Hipparcos red stars in the HpV_T2 and V I_C systems
For Hipparcos M, S, and C spectral type stars, we provide calibratedinstantaneous (epoch) Cousins V - I color indices using newly derivedHpV_T2 photometry. Three new sets of ground-based Cousins V I data havebeen obtained for more than 170 carbon and red M giants. These datasetsin combination with the published sources of V I photometry served toobtain the calibration curves linking Hipparcos/Tycho Hp-V_T2 with theCousins V - I index. In total, 321 carbon stars and 4464 M- and S-typestars have new V - I indices. The standard error of the mean V - I isabout 0.1 mag or better down to Hp~9 although it deteriorates rapidly atfainter magnitudes. These V - I indices can be used to verify thepublished Hipparcos V - I color indices. Thus, we have identified ahandful of new cases where, instead of the real target, a random fieldstar has been observed. A considerable fraction of the DMSA/C and DMSA/Vsolutions for red stars appear not to be warranted. Most likely suchspurious solutions may originate from usage of a heavily biased color inthe astrometric processing.Based on observations from the Hipparcos astrometric satellite operatedby the European Space Agency (ESA 1997).}\fnmsep\thanks{Table 7 is onlyavailable 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/qcat?J/A+A/397/997
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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.
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The FeH Wing-Ford Band in Spectra of M Stars
We study the FeH Wing-Ford band at 9850--10200 A by fitting syntheticspectra to the observations of M stars, employing recent modelatmospheres. On the basis of the spectral synthesis, we analyze thedependence of the band upon atmospheric parameters. FeH lines are a verysensitive surface gravity indicator, being stronger in dwarfs. They arealso sensitive to metallicity. The blending with CN lines, which arestronger in giants, does not affect the response of the Wing-Ford bandto surface gravity at low resolution (or high velocity dispersions),because CN lines, which are spread all along the spectrum, are smearedout at convolutions of FWHM >~ 3 A. We conclude that the Wing-Fordband is a suitable dwarf/giant indicator for the study of compositestellar populations.
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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.
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Asymptotic giant branch stars near the sun
Available red and near-infrared photometry and apparent motions of M, S,and C asymptotic giant branch (AGB) stars in the Bright Star Catalogueare tabulated and discussed. It is shown that the red and near infraredindices normally used for late-type stars are interchangeable except forcarbon stars. The M-type giants are variable with visual amplitudegreater than 0.05 mag. The reddening-free parameter m2 from Genevaphotometry is essentially a temperature parameter for M giants, whilethe reddening-free parameter d is a sensitive detector of blue stellarcompanions. The space density of AGB stars near the sun decreases by afactor of 35 in a temperature range 3800 to 3400 K. Two of the S starsnear the sun were found to have nearly equal space motions and may becomembers of the Arcturus group.
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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
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Lunar occultations of IRAS point sources, 1986-1990
A complete listing is given for objects in the IRAS Point Source Catalogwhich will be occulted by the moon over the course of 1986-1990. A totalof 14,148 ASCII card images is encompassed by the complete listing ofobjects having geocentric events during this period. The resultscontained in this complete listing are illustrated in two of the presenttables for the brightest objects at 12 and 100 micron wavelengths.
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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.
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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.
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Allowance for molecular absorption in the determination of lithium abundance in the atmospheres of M-giants
The equivalent widths of the Li I doublet (6707.76 and 6707.91 A) inM-giant spectra are calculated for different Li abundances on the basisof Tsuji model atmospheres. Allowance is made for the effect of blendinglines of TiO, CN, and ZrO molecular bands. A comparison with observedequivalent widths for 20 M-giants (Merchant, 1967) makes possible animproved determination of lithium abundance in the atmospheres of thesestars. In o(1)Ori and HR 5219 this abundance is 100 times less than inthe solar atmosphere.
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The lithium abundance in the atmospheres of M giants with allowance for molecular absorption
The lithium abundance in the atmospheres of eight giants of the spectralclass K5-M3 has been determined with allowance for molecular absorption.Spectrograms of the stars were obtained using the 2.6-m telescope of theCrimean Astrophysical Observatory with reciprocal dispersion 6 A/mm. Totake into account the molecular absorption, synthetic spectra in theregion 6700-6710 A were calculated by means of Tsuji models (1978). Themodels include all known atomic lines and bands of the molecules TiO,CN, and ZrO. In the atmospheres of six of the eight stars there is adeficit of the lithium abundance; in the atmosphere of 3 Aqr M3 III thelithium abundance has the solar value, while in 29 Cap M3 III a lithiumexcess is found.
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List of 333 variable, microvariable or suspected variable stars detected in the Geneva photometry
A list is presented of 333 stars, excluded from the GCVS and itssupplements, whose probability of variability ranges from high tocertain. The standard deviations observed in the V magnitude togetherwith the known spectral types, however, only allow speculation as to thetype of variable in question pending supplementary observations whichreveal the individual characteristics of these stars.
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The circumstellar envelopes of M giants
The average circumstellar envelopes of 61 red giants of spectral typesM0 through M7 are studied, and information is deduced concerning thevelocity structure in the envelopes as well as the mass-loss mechanism.Positions of red and blue edges of the circumstellar Ca II K4 profileare used to derive information on shell turbulent velocities andvelocity gradients within the envelopes. The results obtained indicatethat: (1) acceleration to a terminal velocity occurs extremely rapidlyor the mass-loss mechanism acts upon Ca III, which recombines only afterthe terminal velocity has been reached; (2) the turbulence must be lessthan 2 km/s in the shells of the M0 giants and should increase to avalue of at least 4 km/s for the M6 giants; (3) the observed broadeningof the K4 profile toward later spectral types must be due at least inpart to the increase in turbulence toward the later types; (4) shellexpansion begins well within the stellar chromospheres; and (5) themass-loss mechanism might involve supersonic winds rather than radiationpressure on grains.
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Lithium abundance in stellar atmospheres
Data on the lithium abundance in the atmospheres of 491 stars arecompiled and reduced to a single system. The lithium abundances of thesestars are shown to differ by more than a factor of 1 million, and thedependence of lithium abundance on spectral type is determined forvarious groups of stars. It is found that cooler stars have lowerlithium abundances than hotter stars and that young stars have higherabundances than old stars. Data on the Li-6/Li-7 isotope ratio in theatmospheres of 30 stars are presented which indicate that Li-6 is notobserved in most cases and that the exceptions comprise magneticvariable stars with Li-6/Li-7 ratios of 0.10 to 2.00. It is concludedthat the observational results as a whole are satisfactorily explainedby the hypothesis that the same high lithium abundance characterized allstars at birth but then decreased in the course of evolution due tointermixing of matter.
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The red giants in the Hyades group
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972PASP...84..406E&db_key=AST
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Stellar kinematics and evolution
Not Available
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Narrow-Band and Broad-Band Photometry of Red Stars. III. Southern Giants
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJ...161..199E&db_key=AST
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The Ratio of Titanium to Zirconium in Late-Type Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJ...161..163B&db_key=AST
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Observational Clues to the Evolution of M Giant Stars
Not Available
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Narrow-and Broad-Band Photometry of Red Stars.IV. Population Separation in Giant Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969ApJ...158..225E&db_key=AST
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- and Broad-Band Photometry of Red Stars. Northern Giants
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1967ApJS...14..307E&db_key=AST
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The Abundance of Lithium in Early M-Type Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1967ApJ...147..587M&db_key=AST
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The absolute magnitudes and parallaxes of 410 stars of type M.
Not Available
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INHABITED SKY
