computed weighted mean radial velocities for1309 stars from 10 517 individual observations, including the systemicradial velocities from spectroscopic orbits and for cepheids. Results:The final results are contained in three catalogues collecting 10 517individual radial velocities, mean radial velocities for 1309 redgiants, and mean radial velocities for 166 open clusters among whichthere are 57 new determinations. We identified 891 members and 418non-members. We discovered a total of 288 spectroscopic binaries, amongwhich 57 are classified as non-members. In addition 27 stars were judgedto be variable in radial velocities and they are all red supergiants. Conclusions: The present material, combined with recent absolute propermotions, will permit various investigation of the galactic distributionand space motions of a large sample of open clusters. However, thedistance estimates still remain the weakest part of the necessary data.This paper is the last one in this series devoted to the study of redgiants in open clusters based on radial velocities obtained with thecoravel instruments.Based on observations collected at the Haute-Provence Observatory(France) and on observations collected with the Danish 1.54-m telescopesat the European Southern Observatory, La Silla, Chile. Full Tables [seefull textsee full textsee full textsee full textsee full text] to [seefull textsee full textsee full textsee full textsee full text] are onlyavailable and Tables [see full textsee full textsee full textsee fulltextsee full text] and [see full textsee full textsee full textsee fulltextsee full text] are also 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/485/303
| The Presence of Diffuse Interstellar Bands in the Spectra of Cool Stars
Data from the Kitt Peak National Observatory (KPNO) coudé feedtelescope were used to analyze the strength of three well-known diffuseinterstellar bands (DIBs; 5780, 5797, and 6614 Å). Ten mid-A,mid-F, and mid-G stars with moderate reddening (EB-V=0.2-1.2)were observed, along with one reddened B0 dwarf for comparison.Synthetic spectra were calculated to remove the interference of stellarfeatures. We report the detection of all three DIBs in A, F, and Gstars. We also find the correlation of DIB strengths with E(B-V), in oursight lines, to be consistent with previous results from Herbig (1993),demonstrating that DIB strength is not dependent on the spectral type ofthe target star.
| Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
| Stellar populations in Seyfert 2 galaxies. I. Atlas of near-UV spectra
We have carried out a uniform spectroscopic survey of Seyfert 2 galaxiesto study the stellar populations of the host galaxies. New spectra havebeen obtained for 79 Southern galaxies classified as Seyfert 2 galaxies,7 normal galaxies, and 73 stars at a resolution of 2.2 Å over thewavelength region 3500-5300 Å. Cross-correlation between thestellar spectra is performed to group the individual observations into44 synthesis standard spectra. The standard groups include a solarabundance sequence of spectral types from O5 to M3 for dwarfs, giants,and supergiants. Metal-rich and metal-weak F-K giants and dwarfs arealso included. A comparison of the stellar data with previouslypublished spectra is performed both with the individual spectra and thestandard groups. For each galaxy, two distinct spatial regions areconsidered: the nucleus and the external bulge. Spectroscopic variationsfrom one galaxy to another and from the central to the external regionare briefly discussed. It is found that the central region of a Seyfert2 galaxy, after subtracting the bulge stellar population, always shows anear-UV spectrum similar to one of three representative categories: a)many strong emission lines and only two visible absorption lines (Ca IiK and G band) (Sey2e); b) few emission lines, many absorption lines, anda redder continuum than the previous category (Sey2a); c) an almost flatcontinuum and high-order Balmer lines seen in absorption (Sey2b). Theproportion of Seyfert 2 galaxies belonging to each class is found to be22%, 28%, and 50% respectively. We find no significative differencesbetween morphology distributions of Seyfert 2 galaxies with Balmer linesdetected in absorption and the rest of the sample. This quick lookthrough the atlas indicates that half of Seyfert 2 galaxies harbour ayoung stellar population (about or less than 100 Myr) in their centralregion, clearly unveiled by the high order Balmer series seen inabsorption. Based on observations collected at the European SouthernObservatory, Chile (ESO 65.P-0014(A)). Tables 1-3 and 8 and Fig. A.1(Appendix A) are only available in electronic form athttp://www.edpsciences.org
| Catalogue of [Fe/H] determinations for FGK stars: 2001 edition
The catalogue presented here is a compilation of published atmosphericparameters (Teff, log g, [Fe/H]) obtained from highresolution, high signal-to-noise spectroscopic observations. This newedition has changed compared to the five previous versions. It is nowrestricted to intermediate and low mass stars (F, G and K stars). Itcontains 6354 determinations of (Teff, log g, [Fe/H]) for3356 stars, including 909 stars in 79 stellar systems. The literature iscomplete between January 1980 and December 2000 and includes 378references. The catalogue is made up of two tables, one for field starsand one for stars in galactic associations, open and globular clustersand external galaxies. The catalogue is distributed through the CDSdatabase. Access to the catalogue with cross-identification to othersets of data is also possible with VizieR (Ochsenbein et al.\cite{och00}). The catalogue (Tables 1 and 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/373/159 and VizieRhttp://vizier.u-strasbg.fr/.
| Absolute proper motions of open clusters. I. Observational data
Mean proper motions and parallaxes of 205 open clusters were determinedfrom their member stars found in the Hipparcos Catalogue. 360 clusterswere searched for possible members, excluding nearby clusters withdistances D < 200 pc. Members were selected using ground basedinformation (photometry, radial velocity, proper motion, distance fromthe cluster centre) and information provided by Hipparcos (propermotion, parallax). Altogether 630 certain and 100 possible members werefound. A comparison of the Hipparcos parallaxes with photometricdistances of open clusters shows good agreement. The Hipparcos dataconfirm or reject the membership of several Cepheids in the studiedclusters. Tables 1 and 2 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Comparative abundance analysis of the hot main sequence stars and their progeny in open cluster M 25
Remarkable inconsistencies between elemental abundances in the mainsequence stars and their progeny F-G supergiants are discussed.Comparative abundance analysis of the hot main sequence stars, thecepheid U Sgr and two cool supergiants belonging to young open cluster M25 is performed. The detected disaccord in the abundances of carbon,oxygen and other elements between these stars having a common origin butoccupying at present different evolutionary stages may be due to thefact that the chemical anomalies observed in B stars are caused by themechanism of the radiative diffusion in the upper atmosphere layers. Thechemical composition of B stars determined spectroscopically may notreflect correctly their true chemical composition, nor the chemicalcomposition of the interstellar medium. On the other hand such abundanceanomalies are not expected for F-G supergiants which have suffered thelarge scale mixing in the red giant phase. The observed abundances forthese objects are much more reliable as a reference point in the studyof galactic chemical evolution. Three new Be stars are discovered in M25. Our study has doubled the number of Be stars known in this cluster.
| HIPPARCOS data for two open clusters containing cepheids
Using proper motion data from the Hipparcos satellite it is shown thatthe cepheids S Nor and U Sgr are members of the open clusters NGC 6087and M 25, respectively. The precision of the Hipparcos data is needed toconclusively carry out a membership test. Parallax data, also obtainedfrom Hipparcos, do not contradict the proper motion results.
| A catalogue of [Fe/H] determinations: 1996 edition
A fifth Edition of the Catalogue of [Fe/H] determinations is presentedherewith. It contains 5946 determinations for 3247 stars, including 751stars in 84 associations, clusters or galaxies. The literature iscomplete up to December 1995. The 700 bibliographical referencescorrespond to [Fe/H] determinations obtained from high resolutionspectroscopic observations and detailed analyses, most of them carriedout with the help of model-atmospheres. The Catalogue is made up ofthree formatted files: File 1: field stars, File 2: stars in galacticassociations and clusters, and stars in SMC, LMC, M33, File 3: numberedlist of bibliographical references The three files are only available inelectronic form at the Centre de Donnees Stellaires in Strasbourg, viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5), or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Colour excesses of F-G supergiants and Cepheids from Geneva photometry.
A reddening scale for F-G supergiants and Cepheids is presented.Supergiants with low reddenings or in clusters form the basis of thecalibration. In this sense, it is entirely empirical. The data have beenobtained in the Geneva photometric system. Comparisons with otherreddening scales show no disagreement. The only problem is with Fernie'sscale for Cepheids (1990), where a systematic trend exists. Its originis not clear. It is suggested to extend the number of supergiants withindependently obtained colour excesses in order to test the existence ofa possible luminosity dependence of the calibration. A period-colourrelation for Cepheids is deduced, on the basis of the present reddeningcorrections. It gives strong support for V473 Lyr being a secondovertone pulsator.
| 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.
| Photometry of F-K type bright giants and supergiants. 3: The luminosity, reddening, and heavy element abundance of GK stars
The reddening, luminosity, and heavy element abundance of 250 brightgiants and supergiants of type GK are discussed on the basis of 4 color,DDO, RI, and Geneva photometry Bright giants of type GK with age greaterthan 5 x 108 yr, and of type G0/3 with age greater than 2 x108 yr, are very scarce in the solar neighborhood. The medianspace motion vectors of the bright giants and supergiants with welldetermined space motions are (U, V, W) = (+10.6, -13.2, -7.7) +/- (12.3,8.8, 8.8) km/s. The M1 index for 4 color photometry, whencorrected for luminosity (gravity) effects, is sensitive to heavyelement abundance of the GK stars but may not be reliable for those oftype G0/3. The available spectroscopic determinations of (Fe/H) givemixed results with the two largest samples being internally consistentbut with a large zero-point difference. There is a similar zero-pointshift in the peak frequency of the photometrically determined values ofP(Fe/H) for the F type and for the GK type stars. There is littleevidence for an appreciable galactic, radial gradient in the P(Fe/H)values. A previously noted correlation of the heavy element abundanceindex, delta M1, with the amplitude defect in the B lightcurves of Cepheids, FB, and interpretation of the(PLFB) relation as a (PL(Fe/H)) relation needs furtherinvestigation in light of the apparent sensitivity of M1 toFe/H for the F stars (the domain of the Cepheids with P less than 10 d)and lack of this sensitivity for the G0/3 star (domain of the Cepheidswith P greater than 10 d).
| Open cluster chemical composition. 1: Later type stars in eight clusters
Abundance analyses of 36 stars associated with eight open clusters (IC2581, NGC 3532, NGC 5822, NGC 6067, NGC 6087, IC 4725 (M25), IC 4756,and NGC 6882/6885) are presented. The stars are primarily evolved G andK giants and supergiants. Cepheids in NGC 6067, NGC 6087, and IC 4725are included as are non-cluster Cepheids near the clusters NGC 3532, NGC6067, and IC 4725. With the addition of a background K giant in IC 4725,the total number of stars is 40. Elemental abundances derived includeLi, C, N, O, the alpha-elements, the Fe peak, and limited data on theheavy elements. The Na abundances of the sample show a gravitydependence in the sense of an increase in the abundance as the gravitydecreases. The CNO abundances indicate that these objects are processed(on the whole), and that they show the O deficiency previously noted inintermediate mass stars by Luck & Lambert (1981, 1985). There arefour stars in the sample which appear to be unprocessed: two giants andtwo supergiants. There are also two super-Li stars in the sample, one ofwhich is most likely a weak G-band star. It is suggested that thesuper-Li F supergiants could be evolved blue stragglers. The moststriking result of the study is the finding that the (O/Na) ratiocorrelates strongly with the gravity and the stellar mass, thus implyingthat there is a nonstandard additional mixing process affecting thesurface abundances of these stars. A promising candidate for the mixingprocess is the turbulent diffusive mixing process proposed byDenissenkov (1993) which brings Na to the surface and which could alsolead to a modification of the oxygen content.
| A catalogue of Fe/H determinations - 1991 edition
A revised version of the catalog of Fe/H determinations published by G.Cayrel et al. (1985) is presented. The catalog contains 3252 Fe/Hdeterminations for 1676 stars. The literature is complete up to December1990. The catalog includes only Fe/H determinations obtained from highresolution spectroscopic observations based on detailed spectroscopicanalyses, most of them carried out with model atmospheres. The catalogcontains a good number of Fe/H determinations for stars from open andglobular clusters and for some supergiants in the Magellanic Clouds.
| 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.
| 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.
| Groups of stars with common motion in the Galaxy - Groups of red supergiants of the luminosity classes I and II
Not Available
| Membership of Cepheids and red giants in 8 open clusters - NGC 129, 6067, 6087, 6649, 6664, IC 4725, LY 6, RU 79
The membership of eight cluster Cepheids,DL Cas,EV Sct, V367 Sct, S Nor,TW Nor,V340 Nor, U Sgr and CS Vel, has been examined by comparing theirsystemic radial velocity with that observed for the red giants in thesame clusters. The membership is very probable in seven cases, theonly-exception being CS Vel. Additional observations of main sequencestars are necessary to confirm some of the conclusions. Onespectroscopic binary was discovered among the Cepheids (DL Cas) and atleast four were among the red giants. Orbits have been determined fortwo red giants, one in NGC 129 and one in IC 4725. The position withinthe instability strip of the nonvariable F5Ib star in NGC 129 is due toits probable composite (gK + dB) character. The ratio of the number ofCepheids to the number of red giants is less than 1, in good agreementwith the prediction of evolutionary models with core overshooting. Thisstudy is based on 382 observations of 45 stars, obtained with the radialvelocity scanner CORAVEL.
| A catalogue of Fe/H determinations, 1984 edition
The present version of the Cayrel de Strobel et al. (1981) catalog ofFe/H abundance ratio determinations contains 1921 values for 1035 stars,which represents an augmentation over the previous publication of 48 and47 percent, respectively. In addition, the literature search conductedis complete up to December, 1983. Stellar metal abundance, effectivetemperature, spectroscopic gravity, spectral type, and photometricindices are covered.
| The reddening, metal abundance, and luminosity of high-luminosity G-type stars
The abundance parameters of the sample of 100 G-type bright giants andsupergiants whose photometry is presently discussed indicate Fe/H valuesof between about + 0.6 dex and the solar value, using a preliminarycalibration of the photometric indices. The few long period Cepheidsthat are not heavily blanketed F-type stars give reddening values thatare in agreement with current results from other methods of analysis.Supergiants show no clear gradients in the galactic distribution ofabundances, and those nearest the sun range from an Fe/H of about + 0.3dex, for members of the Pleiades Group, to near solar abundance. A smallsample of Large Magellanic Cloud supergiants shows nearly the same rangein metal abundance as the galactic stars, and gives a modulus for thisCloud of 18.3 + or - 0.20 mag.
| Four-color and H-beta photometry of the galactic cluster M25
Four-color and H-beta photometry has been done for 39 stars in thegalactic cluster M25. The data are used to remove nonmember stars fromthe sample and to determine which stars are cluster members. A meandistance modulus of 8.76 and color excess of E(b-y) = 0.341 is found.
| DDO Observations of Southern Stars
Not Available
| Photoelectric observations of lunar occultations. XI
Occultation observations of 466 events are presented. These includediameter measures of Aldebaran under very bad conditions and a gooddiameter measure of 82 Vir. The list includes 91 reappearances andobservations of 34 double or multiple stars, both new and previouslyknown. The inconsistencies of the observations of Kui 88 are discussed.Further observations are most desirable.
| A photoelectric measurement of magnesium for late-type stars
A photoelectric index of MgH + Mg b for late-type stars has been createdby the addition of one filter bandpass to the DDO system. Measurementsshow that this index has good sensitivity to surface gravity for Kstars, and suggest that it can differentiate metal-poor halo giants fromdisk stars. From this index, involving measurement through two filtersalone, it appears that membership can be determined for stars on thegiant branch of globular clusters. It is possible that the index couldbe used, after calibration with cluster giants, to determine ages ofgiant stars in the field.
| 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
| Sodium in late-type stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970A&A.....7..408C&db_key=AST
| Photometry of bright southern cepheids
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970MNRAS.148....1S&db_key=AST
| Metal-to-H ratios in the Galaxy as indicated by narrow-band photometry of Cepheids.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966AJ.....71..615W&db_key=AST
| Polarization of Galactic Clusters M25, NGC 869, 884, 1893, 2422, 6823, 6871, and Association VI Cygni.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1965ApJ...141.1340S&db_key=AST
| The Chemical Composition of Yellow Giants in Six Galactic Clusters.
Abstract image available at:http://adsabs.harvard.edu/abs/1964ApJ...140..858W
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Osservazione e dati astrometrici
| Costellazione: | Sagittario |
| Ascensione retta: | 18h32m29.17s |
| Declinazione: | -18°58'21.5" |
| Magnitudine apparente: | 6.995 |
| Distanza: | 2272.727 parsec |
| Moto proprio RA: | -1.3 |
| Moto proprio Dec: | -4.8 |
| B-T magnitude: | 8.769 |
| V-T magnitude: | 7.142 |
Cataloghi e designazioni:
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