Diffuse interstellar bands in RAVE survey spectra
We have used spectra of hot stars from the RAVE Survey in order toinvestigate the visibility and properties of five diffuse interstellarbands previously reported in the literature. The RAVE spectroscopicsurvey for Galactic structure and kinematics records CCD spectracovering the 8400-8800 Å wavelength region at 7500 resolvingpower. The spectra are obtained with the UK Schmidt at the AAO, equippedwith the 6dF multi-fiber positioner. The DIB at 8620.4 Å is by farthe strongest and cleanest of all DIBs occurring within the RAVEwavelength range, with no interference by underlying absorption stellarlines in hot stars. It correlates so tightly with reddening that itturns out to be a reliable tool to measure it, following the relationEB-V = 2.72 (± 0.03)× EW~(Å), validthroughout the general interstellar medium of our Galaxy. The presenceof a DIB at 8648 Å is confirmed. Its intensity appears unrelatedto reddening, in agreement with scanty and preliminary reports availablein the literature, and its measurability is strongly compromised bysevere blending with underlying stellar He I doublet at 8649 Å.The two weak DIBs at 8531 and 8572 Å do not appear real and shouldactually be blends of underlying stellar lines. The very weak DIB at8439 Å cannot be resolved within the profile of the much strongerunderlying hydrogen Paschen 18 stellar line.Table 1 is only available in electronic form at http://www.aanda.org
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Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
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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.
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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.
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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.
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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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A Radial Velocity Database for Stephenson-Sanduleak Southern Luminous Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....113..823R&db_key=AST
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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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A spectroscopic database for Stephenson-Sanduleak Southern Luminous Stars
A database of published spectral classifications for objects in theStepenson-Sanduleak Luminous Stars in the Southern Milky Way catalog hasbeen compiled from the literature. A total of 6182 classifications for2562 stars from 139 sources are incorporated.
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Uvby-beta observations of 528 type B stars with V between the 8th and 9th magnitude
The paper presents uvby-beta measurements of 528 type B stars selectedfrom the SAO Catalog on the basis of two criteria: the spectral types inthe range B3-B5 and mV between the 8th and the 9th magnitude. Reddeningindependent (c1) values are estimated from the spectral classificationand compared to the observed values. No systematic trend with observed(b-y), H-beta, or spectral type appears to be present, but the range of(c1) residuals is surprisingly large. A rather large part of the starshas small beta values, smaller than for the BIa supergiants. Only twoare classified as O stars and most of them have the suffix e, ne, ornne. Most beta values for the O type stars are slightly above the upperlimit of 2.585 m.
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Photoelectric photometry of OB stars in the Vilnius system
Not Available
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The initial mass function for massive stars
A machine readable catalog of over 750 galactic O stars with publishedphotometry, spectral types, and luminosity classes has been compiled.The catalog is probably complete to a distance of about 2.5 kpc. Fromthis volume-limited data, the initial mass function (IMF) for stars moremassive than 20 solar masses has been derived. This IMF differs fromthat of Miller and Scalo (1979) and of Lequeux (1979), in havingproportionately more O type stars and not as steep a fall-off in numberof stars with increasing mass. Dividing the sample into stars inside andoutside the solar circle, a substantial difference in the IMF of themost massive stars is found. There are proportionally more toward thegalactic center. This gradient in the IMF may be related to the observedspace density of Wolf-Rayet stars, which are descendants of O typestars.
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Studies of luminous stars in nearby galaxies. I. Supergiants and O stars in the Milky Way.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978ApJS...38..309H&db_key=AST
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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
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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
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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
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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
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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
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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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INHABITED SKY
