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HD 161306


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

The infrared void in the Lupus dark clouds revisited: a polarimetric approach
The results of B-band CCD imaging linear polarimetry obtained for starsfrom the Hipparcos catalogue are used to re-examine the distribution ofthe local interstellar medium towards the IRAS 100-μm emission voidin the Lupus dark clouds. The analysis of the obtainedparallax-polarization diagram assigns to the dark cloud Lupus1 adistance between 130 and 150pc and assures the existence of a low columndensity region coincident with the observed infrared void. Moreover,there are clear indications of the existence of absorbing material atdistances closer than 60-100pc, which may be associated with theinterface boundary between the Local Bubble and its neighbourhood LoopIsuperbubble.

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.

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.

Five-colour photometry of OB-stars in the Southern Hemisphere
Observations of OB-stars, made in 1959 and 1960 at the Leiden SouthernStation near Hartebeespoortdam, South Africa, with the VBLUW photometerattached to the 90 cm light-collector, are given in this paper. They arecompared with photometry obtained by \cite[Graham (1968),]{gra68}\cite[Walraven & Walraven (1977),]{wal77} \cite[Lub & Pel(1977)]{lub77} and \cite[Van Genderen et al. (1984).]{gen84} Formulaefor the transformation of the present observations to those of\cite[Walraven & Walraven (1977)]{wal77} and \cite[Lub & Pel(1977)]{lub77} are given. Table 4 is only available in electronic format the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) orvia http://cdsweb.u-strasbg.fr/Abstract.html

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.

BVR Photometry of Northern Galactic Plane Luminous Stars
CCD-based BVR photometry of 90 stars listed in Volumes II, III, and IVof the Case-Hamburg Catalog of Luminous Stars in the Northern Milky Wayis reported. This research was performed at the Lowell Observatory 31inch telescope, which, under an agreement with Northern ArizonaUniversity and the NURO Consortium, is operated 60% of the time as theNational Undergraduate Research Observatory.

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.

Spectropolarimetry of the Bipolar Planetary Nebula M2-9
We present optical spectropolarimetry of the young bipolar planetarynebula M2-9. The goal of these observations is to determined theorigin of the knots or brightness enhancements seen in the lobes ofM2-9. The line spectra of the lobes of M2-9 are composed of twocomponents, one that is produced locally in the lobes and one that isscattered from deep in the nebula. The presence of this scatteredradiation means that the total flux line ratios do not accuratelydescribe the local conditions in the lobes. We have obtainedspectropolarimetric data of the N2 and S2 knots and the adjacentnebula, and we use our data to separate the scattered and unscatteredemission-line components.The spectrum of the core of M2-9 exhibits broad H? emissionlines. In our high-resolution spectra we observe a broad wing on thescattered H? line profile at all of the positions in the northlobe. This confirms that the scattered line emission originates in thecore. In addition, we calculate the outflow velocity of thescatterers, ?15 km s-1, based on the observedwavelength shift between the H? peak in scattered andunscattered flux.Using the unscattered spectra, we derive the local line ratios as afunction of position in the north and south lobes. The degree ofionization of the spectra decreases in the off-knot regions. Wemeasure the gas temperature as a function of position and find that itis approximately constant across the lobes. This result rules out thesimple recombination tail model proposed by Goodrich for the origin ofthe knots. We suggest instead that the off-knot positions are ionizedby a UV spectrum that is attenuated by material between the off-knotpositions and the central UV source. We have used the photoionizationcode CLOUDY to test this idea and find that attenuation effects alonecannot accurately reproduce the observed unscattered line ratios. Toaccurately model the observed line ratios in the knots, we require thepresence of both high (? 105 cm-3) and low(? 103 cm-3) density components. For theoff-knot positions both attenuation effects and multiple densitycomponents are necessary to reproduce the observed line ratios.We modify the recombination tail model proposed by Goodrich to explainthe origin of the knots in M2-9. We propose, as did Goodrich, that atdiscrete north-south levels, the lobes of M2-9 contain "rings" ofhigher density material. The UV source illuminates a section of thelobe, causing these rings of material to glow, producing the knots andexplaining and naturally leading to their "fixed" north-southpositions. Obscuring material near the star keeps one side of thelobe from being illuminated by the full force of UV source, thusexplaining the lower excitation off-knot spectra. This model canexplain why the knots appear to move only in the east-west plane,while remaining fixed in the north-south direction. In addition, itexplains why the observed spectra in the off-knot regions are lowerexcitation than the knot spectra.

SAO stars with infrared excess in the IRAS Point Source Catalog
We have undertaken a search for SAO stars with infrared excess in theIRAS Point Source Catalog. In contrast to previous searches, the entireIRAS (12)-(25)-(60) color-color diagram was used. This selection yieldeda sample of 462 stars, of which a significant number are stars withcircumstellar material. The stars selected can be identified aspre-main-sequence stars, Be stars, protoplanetary systems, post-AGBstars, etc. A number of objects are (visual) binary stars.Characteristic temperatures and IR excesses are calculated and theirrelations to spectral type are investigated.

Toward selection of intermediate-magnitude polarization standards
The Minipol optical polarimeter with a V-band filter was used to observe16 summer intermediate-magnitude (mB = about 9) stars from the survey ofMathewson and Ford (1970). These stars were chosen to span polarizationpercentages from zero to almost 6 percent and to cover a large range ofpolarization position angles. The primary reason for reobserving thesestars was to determine their V-band polarization properties and toidentify polarization variables, which are unsuitable standards. TheMinipol observations showed that 12 of the stars had V-bandpolarizations that were very similar to the Mathewson and Ford B-bandvalues. One star had a significantly different polarization positionangle and two had significantly different percentage polarizations. Onestar, HD 161306, was wildly different in both percentage polarizationand position angle.

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.

Distances, reddenings and distribution of emission B-stars in the galactic centre region /l/ not greater than 45 deg
The distribution of Be stars in the region surrounding the Galacticcenter and their correlation to the spiral structure of the Galaxy hasbeen studied. The results are discussed in terms of reddenings anddistances of these stars. Data are presented on the Galacticcoordinates, colors, interstellar color excesses, reddening-freemagnitudes and colors, adopted absolute magnitudes, distances in kpc,distances from the Galactic plane, and MK spectral type.

Photometric observations of emission B-stars in the southern Milky Way
In order to study the distribution of Be stars and their correlation tothe local spiral structure of the Galaxy photoelectric UBV photometrywas carried out for a total of 488 Be stars located in the southernMilky Way between galactic longitudes 315 and 45 deg. UBV magnitudes arepresented for these stars.

A Catalogue of Be-Stars
Not Available

Wavelength dependence of interstellar polarization and ratio of total to selective extinction
A multichannel polarimeter-photometer which uses dichroic filters toseparate the (UBVR) spectral regions is described. The instrument wasused with a 24-inch rotatable tube telescope for polarimetricobservation of nearby stars. Polarization data for 364 nearby stars aretabulated, together with the wavelength dependence of linear andinterstellar polarization.

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

UBV photometry of southern early-type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974MNRAS.168..451H&db_key=AST

Be stars and galactic rotation.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1968AJ.....73..338C&db_key=AST

Spiral arms
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1967MNRAS.137..337D&db_key=AST

Interstellar line velocities in the southern Milky Way (1966).
Not Available

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

Catalogue of stellar spectra classified in the Morgan-Keenan system
Not Available

Radial velocities of southern B stars determined at the Radcliffe Observatory (paper III).
Not Available

Luminous Stars in the Northern Milky Way
Not Available

Kinematic studies of early-type stars. I. Photometric survey, space motions, and comparison with radio observations.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1962AJ.....67..491R&db_key=AST

A Spectroscopic and Photometric Study of the be Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1958ApJ...128..207M&db_key=AST

Interstellar Polarization in the Southern Milky way.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1956ApJ...124...43V&db_key=AST

General Catalogue of Stellar Radial Velocities
Not Available

Catalogue and Bibliography of Stars of Classes B and a whose Spectra have Bright Hydrogen Lines
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1933ApJ....78...87M&db_key=AST

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Observation and Astrometry data

Constellation:Ophiucus
Right ascension:17h45m07.70s
Declination:-09°48'54.5"
Apparent magnitude:8.303
Distance:354.61 parsecs
Proper motion RA:-0.4
Proper motion Dec:-9.4
B-T magnitude:8.923
V-T magnitude:8.355

Catalogs and designations:
Proper Names   (Edit)
HD 1989HD 161306
TYCHO-2 2000TYC 5665-535-1
USNO-A2.0USNO-A2 0750-11895622
HIPHIP 86884

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