Fundamental parameters of Be stars located in the seismology fields of COROT
In preparation for the COROT space mission, we determined thefundamental parameters (spectral type, temperature, gravity, V sin i) ofthe Be stars observable by COROT in its seismology fields (64 Be stars).We applied a careful and detailed modeling of the stellar spectra,taking into account the veiling caused by the envelope, as well as thegravitational darkening and stellar flattening due to rapid rotation.Evolutionary tracks for fast rotators were used to derive stellar massesand ages. The derived parameters will be used to select Be stars assecondary targets (i.e. observed for 5 consecutive months) and short-runtargets of the COROT mission. Furthermore, we note that the main part ofour stellar sample falls in the second half of the main sequence lifetime, and that in most cases the luminosity class of Be stars isinaccurate in characterizing their evolutionary status.
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Far Ultraviolet Spectroscopic Explorer observations of high-velocity gas associated with the Monoceros Loop SNR
We present Far Ultraviolet Spectroscopic Explorer (FUSE) observations ofhigh-velocity gas (VLSR = +65 km s-1) seen towardsthe star HD 47240 which lies just behind the Monoceros Loop SupernovaRemnant at a distance of ~ 1800 pc. This high-velocity absorptionfeature is detected in the far ultraviolet lines of O I, Ar I, N I, C I,Fe II and P II, in addition to being detected at visible wavelengths inNa I and Ca II and at near ultraviolet wavelengths in Mg II, Mg I, S II,O I, Si II, C II*, Al II and Fe II. High-velocity interstellar gas hasnot been detected in the high-ionization (high-temperature) species of OVI, C IV and Si IV. Gas phase abundances relative to that of sulphur forthis high velocity feature have been derived. The refractory elements ofFe, Si and Al are all less depleted than that normally found for colddisk gas in the interstellar medium, with a pattern of relativeabundance more similar to that of warm interstellar disk gas. However,the elements of N, O, and Ar show an opposite pattern of relativedepletion in which their apparent elemental deficiency may be attributedto ionization effects, as also found for high-velocity gas associatedwith the Vela SNR by Jenkins et al. (\cite{jenkins98}). The lack ofdetection of high-ionization gas at high velocity suggests that theMonoceros Loop remnant is more evolved than other remnants such as theVela SNR or Cygnus Loop, and that an age of 30 000-150 000 years seemsappropriate.
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Statistical analysis of intrinsic polarization, IR excess and projected rotational velocity distributions of classical Be stars
We present the results of statistical analyses of a sample of 627 Bestars. The parameters of intrinsic polarization (p*),projected rotational velocity (v sin i), and near IR excesses have beeninvestigated. The values of p* have been estimated for a muchlarger and more representative sample of Be stars (~490 objects) thanpreviously. We have confirmed that most Be stars of early spectral typehave statistically larger values of polarization and IR excesses incomparison with the late spectral type stars. It is found that thedistributions of p* diverge considerably for the differentspectral subgroups. In contrast to late spectral types (B5-B9.5), thedistribution of p* for B0-B2 stars does not peak at the valuep*=0%. Statistically significant differences in the meanprojected rotational velocities (/line{vsin i}) are found for differentspectral subgroups of Be stars in the sense that late spectral typestars (V luminosity class) generally rotate faster than early types, inagreement with previously published results. This behaviour is, however,not obvious for the III-IV luminosity class stars. Nevertheless, thecalculated values of the ratio vt/vc of the truerotational velocity, vt, to the critical velocity forbreak-up, vc, is larger for late spectral type stars of allluminosity classes. Thus, late spectral type stars appear to rotatecloser to their break-up rotational velocity. The distribution of nearIR excesses for early spectral subgroups is bi-modal, the position ofthe second peak displaying a maximum value E(V-L)~ 1 . m 3for O-B1.5 stars, decreasing to E(V-L)~0. m8 for intermediatespectral types (B3-B5). It is shown that bi-modality disappears for latespectral types (B6-B9.5). No correlations were found betweenp* and near IR excesses and between E(V-L) and vsin i for thedifferent subgroups of Be stars. In contrast to near IR excesses, arelation between p* and far IR excesses at 12 mu m is clearlyseen. A clear relation between p* and vsin i (as well asbetween p* and /line{vsin i}/vc) is found by thefact that plots of these parameters are bounded by a ``triangular"distribution of p*: vsin i, with a decrease of p*towards very small and very large vsin i (and /line{vsini}/vc) values. The latter behaviour can be understood in thecontext of a larger oblateness of circumstellar disks for the stars witha rapid rotation. From the analysis of correlations between differentobservational parameters we conclude that circumstellar envelopes forthe majority of Be stars are optically thin disks with the range of thehalf-opening angle of 10degr
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Catalogue of H-alpha emission stars in the Northern Milky Way
The ``Catalogue of Stars in the Northern Milky Way Having H-alpha inEmission" appears in Abhandlungen aus der Hamburger Sternwarte, Band XIin the year 1997. It contains 4174 stars, range {32degr <= l() II< 214degr , -10degr < b() II < +10degr } having the Hαline in emission. HBH stars and stars of further 99 lists taken from theliterature till the end of 1994 were included in the catalogue. We givethe cross-identification of stars from all lists used. The catalogue isalso available in the Centre de Données, Strasbourg ftp130.79.128.5 or http://cdsweb.u-strasbg.fr and at the HamburgObservatory via internet.
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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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Catalogue of stars in the northern Milky Way having H-alpha in emission
Not Available
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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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Decameter wavelength observations of the Rosette Nebula and the Monoceros loop supernova remnant
In view of the maps here presented on the basis of 20.6, 25.6, and 30.9MHz observations of a field containing the Rosette Nebula and theMonoceros Loop SNR, radiation from the SNR appears to be absorbed by theRosette Nebula; this suggests that the SNR is located behind the H IIregion, but still within the Mon OB2 association, at a distance of about1.6 kpc. A mean electron temperature of 8700 + or - 1300 K is determinedfor the Rosette Nebula, which is in reasonable agreement with resultsobtained by other methods, together with a nonthermal emissivityaveraged along the line of sight to the Rosette of 16.5 + or - 3 K/pc at20.6 MHz.
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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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The Monoceros Loop: A supernova remnant interacting with the Rosette Nebulae
The UV spectra of HD 47240, a B1Ib star located behind the MonocerosLoop, was used to analyze the distribution and motion of interstellarmatter in this region and to investigate the expanding nebula. Resultsreveal a galactic component that is related to the interstellar mediumpresent in the galaxy between the Sun and the target star; a fast movingcomponent that is linked to the receding part of the Monoceros Loopsupernova remnant; and a peculiar component which is detected only inhighly ionized species and has a rather high ratio CIV/SiIV. Comparisonwith other observations indicates that the Monoceros Loop is inside theMon OB2 association and interacts directly with the nearby RosetteNebula. This interaction is observed through the peculiar component. Itis shown that the Loop is a supernova which exploded in a medium withdensity one tenth the standard.
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High-velocity gas in the Monoceros loop.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977PASP...89..626C&db_key=AST
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The value of R in Monoceros
Recent photometric and spectroscopic observations are used inconjunction with other data for early-type stars in northern Monocerosin order to investigate the local value of R (the ratio of total toselective extinction). From a variable-extinction analysis, it isconcluded that a ratio of approximately 3.2 is appropriate for thegeneral interstellar extinction in this region and that there is noevidence here for the existence of local anomalies. The two majorassociations Mon OB 1 and Mon OB 2 are clearly delineated and are foundto exhibit properties typical of such young stellar groups. Derivedproperties for a few interesting stars are presented.
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High-velocity gas in supernova remnants. III - The Monoceros Loop
The paper reports on observations of interstellar absorption lines inthe spectra of 25 stars near the Monoceros Loop. An absorption featurewith a velocity of +69 km/s (with respect to the local standard of rest)is found in the spectrum of HD 47240, and an absorption feature with avelocity of -31 km/s is found in the spectrum of HD 47359. Thesefeatures are attributed to high-velocity clouds accelerated by thesupernova explosion that produced the Loop. Three low-velocity Ca IIfeatures are observed throughout the region. A mean expansion velocityof 50 km/s is derived for the Loop and shown to be in excellentagreement with that obtained previously from H-alpha interferograms. Thedata are compared with those for other supernova remnants, and it isfound that the Monoceros Loop appears to be an extension of the agesequence extending from Vela XYZ through the Cygnus Loop and Shajn 147.It is concluded that the age of the Monoceros Loop is greater than150,000 years.
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The open cluster Collinder 107 and a Stellar Ring in Monoceros
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&AS...10..365I&db_key=AST
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Observations of interstellar reddening V,
Not Available
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Luminous Stars in the Northern Milky Way
Not Available
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Catalogue of stellar spectra classified in the Morgan-Keenan system
Not Available
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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
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Polarization in NGC2244
Not Available
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Cepheids and galactic structure.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1958AJ.....63..492V&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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General Catalogue of Stellar Radial Velocities
Not Available
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Polarization of Stellar Radiation. III. The Polarization of 841 Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1951ApJ...114..241H&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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Second Supplement to the Mount Wilson 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?1949ApJ...110..387M&db_key=AST
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