V505 Mon - An early-type binary with a disk
New spectra of the eclipsing binary V505 Mon (usually classified as B5Ib) were obtained in the optical and UV regions. Only spectral lines ofone component are visible, with K = 93 km s-1. According toarguments based on the extent of the disk the mass ratio might be about0.30. The star with the visible spectral lines would then have a mass of2.3, the other component of 7.7 Msun, i.e. their supergiantnature can be ruled out. The distance to the system appears to be about1 kpc. Together with published photometric data, the spectroscopyprovides clear evidence for the presence of a disk around the secondarycomponent. The profiles of the C II 1335/6 doublet lines are used toderive the rotational velocity of the disk. The structure of the diskcan be characterized by a central ionized zone surrounded by neutralouter parts. Additional matter of cloudy nature has to be present, andboth components are embedded in an extended atmosphere. Abundance ofcarbon was found to be very low. Similarity with some othernon-eclipsing binaries is discussed. Based on observations collected atthe European Southern Observatory, La Silla, Chile, and at theGerman-Spanish Observatory, Calar Alto, Spain.
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A Search for High-Velocity Be Stars
We present an analysis of the kinematics of Be stars based uponHipparcos proper motions and published radial velocities. We findapproximately 23 of the 344 stars in our sample have peculiar spacemotions greater than 40 km s-1 and up to 102 kms-1. We argue that these high-velocity stars are the resultof either a supernova that disrupted a binary or ejection by closeencounters of binaries in young clusters. Be stars spun up by binarymass transfer will appear as high-velocity objects if there wassignificant mass loss during the supernova explosion of the initiallymore massive star, but the generally moderate peculiar velocities of BeX-ray binaries indicate that the progenitors lose most of their massprior to the supernova (in accordance with model predictions). Binaryformation models for Be stars predict that most systems bypass thesupernova stage (and do not receive runaway velocities) to createultimately Be+white dwarf binaries. The fraction of Be stars spun up bybinary mass transfer remains unknown, since the post-mass transfercompanions are difficult to detect.
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The 74th Special Name-list of Variable Stars
We present the Name-list introducing GCVS names for 3153 variable starsdiscovered by the Hipparcos mission.
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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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Investigation of the variability of bright Be stars using HIPPARCOS photometry
The high accuracy and the homogeneity of Hipparcos data for bright starshave allowed us to quantify the degree of variability of Be stars. Thisdegree has been found to be highly dependent on the temperature of thestar. Rapid variability is the main feature of the 86% of early Be andless than 20% of late Be stars taking into account the limit ofdetection considered. In addition to Be stars reported in the Hipparcoscatalogue (ESA 1997) as short-period variables, we have been able toenlarge the number of detections as well as to confirm periodspreviously determined. Be stars that show larger amplitude rapidvariations are proposed as candidates for a search of multiperiodicityi.e. as non-radial pulsators. We have also searched for the presence ofoutbursts and fading events in the Hipparcos data. Outbursts have beenfrequently and preferentially detected in early Be stars with rather lowto moderate v sini while fading events seem to be more conspicuous instars with higher v sini. Mid-term and long-term variations have alsobeen investigated. Several stars have shown some evidence of temporaryquasi-periodic oscillations ranging between 10 and 200 days. Finallyinformation concerning long-term variations is reported. Cycles shorterthan or equal to the Hipparcos mission have mainly been detected instars earlier than B6. Long-term time scales of late Be stars areconfirmed to be longer by far. Tables 1 and 2 are only available inelectronic form at CDS via ftp to cdsarc.u-strasbg.fr (130.79.128.5) orvia http://cdsweb.u-strasbg.fr/Abstract.html
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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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Radio continuum emission from stars: a catalogue update.
An updated version of my catalogue of radio stars is presented. Somestatistics and availability are discussed.
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The orbital parameters and the IUE spectrum of the single-lined spectroscopic binary HD 698
IUE observations of the spectroscopic binary HD 698 show that itscontinuous spectrum corresponds to that of a B5 III-II object and that,even in the ultraviolet, the object is single-lined. The spectrumdisplays several sets of lines, all in absorption, where features can bedistinguished that partake of the orbital motion of the B5 component,lines that suggest the existence of nonthermal sources of energy, andlines that form at the boundary of the circumstellar envelope, part ofthem being of purely interstellar origin. The circumbinary envelopeappears to expand and then starts decelerating before the layer isreached where the resonance doublet of Si IV originates. The 'discreteabsorptions' that are characteristics of the spectra of early-type starsare present in the spectrum. New values of the orbital period and of therest of the orbital parameters are determined on the basis of all theavailable ground-based data.
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Groups of stars with common motion in the Galaxy. Groups of O and B stars
Not Available
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LkH-alpha 198 and V 376 Cassiopeiae - Speckle interferometric and polarimetric observations of circumstellar dust
The circumstellar material close to the stellar sources is investigated,and its distribution and its relations to the general optical appearanceand the orientation of the molecular outflow are determined. Speckleobservations were carried out with a near-infrared speckleinterferometer between September 1986 and October 1989. LkH-alpha 198shows a complicated structure without clear alignment, and this is alsotrue on subarcsec (less than 1000 AU) scales. V 376 Cas appears to be abipolar nebula, seen nearly edge-on, oriented at position angle 120 deg.The orientations of LkH-alpha 198 and V 376 show no obvious relationswith the interstellar field direction. The near-infrared albedo ofcircumstellar dust is quite high both in the case of LkH-alpha 198 and V376 Cas, which indicates a larger particle size than typical forinterstellar dust.
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The Influence of Stellar Wind on the Motion of the Binary HD698
Not Available
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Close binaries observed polarimetrically
Not Available
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Groups of stars with common motion in the Galaxy - Groups of B stars of luminosity classes I and II and their comparison with groups of long-period Cepheids and open clusters
In a sample of 93 stars of luminosity classes I and II, ten groups withcommon motion in space are isolated. The reality of five groups isestablished by numerical experiment. A comparison is made with groups oflong-period Cepheids and open clusters. Regularities in the distributionof groups of different objects in space are found. The reality of therotation of a star aggregate consisting of three Cepheid groups isestablished.
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The evolution of a single and a binary helium star of 2.5 solar masses up to neon ignition
The behavior with time of the radius, the core mass, and otherparameters of a 2.5 solar mass single helium star during its advancedevolution is calculated, and the evolution is compared with that of a2.5 solar mass helium star in a binary system which during its advancedevolution appears to transfer mass to its companion. It is investigatedwhether or not the cores of 2.5 solar mass helium stars collapse andform neutron stars. The results confirm evolution towards core collapseand confirm the model of the formation of Be/X-ray binaries by evolutionwith mass transfer in intermediate-mass binaries.
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Observations of interstellar diffuse absorption band at 4430 A
Observations of the interstellar diffuse absorption band at 4430 A for800 O and B stars in Neckel's (1967) catalog are being carried out, and482 spectra obtained up to September 1983 have been reduced. It isconfirmed that the strength of the interstellar diffuse absorption bandat 4430 A does not simply relate to the abundance of interstellar grainson the line of sight. The relation between the color excess E(B-V) andthe equivalent width of the band to the direction of l = 130-140 deg andb = -5 to +5 deg shows that some parameter(s) other than E(B-V) is (are)needed to understand the cause of this band.
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Programmes d'observation des binaires spectroscopiques et informations du 14ème catalogue complémentaire
Not Available
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Be-Stars and Shell Stars Observed with the 13-COLOR Photometric System - Part Two
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1984RMxAA...9..141S&db_key=AST
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IUE low-dispersion reference atlas
This atlas, published by ESA and essentially devoted to normal stars,presents 229 graphic spectra together with the corresponding fluxes andan ultraviolet spectral type. The preparation of this publicationconfirmed that MK classifications cannot simply be transferred to theultraviolet range. A set of transparencies illustrates the referencesequences constructed from the ultraviolet data. A magnetic-tape copy ofall the spectra pertaining to this atlas is available from the StellarData Center in Strasbourg.
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Spectroscopic binaries - 14th complementary catalog
Orbital-element data for 380 spectroscopic binaries are compiled andannotated in tables. The catalog represents a continuation of the 13thcatalog (Pedoussaut and Nadal, 1977) and uses the same general format.The techniques used in making the magnitudes and spectral typeshomogeneous are indicated.
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IUE low-dispersion spectra flux catalogue. I - Normal stars (magnetic tape)
A magnetic tape catalog of the fluxes (2A-step) of 229 selectedlow-dispersion stellar spectra prepared by the Centre de Calcul deStrasbourg-Cronenbourg is presented in the form of a set of tables. Thecatalog uses the general MK frame and centers on stars exhibiting normalbehavior in the ultraviolet. All the stars included in the catalog arelisted together with their MK and UV spectral classifications. Thespectra were collected by the International Ultraviolet Explorer (IUE)with the aim of establishing reference spectral sequences in theultraviolet range.
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Variable Stars in the Northern Luminous Stars Catalogues
Not Available
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Thirteen-color photometry of Be stars
Thirteen-color photometry made at the San Pedro Matir Observatory inBaja California for a number of spectroscopically variable Be and shellstars is presented. Several of these stars show photometric variabilityin the UV and/or IR over a time base of two to three years. The moreinteresting stars are analyzed in terms of color-color diagrams, colorexcesses, spectral characteristics and changes in their energydistributions. Prospects for future research are discussed.
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Five-color band ultraviolet photometry of fourteen close binaries
Photometric observations obtained with the Astronomical NetherlandsSatellite in five ultraviolet wavelength regions for 14 close binariesare presented. Strong excess far-ultraviolet flux is detected in fourobjects. The binaries TT Hya, RX Cas, and SX Cas exhibit a pronouncedexcess of far-ultraviolet flux, which is thought to be the result ofmass transfer phenomena in these systems. Observations of the binary RAra show very peculair variations; its far ultraviolet flux at 1550 Abrightened by 0.4 mag between phases 0.7 and 0.8, while its nearultraviolet flux at 3300 A decreased by 0.5 mag over this same half-dayinterval. The A0 II-III component in the system RZ Sct is seen todominate the ultraviolet spectrum.
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A classification of Be stars
Based upon a sample of 140 stars observed over 20 years for which about5,000 spectrograms are available, a classification scheme of Be stars ispresented. This is the first attempt to subdivide the Be star group intophysically significant subgroups, from which typical objects can beselected for further study. The four groups proposed are based upon adiscussion of spectrum characteristics, multicolor photometry,polarization, rotational velocities, UV spectral types and timevariability. Starting with the group membership of a Be star,predictions can be made of the future behavior of it.
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A comparison of the orbital inclinations of the spatially close spectroscopic double stars
The reported investigation takes into account 888 spectroscopicbinaries. It was possible to obtain 120 groups whose elements arespatially close according to the given definition. These 120 groupscontain 313 spectroscopic binaries. 136 of these binaries are 2-spectrumsystems, 177 are 1-spectrum systems, and 62 are eclipsing binaries. Thenumber of systems with known luminosity class is 54. The spectraldistribution of the 313 systems is discussed. The orbital inclinationsand other parameters are presented in a table.
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A spectroscopic reinvestigation of the massive binary HD 698.
Abstract image available at:http://adsabs.harvard.edu/abs/1978PASP...90..179H
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Seventh catalogue of the orbital elements of spectroscopic binary systems.
Not Available
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New position determinations, and other data, for 1280 known Hα-emission stars in the milky way.
Not Available
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INHABITED SKY
