Interstellar NaI and CaII absorption observed towards the Cygnus Loop SNR
We present high resolution spectra (R ~ 5 km s-1) of theinterstellar NaI and CaII absorption lines observed towards 9 early-typestars with distances ranging from 250 to 2300 pc in the line-of-sighttowards the Cygnus Loop Supernova Remnant (SNR). All but one of theseabsorption profiles can be fit using a combination of one or more ofthree absorption components with average best-fit (lsr) velocities ofV1 = + 0.8 km s-1, V2 = +9.0 kms-1 and V3 = +19.7 km s-1. Anadditional velocity component at V4 = +29.7 km s-1is required in order to fit the NaI profile recorded towards the star HD198946, whose distance of 794 pc places it well in excess of the nominal440 pc distance to the SNR. The NaI/CaII column density ratios for thethree higher velocity components are typically <1.0, which aresimilar to values found for high-velocity gas components detectedtowards other evolved SNRs. Even though we have detected the threehigher velocity components solely along the sight-lines towards starswith distance estimates greater than that of the Cygnus Loop, we areunable to definitely associate these components with an interactionbetween the expansion of the SN shock wave and the ambient interstellarmedium. We suggest a more likely origin for these absorption componentsis that of an old pre-cursor SN neutral gas shell, within whoseinterstellar cavity the Cygnus Loop supernova explosion occured some 20000 years ago.
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UBV beta Database for Case-Hamburg Northern and Southern Luminous Stars
A database of photoelectric UBV beta photometry for stars listed in theCase-Hamburg northern and southern Milky Way luminous stars surveys hasbeen compiled from the original research literature. Consisting of over16,000 observations of some 7300 stars from over 500 sources, thisdatabase constitutes the most complete compilation of such photometryavailable for intrinsically luminous stars around the Galactic plane.Over 5000 stars listed in the Case-Hamburg surveys still lackfundamental photometric data.
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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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Anomalous Proper-Motions in the Cygnus Super Bubble Region
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1993A&AS..101...37C&db_key=AST
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An Einstein Observatory SAO-based catalog of B-type stars
About 4000 X-ray images obtained with the Einstein Observatory are usedto measure the 0.16-4.0 keV emission from 1545 B-type SAO stars fallingin the about 10 percent of the sky surveyed with the IPC. Seventy-fourdetected X-ray sources with B-type stars are identified, and it isestimated that no more than 15 can be misidentified. Upper limits to theX-ray emission of the remaining stars are presented. In addition tosummarizing the X-ray measurements and giving other relevant opticaldata, the present extensive catalog discusses the reduction process andanalyzes selection effects associated with both SAO catalog completenessand IPC target selection procedures. It is concluded that X-rayemission, at the level of Lx not less than 10 exp 30 ergs/s, is quitecommon in B stars of early spectral types (B0-B3), regardless ofluminosity class, but that emission, at the same level, becomes lesscommon, or nonexistent, in later B-type stars.
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The structure and dynamics of evolved supernova remnants Shock-heated dust in the Cygnus Loop
Observations of shock-heated dust in the Cygnus Loop made with IRAS at12, 25, 60, and 100 microns are presented and analyzed. A bright shellis observed, coincident with the optical nebulosity and X-ray emission.Beam reconstruction and background removal techniques are employed tomap the preshock density distribution within the shell. Emissioncharacteristics are well described by current models of shock-heateddust if account is taken of the effects of an incomplete cooling layerand the presence of recombined gas. A revised distance estimate (D = 460+ or - 160 pc) is obtained, and the environment of the SNR is discussed.The evidence presented here as well as other recent observations verystrongly suggest the existence of a high-density shell which predatesthe SNR. Optical observations of radially structured ionization zonesand the apparent energy-diameter relationship for SNR suggest that thisis a general phenomenon.
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Catalog of O-B stars observed with Tokyo Meridian Circle
A catalog of the O-B stars, selected from 'Blaauw-Parenago' list andRubin's catalog, has been compiled on the FK4 system by the observationsmade with Gautier 8-inch Meridian Circle at the Tokyo AstronomicalObservatory during the period, 1971 to 1979. It contains 1059 stars andwas compiled for the future establishment of high precision propermotions of O-B stars.
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UBV photometry of 180 early-type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974PASP...86..795G&db_key=AST
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Some Spectroscopic Characteristics of the OB Stars: an Investigation of the Space Distribution of Certain OB Stars and the Reference Frame of the Classification
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971ApJS...23..257W&db_key=AST
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Spectral Classifications of 239 Early-Type Stars
Not Available
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Radial Velocities and Spectral Types for Fourteen Stars
Not Available
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Troisième catalogue de l'Observatoire de Besançon comprenant 764 étoiles réduites à 1950, 0 sans mouvement propre et 326 étoiles FK3 pour l'époque moyenne d'observation
Not Available
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INHABITED SKY
