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HD 173783


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Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available

New Estimates of the Solar-Neighborhood Massive Star Birthrate and the Galactic Supernova Rate
The birthrate of stars of masses >=10 Msolar is estimatedfrom a sample of just over 400 O3-B2 dwarfs within 1.5 kpc of the Sunand the result extrapolated to estimate the Galactic supernova ratecontributed by such stars. The solar-neighborhood Galactic-plane massivestar birthrate is estimated at ~176 stars kpc-3Myr-1. On the basis of a model in which the Galactic stellardensity distribution comprises a ``disk+central hole'' like that of thedust infrared emission (as proposed by Drimmel and Spergel), theGalactic supernova rate is estimated at probably not less than ~1 normore than ~2 per century and the number of O3-B2 dwarfs within the solarcircle at ~200,000.

A Galactic O Star Catalog
We have produced a catalog of 378 Galactic O stars with accuratespectral classifications that is complete for V<8 but includes manyfainter stars. The catalog provides cross-identifications with othersources; coordinates (obtained in most cases from Tycho-2 data);astrometric distances for 24 of the nearest stars; optical (Tycho-2,Johnson, and Strömgren) and NIR photometry; group membership,runaway character, and multiplicity information; and a Web-based versionwith links to on-line services.

Catalog of Galactic OB Stars
An all-sky catalog of Galactic OB stars has been created by extendingthe Case-Hamburg Galactic plane luminous-stars surveys to include 5500additional objects drawn from the literature. This work brings the totalnumber of known or reasonably suspected OB stars to over 16,000.Companion databases of UBVβ photometry and MK classifications forthese objects include nearly 30,000 and 20,000 entries, respectively.

Observational Evidence of Supershell Blowout in GS 018-04+44: The Scutum Supershell
Emission in the H I 21 cm line has been mapped for a region of theGalaxy that includes two known supershells, GS 018-04+44 and GS034-06+65. We focus on the GS 018-04+44, hereafter referred to as theScutum Supershell, which is an elongated shell about 5 deg in diameterextending to -7 deg below the Galactic plane. The Scutum shell lies at akinematic distance of ~3300 pc, implying a shell diameter of ~290 pcwith a vertical extension of ~400 pc away from the Galactic plane. TheScutum shell contains 6.2x105 Msolar swept intothe walls. We observe that the top of the shell is missing, and asubstantial column of H I rises from the shell walls tob=-11deg, culminating in a large cloud of neutral hydrogen,3.74x104 Msolar, located ~630 pc from the plane.ROSAT data show X-ray emission that closely anticorrelates with the 21cm emission. This emission probably originates from hot gas within theScutum Supershell. After approximately correcting for the foregroundabsorption, we find that the 1.5 keV X-rays peak at the base of theshell, the 0.75 keV emission peaks in the interior and at the top of theshell, and the 0.25 keV emission extends to high latitudes above theshell. The X-ray luminosity is roughly ~5x1036 ergss-1. The Wisconsin Hα Mapper (WHAM) survey shows thepresence of Hα emission that exhibits a morphology similar to thatof the H I. Spectra indicate the presence of ionized hydrogen atvelocities similar to the H I, placing ionized material at the samekinematic distance as the neutral material. IRAS images in the 60 and100 μm wavebands reveal the presence of dust correlated with theneutral hydrogen. Infrared surface brightness indicates an excess in the100 μm emission, which could indicate a molecular hydrogen componentwith a column density of 2.4x1021 cm-2 in thedensest regions of the high-latitude cloud of neutral hydrogen. IUEultraviolet high dispersion spectra of HD 177989 (l=17.89d, b=-11.88d)and HD 175754 (l=16.40d, b=-9.92d) reveal the presence of very strongabsorption by highly ionized gas at a velocity that associates theabsorption with the ejecta of the Scutum Supershell. In the case of HD177989, the high ion column density ratios suggest an origin in aturbulent mixing layer where hot and cool gases mix in the presence ofshear flows. The Hα and X-ray emission suggest that a multitude ofenergetic phenomena exist in this region, providing the necessaryionizing radiation. Indeed, there are multiple supernova remnants, H IIregions, and hot stars, which could all contribute sizeable amounts ofenergy and ionizing radiation. The combination of these data setsindicates observational evidence of a ``blowout'' phenomena whereby hotmaterial produced within the Scutum Supershell has blown through the topof the shell and been pushed to high latitude. Based on observationsfrom the Green Bank 43m radio telescope, the ROSAT All-Sky Survey, theWHAM All-Sky Survey, IRAS, and IUE.

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.

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.

The Diffuse Ionized Interstellar Medium: Structures Resulting from Ionization by O Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1993ApJ...417..579M&db_key=AST

A wide-latitude CO survey of molecular clouds in the northern Milky Way
A wide-latitude, low angular resolution survey of CO along most of thefirst Galactic quadrant and part of the second was undertaken in orderto investigate molecular clouds associated with the Great Rift and thediffuse component of Galactic gamma rays. The main nearby clouds havemasses between a few times 10,000 and a few times 100,000 solar masses,versus a few times a million solar masses for the largest complexeselsewhere. The CO emission in the survey comes nearly equally from localclouds associated with the Great Rift and from distant clouds in theinner arms of the Galaxy 4-7 kpc from the Galactic center. Thehalf-thickness at half-intensity of the local molecular cloud layer isgreater than 50 pc and is estimated to be 75 + or - 25 pc. The resultsstrongly support the notion that all dark nebulae are molecular clouds,and vice-versa.

Two-dimensional spectral classifications for O stars in the southern Milky Way
Spectral classifications in the two-dimensional system are given for 53additional O stars in the southern hemisphere. A number of these starsare members of the interesting clusters NGC 3324, Trumpler 14/16, NGC3603, and NGC 6334, which are discussed in particular. A 4-m H-alphaphotograph of the remarkable nebulosities associated with NGC 6334 isreproduced.

Nitrogen anomalies in O-type stars - A new spectroscopic criterion
A spectroscopic analysis was performed on 95 O-type stars to detectnitrogen overabundance in an investigation of spectroscopic criteria. Itis found that the N III 4514 A line is a good indicator of the abundancevariations of N in O-type stars, and it is suggested that the ONphenomenon is a continuous one rather than a marked discontinuitybetween normal O stars and those showing nitrogen overabundance.Anomalies are investigated for several early O stars, and it isconcluded that mass transfer in close binary systems and high mass lossrates due to stellar winds are the most probable mechanisms to produceON stars.

Finding list and spectral classifications for southern luminous stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976AJ.....81..225M&db_key=AST

Mitteilungen uber Veraenderliche des Bamberger Liste.
Not Available

A catalogue of galactic O stars. The ionization of the low density interstellar medium by runaway stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974RMxAA...1..211C&db_key=AST

A new general O type stars catalogue
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&AS...12..277G&db_key=AST

Etude de la structure galactique a partir d'observations DU calcium interstellaire.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&A....22...69C&db_key=AST

The space distribution and kinematics of supergiants
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970AJ.....75..602H&db_key=AST

An attempt to define luminosity criteria in O stars via narrow-band photoelectric photometry
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970AJ.....75..337L&db_key=AST

Radial Velocities of Distant OB Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1964ApJ...140..162M&db_key=AST

On the Rotation of the Inner Parts of the Galactic System.
Abstract image available at:http://adsabs.harvard.edu/abs/1960ApJ...131..253M

The Law of Interstellar Reddening and Absorption.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1956ApJ...124..367H&db_key=AST

Line Broadening in the Spectra of o- and Early B-Type Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1956ApJ...124..173S&db_key=AST

Studies in Galactic STRUCTURE.II.LUMINOSITY Classification for 1270 Blue Giant Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1955ApJS....2...41M&db_key=AST

Studies in Galactic Structure. I. a Preliminary Determination of the Space Distribution of the Blue Giants.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1953ApJ...118..318M&db_key=AST

A Finding List of O and B Stars of High Luminosity.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1951ApJ...113..141N&db_key=AST

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Pozíciós és asztrometriai adatok

Csillagkép:Pajzs
Rektaszcenzió:18h47m24.18s
Deklináció:-09°18'29.5"
Vizuális fényesség:9.335
RA sajátmozgás:0.4
Dec sajátmozgás:-1.9
B-T magnitude:9.837
V-T magnitude:9.377

Katalógusok és elnevezések:
Megfelelő nevek
HD 1989HD 173783
TYCHO-2 2000TYC 5693-2438-1
USNO-A2.0USNO-A2 0750-14610056
HIPHIP 92198

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