B.R.N.O. Contributions #34
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Radial Velocities of RR Lyrae Stars
We report 84 radial velocities for 36 field RR Lyrae variable stars. Thetypical uncertainty of a single velocity is estimated at +/-0.5 kms-1. Our sample consists of variables with insufficientpre-existing data for reliable center-of-mass radial velocitydeterminations. We have computed center-of-mass velocities from our newvelocities using RR Lyr velocity templates. The center-of-mass radialvelocities have a typical uncertainty of +/-1.5 km s-1 forvariables observed at least three times.
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A new catalogue of eclipsing binary stars with eccentric orbits
A new catalogue of eclipsing binary stars with eccentric orbits ispresented. The catalogue lists the physical parameters (includingapsidal motion parameters) of 124 eclipsing binaries with eccentricorbits. In addition, the catalogue also contains a list of 150 candidatesystems, about which not much is known at present.Full version of the catalogue is available online (see the SupplementaryMaterial section at the end of this paper) and in electronic form at theCDS via http://cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/MNRAS/(vol)/ (page)E-mail: ibulut@comu.edu.tr
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A catalogue of close binaries located in the δ Scuti region of the Cepheid instability strip
A catalogue of close eclipsing binary systems (detached andsemidetached) with at least one of the components located in the δScuti region of the Cepheid instability strip is presented. Thepositions of the stars in the instability strip are determined by theiraccurate temperatures and luminosities. Observationally detectedbinaries (20 semidetached, four detached and one unclassified) withoscillating components were included in the catalogue as a separatetable. The primaries of the oscillating Algols tend to be located nearthe blue edge of the instability strip. Using reliable luminosities andtemperatures determined by recent photometric and spectroscopic studies,we have found that at least one or two components of 71 detached and 90semidetached systems are located in the δ Scuti region of theCepheid instability strip. In addition, 36 detached or semidetachedsystems discovered by the Hipparcos satellite were also given as aseparate list. One of their components is seen in the δ Scutiregion, according to their spectral type or B - V colours. They arepotential candidate binaries with the δ Scuti-type pulsatingcomponents which need further photometric and spectroscopic studies inbetter precision. This catalogue covers information and literaturereferences for 25 known and 197 candidate binaries with pulsatingcomponents.
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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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Up-to-Date Linear Elements of Eclipsing Binaries
About 1800 O-C diagrams of eclipsing binaries were analyzed and up-todate linear elements were computed. The regularly updated ephemerides(as a continuation of SAC) are available only in electronic form at theInternet address: http://www.as.ap.krakow.pl/ephem/.
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Photometry of δ Sct-type and Related Stars: Results of AD Ari, IP Vir and YZ Boo
Photometric results of three δ Scuti stars, AD Ari, IP Vir and YZBoo from new observations obtained at the Xinglong Station of theBeijing Astronomical Observatory (BAO) during 2000 and 2001 arereported. We present here the preliminary analyses. Detailed studies ofthese stars based on additional data will be published separately.
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Stability of Pulsation of V577 Ophiuchi
This note presents the light curves for V577 Oph collected at BAO in2000
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delta Scuti and related stars: Analysis of the R00 Catalogue
We present a comprehensive analysis of the properties of the pulsatingdelta Scuti and related variables based mainly on the content of therecently published catalogue by Rodríguez et al.(\cite{retal00a}, hereafter R00). In particular, the primaryobservational properties such as visual amplitude, period and visualmagnitude and the contributions from the Hipparcos, OGLE and MACHOlong-term monitoring projects are examined. The membership of thesevariables in open clusters and multiple systems is also analyzed, withspecial attention given to the delta Scuti pulsators situated ineclipsing binary systems. The location of the delta Scuti variables inthe H-R diagram is discussed on the basis of HIPPARCOS parallaxes anduvbybeta photometry. New borders of the classical instability arepresented. In particular, the properties of the delta Scuti pulsatorswith nonsolar surface abundances (SX Phe, lambda Boo, rho Pup, delta Deland classical Am stars subgroups) are examined. The Hipparcos parallaxesshow that the available photometric uvbybeta absolute magnitudecalibrations by Crawford can be applied correctly to delta Scutivariables rotating faster than v sin i ~ 100 km s{-1} withnormal spectra. It is shown that systematic deviations exist for thephotometrically determined absolute magnitudes, which correlate with vsin i and delta m1. The photometric calibrations are found tofit the lambda Boo stars, but should not be used for the group ofevolved metallic-line A stars. The related gamma Dor variables and thepre-main-sequence delta Scuti variables are also discussed. Finally, thevariables catalogued with periods longer than 0fd 25 are examined on astar-by-star basis in order to assign them to the proper delta Scuti, RRLyrae or gamma Dor class. A search for massive, long-period delta Scutistars similar to the triple-mode variable AC And is also carried out.
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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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A revised catalogue of delta Sct stars
An extensive and up-dated list of delta Sct stars is presented here.More than 500 papers, published during the last few years, have beenrevised and 341 new variables have been added to our last list, sixyears ago. This catalogue is intended to be a comprehensive review onthe observational characteristics of all the delta Sct stars known untilnow, including stars contained in earlier catalogues together with othernew discovered variables, covering information published until January2000. In summary, 636 variables, 1149 references and 182 individualnotes are presented in this new list. Tables 1 and 2 will be accessibleonly in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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Central Asian Network (CAN) - the history and present status
No abstract submitted
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δ Scuti stars: a new revised list
An extensive and up to date list of δ Sct stars is presented. Thiscatalogue is intended to be a comprehensive review of observationalcharacteristics of all the δ Sct stars known until now, includingstars contained in earlier catalogues together with other new discoveredvariables, covering information published until November 1993. Globalinformation in the form of histograms and diagrams are also shown.
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Eclipse Monitoring of Eccentric Binary Systems
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Times of Minimum of Eclipsing Binaries with Non-Circular Orbits
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V577 Ophiuchi: an Eclipsing Binary with a Non-Circular Orbit and a Pulsating Component
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Eclipsing binaries with eccentric orbits
Two groups of eclipsing binaries are dealt with: the first consists ofall binaries with enough data in the General Catalog of Variable Stars(GCVS; Cholopov et al, 1987), the other of those for which accurateparameters are known. In the first group, problems with classificationin GCVS are noticed and several examples of binaries with unexpectedparameters are named. For binaries of the second group, their fractionalradii, ages, and initial radii are used to discuss the relation of theirevolutionary status and orbital eccentricity. Dependence of eccentricityon spectral type and age is observed, and no peak in the initialeccentricity distribution at e = 0 seems to be present. It is suggestedthat binary origin by fragmentation followed by disruption of initialmultiple systems can explain all observed binaries, perhaps with theexception of contact systems in the main sequence. In several cases thecircularization must be due to mass transfer in the eccentric orbit.
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V577 Oph - an Eclipsing Binary with a delta Sct Type Primary Component
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Pulsating Variable Stars in Binary Systems
Lists of variable stars in binary systems are presented.
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An Updated List of Eclipsing Binaries Showing Apsidal Motion
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V577-OPHIUCHI - an Eclipsing System with a High Eccentricity
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Eclipsing binaries in open clusters. I - Preliminary study
A preliminary list of suspected eclipsing binaries in open clusters ispresented. The period, the mass ratio, the correlation between the massratio and cluster age, and the periodicity diagram are investigated.
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Photoelektrische Messungen von 11 langsam und unregelmäßig veränderlichen, nicht roten Sternen.
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162 neue Veräderliche
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