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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The 74th Special Name-list of Variable Stars
We present the Name-list introducing GCVS names for 3153 variable starsdiscovered by the Hipparcos mission.
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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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Reality Tests of Superclusters in the Young Disk Population
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995AJ....110.2862E&db_key=AST
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The 1.5-1.7 micrometer spectrum of cool stars: Line identifications, indices for spectral classification and the stellar content of the Seyfert galaxy NGC 1068
The first aim of this paper is to determine which lines or narrowmolecular bands in the H-band spectra of cool stars could be of interestfor the classification of K-M stars. For this purpose we present highquality, medium resolution (R approximates 1500) spectra of field stars(mostly K-M giants and supergiants) and compare them with detailedsynthetic spectra computed on the basis of existing model atmospheresfor red giants. The agreement between theoretical and observed spectrais good and virtually all the observed features can be accounted for bylines of (12)CO, (13)CO, OH, Mg, Al, Si, Ca and Fe. We analyze in detailthe relative contribution of these and other species and conclude thatthe feature at 1.62 micrometers which is weak in early K but very strongin late M stars, is mainly due to the CO(6-3) band-head, while that at1.59 micrometers, which is prominent in all stars later than G, isprimarily attributable to silicon up to early M types, while in late Mstars this feature is strongly contaminated by OH lines. We choose thesetwo features as 'spectral classificators' and measure their equivalentwidths in more than 40 G, K, M giants and supergiants. From these datait is found that CO 1.62 in giants increases rapidly and with arelatively small scatter going to later spectral types. Supergiants havedeeper CO(6-3) and display a larger scatter. The (1.62)/(2.29) ratiosteadily increases going to cooler stars but does not vary significantlywith luminosity class. A very useful ratio is (1.62)/(1.59) whichincreases by a large factor from early K to late M stars and couldtherefore be a powerful tool to identify and estimate the averagespectral type of cool stars in complex objects like active galaxynuclei. To demonstrate such a possibility we also present long slitspectra of the Seyfert galaxy NGC 1068 where the equivalent widths ofall stellar features are found to decrease in the central 4 arcsecaround the nucleus but the (1.62)/(1.59) ratio, and hence the averagestellar temperature, does not change significantly. The estimatedaverage spectral type is late-K which is compatible with either an oldand very metallic bulge population or a younger one associated with arecent starburst. These data also show that the non-stellar continuumaccounts for approximately 30% and approximately equal to or greaterthan 80% of the flux at 1.62 and 2.3 micrometers respectively in thecentral 4.4 arcsec. The features around 1.6 micrometers are thus muchless diluted than CO(2, 0) and hence offer advantages for studies of thestellar content in such objects. The non-stellar nuclear emission isvery red and most probably associated with a hot (T approximately equalor greater than 800 K) dust component.
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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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On the (B-V) colors of the bright stars
The possible causes of the dispersion of (B-V) colors of nearby stars inthe Bright Star Catalog are investigated. The distribution of (B-V)colors is presented for the entire range of spectral classes.Explanations for the dispersion in terms of a nonuniform distribution ofinterstellar absorbing material and a variability of metallicity areaddressed. A new statistical model for reddening by interstellar dustclouds is developed. It is concluded that extinction by nonuniforminterstellar matter is an important contribution to the reddening ofnearby stars, and that a part of the dispersion of (B-V) colors of Kand, possibly, M giants may be due to some unidentified variableproperty of those stars.
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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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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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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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The radial velocities of 116 southern red stars
Using a photoelectric speedometer based on the radial velocityspectrometer of Griffin (1967), radial velocities of 116 southern redstars, many of them semi-regular variables, were measured. Theinstrument was placed at the Newtonian focus of the 130-inch (4.2-m)camera of the Coude spectrograph of the Mount Stromlo 74-inch (1.88-m)reflector. The stellar spectrum was focused on a mask 50 mm in length,designed to match the spectrum of the M-giant Beta Pegasi. The inversedispersion was 2.5 angstroms per millimeter in the second order. Thewavelength range used (5338-5449 angstroms) was chosen because it isbetween two TiO bands and so suffers less blanketing in M stars. Resultsare tabulated and compared with standard values.
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Visual and infrared observations of late-type supergiants in the southern sky
Spectral types and photometry ranging from 0.4 to 18 microns are givenfor 54 late-type stars, including 21 supergiants. The infraredobservations of the supergiants confirm the dependence of the strengthof the 10-micron silicate emission feature on the spectral type andluminosity class of the star. The long-wavelength data are also used todetermine the interstellar extinction by fitting an appropriateblackbody to the infrared observations. The deviation from the blackbodyat the shorter wavelengths is then attributed to interstellar absorptionand absorption by TiO. This method is particularly useful when theshort-wavelength photometry is contaminated by a close companion. The Msupergiant AH Sco has excess radiation between 1.5 and 8 microns similarto the NML Tauri-type infrared stars. This excess energy resemblesfree-free emission.
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Infrared Surveys of the Southern Milky way. II. Suspected Supergiant M Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972ApJ...176..623A&db_key=AST
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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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Bright Southern BV-Stars
Not Available
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