Proper-motion binaries in the Hipparcos catalogue. Comparison with radial velocity data
Context: .This paper is the last in a series devoted to the analysis ofthe binary content of the Hipparcos Catalogue. Aims: .Thecomparison of the proper motions constructed from positions spanning ashort (Hipparcos) or long time (Tycho-2) makes it possible to uncoverbinaries with periods of the order of or somewhat larger than the shorttime span (in this case, the 3 yr duration of the Hipparcos mission),since the unrecognised orbital motion will then add to the propermotion. Methods: .A list of candidate proper motion binaries isconstructed from a carefully designed χ2 test evaluatingthe statistical significance of the difference between the Tycho-2 andHipparcos proper motions for 103 134 stars in common between the twocatalogues (excluding components of visual systems). Since similar listsof proper-motion binaries have already been constructed, the presentpaper focuses on the evaluation of the detection efficiency ofproper-motion binaries, using different kinds of control data (mostlyradial velocities). The detection rate for entries from the NinthCatalogue of Spectroscopic Binary Orbits (S_B^9) is evaluated, as wellas for stars like barium stars, which are known to be all binaries, andfinally for spectroscopic binaries identified from radial velocity datain the Geneva-Copenhagen survey of F and G dwarfs in the solarneighbourhood. Results: .Proper motion binaries are efficientlydetected for systems with parallaxes in excess of ~20 mas, and periodsin the range 1000-30 000 d. The shortest periods in this range(1000-2000 d, i.e., once to twice the duration of the Hipparcos mission)may appear only as DMSA/G binaries (accelerated proper motion in theHipparcos Double and Multiple System Annex). Proper motion binariesdetected among S_B9 systems having periods shorter than about400 d hint at triple systems, the proper-motion binary involving acomponent with a longer orbital period. A list of 19 candidate triplesystems is provided. Binaries suspected of having low-mass(brown-dwarf-like) companions are listed as well. Among the 37 bariumstars with parallaxes larger than 5 mas, only 7 exhibit no evidence forduplicity whatsoever (be it spectroscopic or astrometric). Finally, thefraction of proper-motion binaries shows no significant variation amongthe various (regular) spectral classes, when due account is taken forthe detection biases.Full Table [see full textsee full text] is only available in electronicform at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5)or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/464/377
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Evolution of interacting binaries with a B type primary at birth
We revisited the analytical expression for the mass ratio distributionfor non-evolved binaries with a B type primary. Selection effectsgoverning the observations were taken into account in order to comparetheory with observations. Theory was optimized so as to fit best withthe observed q-distribution of SB1s and SB2s. The accuracy of thistheoretical mass ratio distribution function is severely hindered by theuncertainties on the observations. We present a library of evolutionarycomputations for binaries with a B type primary at birth. Some liberalcomputations including loss of mass and angular momentum during binaryevolution are added to an extensive grid of conservative calculations.Our computations are compared statistically to the observeddistributions of orbital periods and mass ratios of Algols. ConservativeRoche Lobe Over Flow (RLOF) reproduces the observed distribution oforbital periods but fails to explain the observed mass ratios in therange q in [0.4-1]. In order to obtain a better fit the binaries have tolose a significant amount of matter, without losing much angularmomentum.
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A catalogue of eclipsing variables
A new catalogue of 6330 eclipsing variable stars is presented. Thecatalogue was developed from the General Catalogue of Variable Stars(GCVS) and its textual remarks by including recently publishedinformation about classification of 843 systems and making correspondingcorrections of GCVS data. The catalogue1 represents thelargest list of eclipsing binaries classified from observations.
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Statistical Constraints for Astrometric Binaries with Nonlinear Motion
Useful constraints on the orbits and mass ratios of astrometric binariesin the Hipparcos catalog are derived from the measured proper motiondifferences of Hipparcos and Tycho-2 (Δμ), accelerations ofproper motions (μ˙), and second derivatives of proper motions(μ̈). It is shown how, in some cases, statistical bounds can beestimated for the masses of the secondary components. Two catalogs ofastrometric binaries are generated, one of binaries with significantproper motion differences and the other of binaries with significantaccelerations of their proper motions. Mathematical relations betweenthe astrometric observables Δμ, μ˙, and μ̈ andthe orbital elements are derived in the appendices. We find a remarkabledifference between the distribution of spectral types of stars withlarge accelerations but small proper motion differences and that ofstars with large proper motion differences but insignificantaccelerations. The spectral type distribution for the former sample ofbinaries is the same as the general distribution of all stars in theHipparcos catalog, whereas the latter sample is clearly dominated bysolar-type stars, with an obvious dearth of blue stars. We point outthat the latter set includes mostly binaries with long periods (longerthan about 6 yr).
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CCD Minima for Selected Eclipsing Binaries in 2004
Not Available
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CCD Times of Minima of Selected Eclipsing Binaries
682 CCD minima observations of 259 eclipsing binaries made mainly byauthor are presented. The observed stars were chosen mainly fromcatalogue BRKA of observing programme of BRNO-Variable Star Section ofCAS.
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Times of Minima for Neglected Eclipsing Binaries in 2003
Times of minima for a number of neglected eclipsing binaries arepresented.
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CCD Times of Minima of Some Eclipsing Binaries in 2003
We present CCD observations of minima of 31 eclipsing binaries observedby SAVS sky survey in 2003.
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CCD Minima for Selected Eclipsing Binaries in 2002
Not Available
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The Wolfgang and Amadeus Automatic Photoelectric Telescopes. A ``Kleine-Nacht-Musik'' during the first five years of routine operation
We present a summary of five years of continuous operation of theUniversity of Vienna twin Automatic Photoelectric Telescopes (APTs) --Wolfgang and Amadeus. These two telescopes are part of the FairbornObservatory facility located in the Sonoran desert close to WashingtonCamp in southern Arizona. The detection and distinction procedurebetween weather-induced data-quality loss and systematic data-qualityloss turned out to be a crucial task. Therefore, special emphasis islaid on the data quality monitoring tools developed throughout theyears. Furthermore, we summarize the scientific highlights from thefirst five years of operation
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Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
The Catalogue, available at the Centre de Données Stellaires deStrasbourg, consists of 13 573 records concerning the results obtainedfrom different methods for 7778 stars, reported in the literature. Thefollowing data are listed for each star: identifications, apparentmagnitude, spectral type, apparent diameter in arcsec, absolute radiusin solar units, method of determination, reference, remarks. Commentsand statistics obtained from CADARS are given. The Catalogue isavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcar?J/A+A/367/521
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Stars with the Largest Hipparcos Photometric Amplitudes
A list of the 2027 stars that have the largest photometric amplitudes inHipparcos Photometry shows that most variable stars are all Miras. Thepercentage of variable types change as a function of amplitude. Thiscompilation should also be of value to photometrists looking forrelatively unstudied, but large amplitude stars.
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The BF Aurigae system. A close binary at the onset of mass transfer
Because the question of the mass ratio of the early-type system BF Aurhas not yet fully been clarified, we present and analyse new UBVphotometry and nearly contemporaneous radial velocity observations. Froma simultaneous least squares analysis of the photometric light curvesand the new radial velocity curves we derive a mass ratio of q=1.048+/-0.02. With even much more accurate photometric and spectroscopic datathe mass ratio remains weakly defined. The resulting stellar parametersare consistent with line ratios derived from old and our new spectra andavailable Strömgren indices. We confirm earlier conclusions that BFAur is detached and that the more massive component is almost fillingits Roche lobe. New data indicating a period change support theinterpretation that mass exchange has already started or is about tostart. Tables A1-A5 are available electronically only at the CDS viaanonymous ftp (130.79.128.5) ftp://cdsarc.u-strasbg.fr orhttp://cdsweb.u-strasbg.fr/index.htm
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Variations of the orbital periods in semi-detached binary stars with radiative outer layers
A detailed analysis of the period changes of sixteen semi-detachedbinaries which contain only stars with radiative outer layers(ET-systems) has been performed and their respective O-C diagrams arebrought and discussed. It was found that the course of the periodvariations is monotonic and in some systems the period is even constant.This detailed analysis of extensive sets of timings covering severaldecades brings a strong support to an earlier finding of te[Hall(1989)]{hal89} and develops it further. We show that all systems withthe orbital periods shorter than nine days display constant period orits increase, with the exception of an uncertain case of V 337 Aql. Thecourse of the period variations in TT Aur appears more complex but thecyclic term can be plausibly explained by the third body. A search forgeneral relations between the parameters of the systems and the periodchanges was undertaken. The mass ratio q appears to play a role in theperiod variations. Clear changes in systems with orbital periods shorterthan 9 days were detected only for q>0.4 while constant periods arecommon in systems with q<0.4 in this period range. The sense of thesecular changes in most systems is in accordance with the dominantconservative mass transfer in evolved binary and corresponds to the slowphase. The role of the evolutionary scenarios (case A versus B) and theinfluence of changes of the rotational angular momenta of the componentsare discussed.
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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 Model of the Early Type Binary System BF Aurigae
A physically consistent model is presented for the early-type eclipsingbinary system BF Aur, based on a simultaneous solution of its light andradial velocity curves. The less massive fainter (but hotter) secondaryis smaller but almost Roche lobe filling component. The system is thusnot reverse-algol. The absolute parameters of the system are found tobe: Mh=3.3 Modot, Mc= 4.1Modot, Th= 15600 K, Tc= 15400 K,Rh= 3.9 Rodot, Rc= 4.1Rodot. More accurate radial velocity data are needed beforeuniqueness can be claimed for the model.
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An Analysis of the Light Curves of the Early-Type Binary BF Aurigae
The UBV observations of the massive binary BF Aur were made at theAnkara University Observatory during 1988, 1989 and 1996. Asymmetry ofthe light curves, arising from unequal height of successive maxima,indicates that the system is active. By analysing these observations inthe framework of the Roche model (including the presence of brightregions on the components) one obtains a semidetached configuration ofthe system, with the cooler secondary component filling its Roche lobe.The analysis of the light curves yields consistent solutions for massratio q = m2/m1 somewhat less than one. Theinfluence of the mass transfer on the change of thesystem-orbital-period is relatively small. The upward paraboliccharacter of the O-C diagram (Zhang et al., 1993) indicates a masstransfer from the less massive secondary to the more massive primary.This inturn requires the less massive secondary to fill its Roche lobe.This is consistent with our solution. Based on these facts we introducedthe following working hypothesis. At the place where the gas stream fromthe secondary falls on the primary, relatively small in size but a hightemperature contrast active hot-spot (hs) region is formed. As a resultof the heating effect caused by the irradiation of the hot-spot region,on the secondary's side facing the hot spot a bright-spot (bs) region isformed. The bright-spot region is larger in size but with significantlylower temperature than the hot spot. This region can be treated as a`reflection cap'. By analysing the light curves in the framework of thisworking hypothesis the basic parameters of the system and the activeregions are estimated. The problem is solved in two stages: by obtaininga synthetic light curve in the case when the parameters of thecorresponding Close Binary (CB) Roche model (Djurašević,1992a) are given a priori (the direct problem) and by determining theparameters of the given model for which the best fit between thesynthetic light curve and the observations is achieved (the inverseproblem) (Djurašević, 1992b).
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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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Photoelectric Minima of Eclipsing Binaries
Not Available
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Times of Minima for Some Eclipsing Binaries
Not Available
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New Photoelectric Observations of BF Aurigae
Not Available
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Another look at the early-type eclipsing binary BF Aurigae
Since the question of the mass ratio of the early-type system BF Aur hasnot yet fully been clarified, we reanalyze existing B and V light curvedata from the literature with special consideration to the photometricmass ratio, which we determine as q = 1.05 +/- 0.05. The basicindeterminacy in q(phot) resulting from the light curve shape, i.e., theimpossibility to decide from photometry alone which star is in front atprimary minimum, is overcome by considering the spectral line ratios.The finally adopted stellar parameters are consistent with availableStromgren indices for BF Aur. We confirm earlier conclusions that themore massive component is almost filling its Roche lobe. At present,there are no indications of mass transfer or period changes. The lightcurves, however, show some wavelength-dependent extra light anddisturbances around phase 0.25 that might be related to stellar winds.
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The gravity-darkening of highly distorted stars in close binary systems. VIII - Practical analysis of primary components filling the critical Roche lobe in semi-detached systems of reverse Algol-type
The effective gravity-darkening is studied for the primary componentsfilling the critical Roche lobe in eight semi-detached systems ofreverse Algol-type. From the analysis of light variations outsideeclipses, values of the exponent of gravity-darkening for thesecomponents have been deduced with the assumed values for the secondarycomponents. The derived values of the exponent are found to be greaterthan the unity, confirming the previous result that the empirical valueof the exponent of gravity-darkening for a component star filling thecritical lobe is generally greater than the unity. It is also found thatthe values derived here for the primary components of the reverse Algolsare distinctly smaller than those derived for the secondary componentsin semi-detached systems of normal Algol-type. Based on the mass-outflowdarkening model, the present result would thus indicate that the ratesof mass transfer in reverse Algols are not so high, and might imply thatthe systems are not in the rapid phase of mass transfer
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Statistical study of semi-detached and near-contact semi-detached binaries
A statistical study was made of 107 semidetached with combined lightcurve solutions. An empirical period-dependent mass-radius relation wasderived, thereby revealing the impossibility of having evolvedsemidetached systems with very short periods. Statistically, thenear-contact semidetached systems have the common properties of nearlyequal mass densities of the components, larger mass-ratios, shorterperiods and smaller specific angular momenta, and their A- F-typesecondaries generally have greater densities than the secondaries ofclassical Algol systems of the same spectral types. A detaileddiscussion is also made in this paper on the evolution of near-contactsemidetached binaries.
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Statistical Study on the Semidetached and Near Contact Semidetached Binary Systems
Not Available
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Case a evolution of massive close binary systems. II - Evolution of the systems belonging to the evolution type 1C(Nc)2COf
The evolutionary characteristics of the systems belonging to twoevolution types, designated as 1C2COf and 1Nc2COf, among seven evolutiontypes which were studied in the preceding paper of this series, arepresented. These two types are most complicated and interesting in theevolutionary behavior, which consists of repeated detached,semidetached, and contact phases. Observational aspects of the resultsare discussed.Evolutionary behavior of the systems is also discussed,compared with the thermal relaxation oscillation model.
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Eclipsing Binaries - Andromeda to Camelopardalis in 1972-1983
Not Available
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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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The period distribution of unevolved close binary systems
Period distributions have been examined for various spectral types ofabout 600 (eclipsing and spectroscopic) close binaries, which are likelyto be substantially unevolved. The comparison with the previouscorresponding analyses of extensive (but heterogeneous) binary samplesallows a clarification of the extent of the evolutionary andobservational selection effects. Remarkably, this analysis reveals agreat deficiency of short period binaries (with periods corresponding tocase A mass transfer) in the whole spectral range. For the late spectraltypes, this result may be connected with postformation angular momentumloss caused by stellar wind magnetic braking; at least for the late Band A spectral range, a ready interpretation of this finding is thatclose binaries of corresponding periods and spectral types are rarelyformed.
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VY Lac - A possible semidetached system of early type
483 V and 476 B photoelectric observations of VY Lac have been obtainedand analyzed with the Wilson and Devinney method. The photometricsolution suggests that VY Lac is one of few semidetached systems in theslow stage of case A mass exchange.
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INHABITED SKY
