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The association of IRAS sources and 12CO emission in the outer Galaxy
We have revisited the question of the association of CO emission withIRAS sources in the outer Galaxy using data from the FCRAO Outer GalaxySurvey (OGS). The availability of a large-scale high-resolution COsurvey allows us to approach the question of IRAS-CO associations from anew direction - namely we examined all of the IRAS sources within theOGS region for associated molecular material. By investigating theassociation of molecular material with random lines of sight in the OGSregion we were able to construct a quantitative means to judge thelikelihood that any given IRAS-CO association is valid and todisentangle multiple emission components along the line of sight. Thepaper presents a list of all of the IRAS-CO associations in the OGSregion. We show that, within the OGS region, there is a significantincrease ( ~ 22%) in the number of probable star forming regions overprevious targeted CO surveys towards IRAS sources. As a demonstration ofthe utility of the IRAS-CO association table we present the results ofthree brief studies on candidate zone-of-avoidance galaxies with IRAScounterparts, far outer Galaxy CO clouds, and very bright CO clouds withno associated IRAS sources. We find that ~ 25% of such candidate ZOAGsare Galactic objects. We have discovered two new far outer Galaxystar-forming regions, and have discovered six bright molecular cloudsthat we believe are ideal targets for the investigation of the earlieststages of sequential star formation around HII regions. Finally, thispaper provides readers with the necessary data to compare othercatalogued data sets with the OGS data.Tables 1, 2 and A1 are only available in electronic form at the CDS viaanonymous ftp to\ cdsarc.u-strasbg.fr (130.79.128.5) or via\http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/399/1083
| 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
| Stellar and circumstellar evolution of long period variable stars
In a first paper, HIPPARCOS astrometric and kinematic data were used tocalibrate both infrared K and IRAS luminosities at the same time askinematic parameters of Long Period Variable stars (LPVs). Individualestimated absolute magnitudes and a probabilistic assignation togalactic populations were deduced from these calibrations for each LPVof our sample. Here we propose a scenario of simultaneous stellar andcircumstellar evolution according to the galactic populations. Thetransitory states of S and Tc stars allow us to confirm the location ofthe first dredge-up at Mbol=-3.5. There is also evidencesuggesting that a previous enrichment in s-elements from a more evolvedcompanion may accelerate the evolution along the AGB. The possibleevolution to OH LPVs is included in this scenario, and any of thesestars may have a mass at the limit of the capability for a C enrichmentup to C/O > 1. A list of bright massive LPVs with peculiar envelopeand luminosity properties is proposed as Hot Bottom Burning candidates.The He-shell flash star, R Cen, is found to be exceptionally bright andcould become, before leaving the AGB, a C-rich LPV brighter than theusual luminosity limit of carbon stars.
| Long period variable stars: galactic populations and infrared luminosity calibrations
In this paper HIPPARCOS astrometric and kinematic data are used tocalibrate both infrared luminosities and kinematical parameters of LongPeriod Variable stars (LPVs). Individual absolute K and IRAS 12 and 25luminosities of 800 LPVs are determined and made available in electronicform. The estimated mean kinematics is analyzed in terms of galacticpopulations. LPVs are found to belong to galactic populations rangingfrom the thin disk to the extended disk. An age range and a lower limitof the initial mass is given for stars of each population. A differenceof 1.3 mag in K for the upper limit of the Asymptotic Giant Branch isfound between the disk and old disk galactic populations, confirming itsdependence on the mass in the main sequence. LPVs with a thin envelopeare distinguished using the estimated mean IRAS luminosities. The levelof attraction (in the classification sense) of each group for the usualclassifying parameters of LPVs (variability and spectral types) isexamined. Table only 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/374/968 or via ASTRIDdatabase (http://astrid.graal.univ-montp2.fr).
| SiO Masers in Stars in the Inner and Outer Galactic Disk
Observations in the J=1--0, v=1 and v=2 ^{{28}} SiO and v=0 ^{{29}} SiOmaser lines were made towards 97 outer- and 19 inner-disk IRAS sourceswith typical IRAS colors of AGB stars. 21 new ^{{28}} SiO and 1 new^{{29}} SiO maser sources were detected above the 5 sigma level of ~ 1Jy with the Nobeyama 45 m telescope. Collecting all of the observationaldata in SiO J=1--0 maser lines taken with a 45 m telescope, a comparisonis made between the outer-disk, inner-disk, and bulge samples. Thesamples, themselves, align a sequence of mid-infrared color, flux at 12mu m and IRAS variability index. The detection rates are 66%, 51%, and31%, respectively, in the bulge, inner disk, and outer disk. This factis consistent with the tendency of increasing proportion of C-rich starsin the IRAS sample and metallicity gradient with the galactocentricdistance.
| 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.
| 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.
| 61st Name-List of Variable Stars
Not Available
| Listes et classifications d'étoiles M, S, C, trouvées dans divers champs pris aux prismes objectifs à vision directe
Not Available
| The Distribution of the BD M-Type Stars Along the Galactic Equator.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1958ApJ...128..510N&db_key=AST
| Stars with remarkable spectra.
Not Available
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| Takýmyýldýz: | Zincirli Prenses |
| Sað Açýklýk: | 01h37m52.44s |
| Yükselim: | +62°47'48.8" |
| Görünürdeki Parlaklýk: | 8.729 |
| Uzaklýk: | 10000000 parsek |
| özdevim Sað Açýklýk: | 1.8 |
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| B-T magnitude: | 11.723 |
| V-T magnitude: | 8.977 |
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