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The effective temperature scale of giant stars (F0-K5). II. Empirical calibration of Teff versus colours and [Fe/H]
We present calibrations of the effective temperatures of giant starsversus [Fe/H] and colours (U-V), (B-V), (R-I), (V-R), (V-I), (V-K),(J-H), (J-K), (I-K), (V-L'), (b-y) and (u-b). These calibrations arebased on a large sample of field and globular cluster stars whichroughly cover spectral types from F0 to K5. Their effectivetemperatures, scaled to direct Teff determinations viareliable angular diameter measurements, were derived by applying theinfrared flux method. The empirical relations have been fitted topolynomials of the form theta_ {eff} = P(colour,[Fe/H]) by using theleast squares method. The precision of the fits ranges from 40 K for(V-K) to 170 K for (J-H). We tabulate intrinsic colours of giant starsin the ranges: 3500 K <= Teff <= 8000 K; -3.0 <=[Fe/H] <= +0.5. We also present the calibration of BC(V) as afunction of log(Teff) and metallicity. Finally, we comparethe resulting scale of temperatures with previous works.
| The effective temperature scale of giant stars (F0-K5). I. The effective temperature determination by means of the IRFM
We have applied the InfraRed Flux Method (IRFM) to a sample ofapproximately 500 giant stars in order to derive their effectivetemperatures with an internal mean accuracy of about 1.5% and a maximumuncertainty in the zero point of the order of 0.9%. For the applicationof the IRFM, we have used a homogeneous grid of theoretical modelatmosphere flux distributions developed by \cite[Kurucz (1993)]{K93}.The atmospheric parameters of the stars roughly cover the ranges: 3500 K<= T_eff <= 8000 K; -3.0 <= [Fe/H] <= +0.5; 0.5 <= log(g) <= 3.5. The monochromatic infrared fluxes at the continuum arebased on recent photometry with errors that satisfy the accuracyrequirements of the work. We have derived the bolometric correction ofgiant stars by using a new calibration which takes the effect ofmetallicity into account. Direct spectroscopic determinations ofmetallicity have been adopted where available, although estimates basedon photometric calibrations have been considered for some stars lackingspectroscopic ones. The adopted infrared absolute flux calibration,based on direct optical measurements of stellar angular diameters, putsthe effective temperatures determined in this work in the same scale asthose obtained by direct methods. We have derived up to fourtemperatures, TJ, TH, TK and T_{L'},for each star using the monochromatic fluxes at different infraredwavelengths in the photometric bands J, H, K and L'. They show goodconsistency over 4000 K, and there is no appreciable trend withwavelength, metallicity and/or temperature. We provide a detaileddescription of the steps followed for the application of the IRFM, aswell as the sources of error and their effect on final temperatures. Wealso provide a comparison of the results with previous work.
| Broad-band JHK(L') photometry of a sample of giants with 0.5 > [Fe/H] > -3
We present the results of a three-year campaign of broad-band photometryin the near-infrared J, H, K and L' bands for a sample of approximately250 giant stars carried out at the Observatorio del Teide (Tenerife,Spain). Transformations of the Telescopio Carlos Sanchez systeminto/from several currently used infrared systems are extended to theredward part of the colour axis. The linearity of our photometric systemin the range -3 mag [Fe/H] >-3. Data of comparable quality previouslypublished have been added to the sample in order to increase thereliability of the relations to be obtained. We also provide mean IRcolours for giant stars according to spectral type.ables 1, 2 and 3 are only available in electronic form via the CDS(anonymous ftp 130.79.128.5 or http://cdsweb.u-strasbg.fr/Abstract.html
| UBVRI Standard Stars at Northern Declinations
Accurate values of V, B--V and U--B are given 123 stars of magnitudesfrom 6 to 11 at high northern declinations. For 36 stars also V--R andR--I color indices are given.
| A study of some stars with circumstellar dust envelopes. I
We present the results of a study of circumstellar dust envelopes of 36stars of early(O-B-A) types in the directions of the associations CasOB1, Cas OB2, Per OB1, and Ori OB1. We determine the absorption at 1640Å, the linear radius of the dust envelopes, the mean value of thecoefficient k, and the masses of the envelopes. They differsignificantly from one another.
| 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.
| UBV photometry of stars whose positions are accurately known. VII
Attention is given to UBV photometry for about 100 equatorial andsouthern stars of the faint extension of the FK5 catalog whichpreviously lacked accurate V photometry. The observations were performedwith the 60-cm Cassegrain telescope of the Royal Swedish Academy ofSciences at La Palma, Canary Islands, during February-March andAugust-September 1992. Extinction coefficients were derived, separatelyfor every night, for the V magnitude as well as for the colors.
| 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.
| UBV photometry of stars whose positions are accurately known. VI
Results are presented from UBV photometric observations of 1000 stars ofthe Bright Star Catalogue and the faint extension of the FK5.Observations were carried out between July 1987 and December 1990 withthe 40-cm Cassegrain telescope of the Kvistaberg Observatory.
| UBV photometry of stars whose positions are accurately known.
Photometric indices V, B-V, and U-B were measured for about 560 stars ofthe AGK3R and NPZT catalogs between BD declinations 11 deg and 23 deg,using the 40-cm Cassegrain telescope of the Kvistaberg Observatory fromApril 1986 to May 1987. The observation procedure and the reductiontechnique were the same as in the earlier papers of this series by Oja(1984, 1985, 1986, and 1987). The mean errors were calculated from theinternal consistency of the data. The accuracy was found to be the sameas for the earlier parts of the survey.
| Narrow-band photometry of late-type stars. II
This paper presents extensive narrow-band photometry in the Uppsalasystem supplementing earlier published mesurements so that data now areavailable for all late-type stars brighter than V = 6.05 and a number ofgalactic cluster members. Numerous UBV and BV measurements are alsopublished. The data are used to determine relations for the predictionof UBV intrinsic colors for late-type stars from the narrow-bandmeasurements. The main purpose of the data is to constitute the basisfor the determination of solar-neighborhood space densities of late-typestars, mainly giants of different kinds; these space densities will becombined with narrow-band data for fainter stars in the north Galacticpole region to yield the decrease of space density with distance fromthe galactic plane for many kinds of late-type stars.
| UBV photometry of stars whose positions are accurately known. IV
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1987A&AS...68..211O&db_key=AST
| UBV photometry of stars whose positions are accurately known. III
UBV photometric observations of 417 stars at BD declination 35-49 degfrom the NPZT(74) catalog of Yasuda et al. (1982) and the AGK3R catalogof Corben (1978), obtained with the 40-cm Cassegrain reflector atKvistaberg Observatory during 1984-1985, are reported. The data arepresented in tables, and the mean errors per observation are given as0.016 mag in V, 0.011 mag in B-V, 0.012 mag in U-B for U less than 10,and 0.026 mag in U-B for U greater than 10.
| Photoelectric photometry of stars near the north Galactic pole. II
UBV photometric observations of about 700 stars near the north Galacticpole, obtained using single-channel photometers on the 40-cm and 60-cmCassegrain telescopes at Kvistaberg Observatory (during 1976-1983) andthe Spanish International Observatory (during 1984), respectively, aspart of a program including the stars to be observed by the Hipparcosspacecraft, are reported. The data are presented in a series of tablesand briefly characterized.
| UBV photometry of stars whose positions are accurately known. II
The present report on the UBV observations of stars with favorableastrometric history gives attention to stars of the BD zones lyingbetween 50 and 54 deg. These observations and their reductions wereperformed from August 1983 to August 1984, as described by Oja (1984).Results are presented as tables for both the standard stars and theprogram stars. Comparisons are conducted between the present Vmagnitudes and those of the NPZT (1982) and AGK3R (1978) catalogs.
| UBV Photometry of Stars whose Positions are Accurately Known
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1984A&AS...57..357O&db_key=AST
| UBV photometry of FK4 and FK4 supplement stars
Traditional UBV filters, together with a photomultiplier, have been usedin 40-m Cassegrain telescope observations of all northern stars of theFK4 catalog and its supplement, which have heretofore lacked V and V-Bmeasurements. The resulting UBV photometry for 320 stars is presented intabular form.
| Observational studies of Cepheids. I - BVRI photometry of bright Cepheids
Over 1,000 differentially determined photoelectric BVRI observations andthe resulting light curves are presented for 24 bright Cepheidsaccessible from Northern Hemisphere observatories. The internalprecision of these data is shown to be better than + or - 0.01 mag, andthe accuracy of transformation to the Johnson BVRI system is nearly asgood.
| Catalog of Indidual Radial Velocities, 0h-12h, Measured by Astronomers of the Mount Wilson Observatory
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJS...19..387A&db_key=AST
| Note on the Cepheid Variable Zeta Geminorum.
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Osservazione e dati astrometrici
| Costellazione: | Gemelli |
| Ascensione retta: | 07h04m04.99s |
| Declinazione: | +20°35'51.1" |
| Magnitudine apparente: | 7.601 |
| Moto proprio RA: | -80.6 |
| Moto proprio Dec: | 39.3 |
| B-T magnitude: | 8.335 |
| V-T magnitude: | 7.662 |
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