Young Stars in the Camelopardalis Dust and Molecular Clouds. I. The Cam OB1 Association
The distribution of dust and molecular clouds in the direction ofGalactic longitudes 132--158° and latitudes ± 12\degr\ isinvestigated. The maps of dust distribution in the area were plottedfrom the following surveys: the star counts in the DSS I database byDobashi et al. (2005), the survey of the average infrared color excessesby Froebrich et al. (2007) and the thermal dust emission survey at 100μ m by Schlegel et al. (1998). The distribution of molecular cloudswas taken from the whole sky CO survey by Dame et al. (2001). All thesesurveys show very similar cloud patterns in the area. Using the radialvelocities of CO, the distances to separate clouds are estimated. Arevised list of the Cam OB1 association members contains 43 stars andthe open cluster NGC 1502. 18 young irregular variable and Hαemission stars are identified in the area. All this proves that the starforming process in the Camelopardalis clouds is still in progress.
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Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
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Catalog of Galactic β Cephei Stars
We present an extensive and up-to-date catalog of Galactic β Cepheistars. This catalog is intended to give a comprehensive overview ofobservational characteristics of all known β Cephei stars, coveringinformation until 2004 June. Ninety-three stars could be confirmed to beβ Cephei stars. We use data from more than 250 papers publishedover the last nearly 100 years, and we provide over 45 notes onindividual stars. For some stars we reanalyzed published data orconducted our own analyses. Sixty-one stars were rejected from the finalβ Cephei list, and 77 stars are suspected to be β Cepheistars. A list of critically selected pulsation frequencies for confirmedβ Cephei stars is also presented.We analyze the β Cephei stars as a group, such as the distributionsof their spectral types, projected rotational velocities, radialvelocities, pulsation periods, and Galactic coordinates. We confirm thatthe majority of the β Cephei stars are multiperiodic pulsators. Weshow that, besides two exceptions, the β Cephei stars with highpulsation amplitudes are slow rotators. Those higher amplitude starshave angular rotational velocities in the same range as thehigh-amplitude δ Scuti stars (Prot>~3 days).We construct a theoretical HR diagram that suggests that almost all 93β Cephei stars are main-sequence objects. We discuss theobservational boundaries of β Cephei pulsation and the physicalparameters of the stars. We corroborate that the excited pulsation modesare near to the radial fundamental mode in frequency and we show thatthe mass distribution of the stars peaks at 12 Msolar. Wepoint out that the theoretical instability strip of the β Cepheistars is filled neither at the cool nor at the hot end and attempt toexplain this observation.
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Absolute proper motions of open clusters. I. Observational data
Mean proper motions and parallaxes of 205 open clusters were determinedfrom their member stars found in the Hipparcos Catalogue. 360 clusterswere searched for possible members, excluding nearby clusters withdistances D < 200 pc. Members were selected using ground basedinformation (photometry, radial velocity, proper motion, distance fromthe cluster centre) and information provided by Hipparcos (propermotion, parallax). Altogether 630 certain and 100 possible members werefound. A comparison of the Hipparcos parallaxes with photometricdistances of open clusters shows good agreement. The Hipparcos dataconfirm or reject the membership of several Cepheids in the studiedclusters. Tables 1 and 2 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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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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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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Reddening and polarimetric studies toward IC 1805
Near IR and (V-I) photometry is presented for probable members in thecluster IC 1805. From a color-difference analysis, the ratio of total toselective absorption R(v), is found to be uniform across the cluster andcalculated to be 3.1 + or - 0.1. Assuming a distance modulus to theHyades of 3.3 mag, a distance to IC 1805 of 2.4 + or - 0.1 kpc isobtained by employing several ZAMS fitting calibrations. The resultantC-M diagram contains both MS and ZAMS B type stars, implying thatmassive star formation in the cluster was a continuous process.Photometric and spectroscopic data for foreground stars toward thecluster indicate that at least two-thirds of the reddening of thecluster is due to the general interstellar material (IM). Multicolorpolarimetric measurements are also presented for 24 probable clustermembers and for 49 foreground objects. It is concluded that the visualpolarization across the local galactic spiral arm is 5 percent, and thatthe size distribution of grains within IC 1805 is similar to that in theforeground region. After correcting for foreground IM, the residualintracluster polarization indicates that the cluster may be located neara Parker (1966) magnetic well with field strength similar to that of theforeground IM.
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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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The local system of early type stars - Spatial extent and kinematics
Published uvby and H-beta photometric data and proper motions arecompiled and analyzed to characterize the structure and kinematics ofthe bright early-type O-A0 stars in the solar vicinity, with a focus onthe Gould belt. The selection and calibration techniques are explained,and the data are presented in extensive tables and graphs and discussedin detail. The Gould belt stars of age less than 20 Myr are shown togive belt inclination 19 deg to the Galactic plane and node-lineorientation in the direction of Galactic rotation, while the symmetricaldistribution about the Galactic plane and kinematic properties (purecircular differential rotation) of the belt stars over 60 Myr oldresemble those of fainter nonbelt stars of all ages. The unresolveddiscrepancy between the expansion observed in the youngest nearby starsand the predictions of simple models of expansion from a point isattributed to the inhomogeneous distribution of interstellar matter.
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Catalog of BV magnitudes and spectral classes of 6000 stars
The present catalog, compiled at the Abastumani Observatory, contains BVmagnitudes and spectral classes of about 6000 stars up to V(lim) = 13.0min five circular areas of 18 sq deg located near the salactic-equatorplane. The catalog is intended for star-statistics studies ofstar-formation regions.
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Radial velocities for early type stars in six galactic regions
Coudespectroscopy has been carried out for 353 stars of spectral typesB0-A0 and V magnitudes between 6.5 and 10.8 m, selected in six regions(three northern and three southern) close to the galactic plane at thegalactic longitudes 135, 175, 315 and 350 deg. The radial velocitieswere obtained by cross-correlating each spectrogram with a referencespectrogram giving an internal error of 1.4 km/s.
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Four-color and H-beta photometry for O-A0 type stars in three regions near the galactic equator
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1982A&AS...49..561W&db_key=AST
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A small cluster near IC 1805
A small group of stars near the edge of the IC 1805 (W4) H II region hasbeen studied partly for evidence of a physical association with thenebula. The two brightest stars have pronounced shell spectra andevidence of hydrogen emission lines. A B8 V star with weak Hg lines, twonormal B stars, and four fainter stars in the field were studied. UBV,H-beta, and Stromgren four-color photometry of nine stars yield areddening of E(B - V) = 0.54 m, a distance of 485 pc, and an age of notgreater than 10 to the 7.4th yr. The two shell stars and two normal Bstars fall on the ZAMS but the Hg star is either a multiple orforeground star and the three fainter stars are probably backgroundstars. The group is not associated with the more distant (2200 pc) IC1805.
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Photometric Study of Trapezium-Type Systems
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1979RMxAA...4..287E&db_key=AST
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Mesures d'etoiles doubles faites a Nice.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978A&AS...33..275M&db_key=AST
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The influence of interstellar absorption on measured strengths of the Balmer discontinuity
The definition of the Balmer-discontinuity strength from observationalspectrophotometric data is discussed in relation to detailed results onthe wavenumber dependence of the interstellar absorption. The break inthe interstellar absorption curve at a wavenumber of about 2.33permicrons is found to introduce systematic errors in many currentlydefined strengths of the Balmer discontinuity. The errors should beproportional to the amount of the color excess caused by interstellarabsorption. Using the interstellar absorption curves established byDivan (1954) and by Nandy (1964) theoretical relations are derivedbetween the amount of interstellar absorption and the correspondinginfluence on the Balmer-discontinuity strength. These linear relationsare confirmed through tests on larger sets of observational data. At thesame time the derived relations are useful as correction formulas.
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A spectrophotometric survey of stars along the Milky Way. IV
In the present paper a catalogue of spectrophotometric quantities,spectral types, monochromatic magnitudes and colour equivalents is givenfor all stars brighter than the magnitude m4400 = 10.5 in aregion of the Milky Way in Perseus. No absorption is found for starscloser than about r = 100 pc. The absorbing clouds are situated atdistances closer than 1 kpc and at about 2.5 kpc in the local arm andthe Perseus arm, respectively. The space between the two arms is freefrom absorption. It is also concluded that the Perseus arm continuesbeyond l = 140 deg, containing not only hydrogen gas but also dust to atleast l = 150 deg), while the content of OB stars decreases abruptly atl = 140 deg.
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UBVRI photometry of stars in Trapezium type systems.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977RMxAA...3..133W&db_key=AST
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60th Name-List of Variable Stars
Not Available
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The kinematics of trapezium systems.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974RMxAA...1..101A&db_key=AST
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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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An A-stars concentration in Cas.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974AJ.....79..116P&db_key=AST
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The space density of A stars in a region in Cas.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974AJ.....79..107M&db_key=AST
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Photoelektrische Photometrie von Shell-Sternen
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974A&AS...15..311H&db_key=AST
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Photographic UBV photometry of ten open star clusters in a galactic field at 1 = 135°
Abstract image available at:http://adsabs.harvard.edu/abs/1973A&AS...11....3M
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Near infrared magnitudes of 248 early-type emission-line stars and related objects.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973MNRAS.161..145A&db_key=AST
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The high-luminosity boundary of the beta CEP instability strip.
Abstract image available at:http://adsabs.harvard.edu/abs/1972AJ.....77..381P
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A spectroscopic investigation of visual binaries with B-type primaries.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969AJ.....74.1082M&db_key=AST
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Radio Distances of Gaseous Nebulae
Abstract image available at:http://adsabs.harvard.edu/abs/1968ApJ...154...73H
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Studies of visual double stars. I.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1968AJ.....73..350M&db_key=AST
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INHABITED SKY
