|A Large Spectral Class Dependence of the Wilson-Bappu Effect among Luminous Stars|
The striking correlation between Ca II K-line emission width andabsolute visual magnitude has not previously been well calibrated forstars more luminous than giants. From a sample of binary systems fit toisochrones, we find deviations of more than 2 mag, correlated withspectral class, between these binarity Mv values and theWilson-Bappu relation. Additional Mv values derived fromHipparcos parallaxes are used to explore the systematics. The spectralclass dependence vanishes for K-line parameterlogW0<=1.80. Linear spectral class corrections are derivedfor the more luminous stars, with logW0>=2.00, while atable is provided for the transition region. The dispersion from theserelations is about +/-0.6 mag. This recalibration extends thedemonstrated applicability of the Wilson-Bappu technique toMv~=-5 or distance ~20 kpc.
|Research Note Hipparcos photometry: The least variable stars|
The data known as the Hipparcos Photometry obtained with the Hipparcossatellite have been investigated to find those stars which are leastvariable. Such stars are excellent candidates to serve as standards forphotometric systems. Their spectral types suggest in which parts of theHR diagrams stars are most constant. In some cases these values stronglyindicate that previous ground based studies claiming photometricvariability are incorrect or that the level of stellar activity haschanged. Table 2 is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (126.96.36.199) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/367/297
|Two-colour photometry for 9473 components of close Hipparcos double and multiple stars|
Using observations obtained with the Tycho instrument of the ESAHipparcos satellite, a two-colour photometry is produced for componentsof more than 7 000 Hipparcos double and multiple stars with angularseparations 0.1 to 2.5 arcsec. We publish 9473 components of 5173systems with separations above 0.3 arcsec. The majority of them did nothave Tycho photometry in the Hipparcos catalogue. The magnitudes arederived in the Tycho B_T and V_T passbands, similar to the Johnsonpassbands. Photometrically resolved components of the binaries withstatistically significant trigonometric parallaxes can be put on an HRdiagram, the majority of them for the first time. Based on observationsmade with the ESA Hipparcos satellite.
|A Second Catalog of Orbiting Astronomical Observatory 2 Filter Photometry: Ultraviolet Photometry of 614 Stars|
Ultraviolet photometry from the Wisconsin Experiment Package on theOrbiting Astronomical Observatory 2 (OAO 2) is presented for 614 stars.Previously unpublished magnitudes from 12 filter bandpasses withwavelengths ranging from 1330 to 4250 Å have been placed on thewhite dwarf model atmosphere absolute flux scale. The fluxes wereconverted to magnitudes using V=0 for F(V)=3.46x10^-9 ergs cm^-2 s^-1Å^-1, or m_lambda=-2.5logF_lambda-21.15. This second catalogeffectively doubles the amount of OAO 2 photometry available in theliterature and includes many objects too bright to be observed withmodern space observatories.
|Ultraviolet and Optical Studies of Binaries with Luminous Cool Primaries and Hot Companions. V. The Entire IUE Sample|
We have obtained or retrieved IUE spectra for over 100 middle- andlate-type giant and supergiant stars whose spectra indicate the presenceof a hot component earlier than type F2. The hot companions areclassified accurately by temperature class from their far-UV spectra.The interstellar extinction of each system and the relative luminositiesof the components are derived from analysis of the UV and opticalfluxes, using a grid of UV intrinsic colors for hot dwarfs. We find thatthere is fair agreement in general between current UV spectralclassification and ground-based hot component types, in spite of thedifficulties of assigning the latter. There are a few cases in which thecool component optical classifications disagree considerably with thetemperature classes inferred from our analysis of UV and opticalphotometry. The extinction parameter agrees moderately well with otherdeterminations of B-V color excess. Many systems are worthy of furtherstudy especially to establish their spectroscopic orbits. Further workis planned to estimate luminosities of the cool components from the dataherein; in many cases, these luminosities' accuracies should becomparable to or exceed those of the Hipparcos parallaxes.
|A reliable transformation of HIPPARCOS H_p magnitudes into Johnson V and B magnitudes|
A comparison of accurate UBV magnitudes, derived from numerousobservations at Hvar and SkalnatePleso, and of the mean Hipparcos \hpmagnitudes for a number of constant stars showed a very good mutualcorrespondence of these two data sets. Simple transformation formul\ae\are presented which allow calculating Johnson V and B magnitudes fromthe \hp magnitude and known B-V and U-B colours. For constant stars withwell-known values of both colours the accuracy of the transformation isclearly better than 0\m01. At the same time, the transformation is notcritically sensitive to the exact values of B-V and U-B. It isapplicable over a wide range of colours (B-V between -0\m25 and 2\m0)and works well also for reddened stars. However, since it was definedfor stars brighter than about 8\m0 and for reddenings smaller than about1\m0, its application outside these limits should be made with somecaution and further tested. Since the B-V and U-B colours are known forthe majority of brighter stars and since there are many classes ofvariable stars which do change colours only very mildly during theirlight changes (like the majority of Be stars) or for which theinstantaneous colours can be predicted or estimated from existingoptical observations, the transformations presented here may turn out tobe very useful for many researchers who need to combine Hipparcos andoptical photometry into one homogeneous data set.
|The Tokyo PMC catalog 90-93: Catalog of positions of 6649 stars observed in 1990 through 1993 with Tokyo photoelectric meridian circle|
The sixth annual catalog of the Tokyo Photoelectric Meridian Circle(PMC) is presented for 6649 stars which were observed at least two timesin January 1990 through March 1993. The mean positions of the starsobserved are given in the catalog at the corresponding mean epochs ofobservations of individual stars. The coordinates of the catalog arebased on the FK5 system, and referred to the equinox and equator ofJ2000.0. The mean local deviations of the observed positions from theFK5 catalog positions are constructed for the basic FK5 stars to comparewith those of the Tokyo PMC Catalog 89 and preliminary Hipparcos resultsof H30.
|Classification and Identification of IRAS Sources with Low-Resolution Spectra|
IRAS low-resolution spectra were extracted for 11,224 IRAS sources.These spectra were classified into astrophysical classes, based on thepresence of emission and absorption features and on the shape of thecontinuum. Counterparts of these IRAS sources in existing optical andinfrared catalogs are identified, and their optical spectral types arelisted if they are known. The correlations between thephotospheric/optical and circumstellar/infrared classification arediscussed.
|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.
|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.
|CA II H and K measurements made at Mount Wilson Observatory, 1966-1983|
Summaries are presented of the photoelectric measurements of stellar CaII H and K line intensity made at Mount Wilson Observatory during theyears 1966-1983. These results are derived from 65,263 individualobservations of 1296 stars. For each star, for each observing season,the maximum, minimum, mean, and variation of the instrumental H and Kindex 'S' are given, as well as a measurement of the accuracy ofobservation. A total of 3110 seasonal summaries are reported. Factorswhich affect the ability to detect stellar activity variations andaccurately measure their amplitudes, such as the accuracy of the H and Kmeasurements and scattered light contamination, are discussed. Relationsare given which facilitate intercomparison of 'S' values with residualintensities derived from ordinary spectrophotometry, and for convertingmeasurements to absolute fluxes.
|Photoelectric photometry of G-M stars in the Vilnius system|
|Groups of stars with common motion in the Galaxy - Groups of red supergiants of the luminosity classes I and II|
|Mass-losing M supergiants in the solar neighborhood|
A list of the 21 mass-losing red supergiants (20 M type, one G type; Lgreater than 100,000 solar luminosities) within 2.5 kpc of the sun iscompiled. These supergiants are highly evolved descendants ofmain-sequence stars with initial masses larger than 20 solar masses. Thesurface density is between about 1 and 2/sq kpc. As found previously,these stars are much less concentrated toward the Galactic center thanW-R stars, which are also highly evolved massive stars. Although withconsiderable uncertainty, it is estimated that the mass return by the Msupergiants is somewhere between 0.00001 and 0.00003 solar mass/sq kpcyr. In the hemisphere facing the Galactic center there is much less massloss from M supergiants than from W-R stars, but, in the anticenterdirection, the M supergiants return more mass than do the W-R stars. Theduration of the M supergiant phase appears to be between 200,000 and400,000 yr. During this phase, a star of initially at least 20 solarmasses returns perhaps 3-10 solar masses into the interstellar medium.
|Lunar occultations of IRAS point sources, 1991-2000|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1989ApJS...69..651C&db_key=AST
|Stellar integrated fluxes in the wavelength range 380 NM - 900 NM derived from Johnson 13-colour photometry|
Petford et al. (1988) have reported measured integrated fluxes for 216stars with a wide spread of spectral type and luminosity, and mentionedthat a cubic-spline integration over the relevant Johnson 13-colormagnitudes, converted to fluxes using Johnson's calibration, is inexcellent agreement with those measurements. In this paper a list of thefluxes derived in this way, corrected for a small dependence on B-V, isgiven for all the 1215 stars in Johnson's 1975 catalog with completeentries.
|E. W. Fick Observatory stellar radial velocity measurements. I - 1976-1984|
Stellar radial velocity observations made with the large vacuumhigh-dispersion photoelectric radial velocity spectrometer at FickObservatory are reported. This includes nearly 2000 late-type starsobserved during 585 nights. Gradual modifications to this instrumentover its first eight years of operation have reduced the observationalerror for high-quality dip observations to + or - 0.8 km/s.
|Rotation and macroturbulence in bright giants|
Spectral line profiles of 35 F, G, and K bright giants were analyzed toobtain rotation rates, v sin i, and macroturbulence dispersion. Thissample indicates that rotation rates of cool class II giants is lessthan 11 km/s, in contrast with some recent periodicity measurements.Macroturbulence dispersion generally increases with effectivetemperature, but the range of values at a given effective temperature ismuch larger than seen for lower luminosity classes; this is interpretedin terms of red-giant and blue-loop evolution. No evidence is found forangular momentum dissipation on the first crossing of the H-R diagram.
|IRAS catalogues and atlases - Atlas of low-resolution spectra|
Plots of all 5425 spectra in the IRAS catalogue of low-resolutionspectra are presented. The catalogue contains the average spectra ofmost IRAS poiont sources with 12 micron flux densities above 10 Jy.
|Visual multiples. VIII - 1000 MK types|
A total of 1000 new classifications are given for stars brighter than B= 8.0 mag in the Aitken double star catalog. The classificationssupplement 865 classifications obtained in 1981 and 1984. Among thenewly discovered stars are 12 new Ap stars, eight Lambda Bootis stars,one Ba II star, and 60 Am stars. A detailed list of the newclassifications is given.
|The stellar component of the galaxy as seen by the AFGL infrared sky survey|
The noise-limited magnitudes for the Air Force Geophysical Laboratory(AFGL) Infrared Sky Survey have been estimated by direct comparison withground-based observations. Using these limiting magnitudes, 'pruned'versions of the AFGL catalog have been generated. Infrared observationsof all the stellar objects seen at 11, 20, or 27 microns and astatistical sample of the stars seen only at 4 microns are reported.Analysis of the observations leads to estimates of the absolute 4 and 10microns magnitudes and space densities for the two clases of objects.The expected results from the Infrared Astronomical Satellite arereexamined.
|New UBVRI photometry for 900 supergiants|
A description is presented of the results obtained in connection with asystematic program of supergiant photometry on the Johnson UBVRI system.During the eight years after the start of the program, almost 1000 starshave been observed, about 400 three or more times each. The originalselection of stars used the spectral type catalog of Jaschek et al.(1964) to choose supergiants. Since observations were possible from bothChile and Canada, no declination limits were imposed, and no particularselection criteria were imposed other than to eliminate carbon stars.These are so red as to require enormous extrapolations of thetransformation equations.
|Erratum - Errors or Omissions in Star-Identifications in the General Catalogue of Trigonometric Stellar Parallaxes|
|DDO Observations of Southern Stars|
|Lunar occultation summary. III|
Observations of 242 photoelectric lunar occultation events studied atErwin W. Fick Observatory are reported. Approximately one-fourth ofthese are reappearances. From each observation are estimated the minimummagnitude differences between the observed object and possibleundetected companions. Occultation observations are given of 23 starsbrighter than 6th mag, including Alpha Vir, Beta-1 Sco, Mu Gem, Xi-2Sgr, Zeta Tau, Lambda Gem, and Beta Cap.
|Absolute magnitudes of stars from widths of chromospheric CaII emission lines.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976ApJ...205..823W&db_key=AST
|Photoelectric measurements of lunar occultations. VIII|
Photoelectric timings are reported for 276 lunar occultation eventswhich were observed between March 1975 and February 1976. The timings(in UTC) are based on Loran G equipment of a lunar laser-ranging groupor on WWV signals. Angular diameters are determined for HR 5301, HD176124, Chi-1-Orionis, and HR 601. Twenty cases of possible or actualdouble stars, including Beta Capricorni, are noted along with oneprobable triple system (51 Piscium). Several technical and computationaldifficulties encountered in this program are discussed.
|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
|Wavelength dependence of interstellar polarization and ratio of total to selective extinction|
A multichannel polarimeter-photometer which uses dichroic filters toseparate the (UBVR) spectral regions is described. The instrument wasused with a 24-inch rotatable tube telescope for polarimetricobservation of nearby stars. Polarization data for 364 nearby stars aretabulated, together with the wavelength dependence of linear andinterstellar polarization.