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TYC 4435-1750-1


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Absolute Properties of the Eclipsing Binary Star BF Draconis
BF Dra is now known to be an eccentric double-lined F6+F6 binary starwith relatively deep (0.7 mag) partial eclipses. Previous studies of thesystem are improved with 7494 differential photometric observations fromthe URSA WebScope and 9700 from the NFO WebScope, 106 high-resolutionspectroscopic observations from the Tennessee State University 2 mautomatic spectroscopic telescope and the 1 m coudé-feedspectrometer at Kitt Peak National Observatory, and 31 accurate radialvelocities from the CfA. Very accurate (better than 0.6%) masses andradii are determined from analysis of the two new light curves and fourradial velocity curves. Theoretical models match the absolute propertiesof the stars at an age of about 2.72 Gyr and [Fe/H] = -0.17, and tidaltheory correctly confirms that the orbit should still be eccentric. Ourobservations of BF Dra constrain the convective core overshootingparameter to be larger than about 0.13 Hp . We find, however,that standard tidal theory is unable to match the observed slow rotationrates of the components' surface layers.

Random forest automated supervised classification of Hipparcos periodic variable stars
We present an evaluation of the performance of an automatedclassification of the Hipparcos periodic variable stars into 26 types.The sub-sample with the most reliable variability types available in theliterature is used to train supervised algorithms to characterize thetype dependencies on a number of attributes. The most useful attributesevaluated with the random forest methodology include, in decreasingorder of importance, the period, the amplitude, the V-I colour index,the absolute magnitude, the residual around the folded light-curvemodel, the magnitude distribution skewness and the amplitude of thesecond harmonic of the Fourier series model relative to that of thefundamental frequency. Random forests and a multi-stage scheme involvingBayesian network and Gaussian mixture methods lead to statisticallyequivalent results. In standard 10-fold cross-validation (CV)experiments, the rate of correct classification is between 90 and 100per cent, depending on the variability type. The main mis-classificationcases, up to a rate of about 10 per cent, arise due to confusion betweenSPB and ACV blue variables and between eclipsing binaries, ellipsoidalvariables and other variability types. Our training set and thepredicted types for the other Hipparcos periodic stars are availableonline.

B.R.N.O. Contributions #37 - Times of minima
Paper presents observations of eclipsing binaries acquired by theVariable Star and Exoplanet Section of Czech Astronomical Societymembers (B.R.N.O. observing project) and cooperating observers. Papercontains 1270 minima timings for 478 eclipsing binaries, obtained by 45observers during 2009 - 2011 period. Some neglectedsouthern eclipsing binaries are included in the list. New accurateorbital elements have been found for 28 binary systems. Times of minimaof an extraordinary quadruple sytem V994 Her are presented as well.

BAV-Results of Observations - Photoelectric Minima of Selected Eclipsing Binaries and Maxima of Pulsating Stars
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BAV-Results of Observations - Photoelectric Minima of Selected Eclipsing Binaries and Maxima of Pulsating Stars
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Relativistic apsidal motion in eccentric eclipsing binaries
Context. The study of apsidal motion in detached eclipsing binarysystems is known to be an important source of information about stellarinternal structure as well as the possibility of verifying of GeneralRelativity outside the Solar System. Aims: As part of thelong-term Ond?ejov and Ostrava observational projects, we aim tomeasure precise times of minima for eccentric eclipsing binaries, neededfor the accurate determination of apsidal motion, providing a suitabletest of the effects of General Relativity. Methods: About seventynew times of minimum light recorded with photoelectric or CCDphotometers were obtained for ten eccentric-orbit eclipsing binarieswith significant relativistic apsidal motion. Their O-C diagrams wereanalysed using all reliable timings found in the literature, and new orimproved elements of apsidal motion were obtained. Results: Weconfirm very long periods of apsidal motion for all systems. For BF Draand V1094 Tau, we present the first apsidal-motion solution. Therelativistic effects are dominant, representing up to 100% of the totalobservable apsidal-motion rate in several systems. The theoretical andobserved values of the internal structure constant k 2 werecompared for systems with lower relativistic contribution. Using thelight-time effect solution, we predict a faint third component for V1094Tau orbiting with a short period of about 8 years.Partly based on photoelectric observations secured at the HvarObservatory, Faculty of Geodesy, Zagreb, Croatia, in October 2008.

B.R.N.O. Contributions #34
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New Times of Minima of Some Eclipsing Variables
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Precise Times of Minimum Light of Neglected Eclipsing Binaries
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Pulkovo compilation of radial velocities for 35495 stars in a common system.
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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.

New Times of Minima of Some Eclipsing Variables
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Times of Minimum Light of Neglected Eclipsing Binaries
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SB9: The ninth catalogue of spectroscopic binary orbits
The Ninth Catalogue of Spectroscopic Binary Orbits(http://sb9.astro.ulb.ac.be) continues the series of compilations ofspectroscopic orbits carried out over the past 35 years by Batten andcollaborators. As of 2004 May 1st, the new Catalogue holds orbits for2386 systems. Some essential differences between this catalogue and itspredecessors are outlined and three straightforward applications arepresented: (1) completeness assessment: period distribution of SB1s andSB2s; (2) shortest periods across the H-R diagram; (3)period-eccentricity relation.

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/.

Catalogue of Algol type binary stars
A catalogue of (411) Algol-type (semi-detached) binary stars ispresented in the form of five separate tables of information. Thecatalogue has developed from an earlier version by including more recentinformation and an improved layout. A sixth table lists (1872) candidateAlgols, about which fewer details are known at present. Some issuesrelating to the classification and interpretation of Algol-like binariesare also discussed.Catalogue is only available in electronic form at the CDS via anonymousftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/417/263

uvbyβ Photometry of Selected Eclipsing Binary Stars
New uvbyβ observations of 51 eclipsing binary stars are presented,and outside-eclipse averages for 45 of them are given. Many of thesebinaries are detached main-sequence pairs that have been discovered tobe double-lined spectroscopic binaries and appear suitable fordeterminations of accurate absolute dimensions and masses. Photometricproperties are recomputed for 14 of the binaries, for which absoluteproperties have been published previously. Intercomparisons are madewith previous photometry, when available, and notes are given for someindividual systems.

149 Bedeckungssterne der BAV-Programme. Eine Analyse der Beobachtungstatigkeit seit den Angangen.
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Das Brunner Punktesystem.
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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.

Photoelectric Minima of Selected Eclipsing Binaries and Maxima of Pulsating Stars
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A Spectroscopic Survey of Late F--K Eclipsing Binaries
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996ApJS..106..133P&db_key=AST

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.

Eclipse Monitoring of Eccentric Binary Systems
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BF Draconis
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UBV photometry of selected eclipsing binary stars
The study reports new UBV observations of 69 eclipsing binary stars andprovides outside-eclipse averages. Revised photometric properties offive of the binaries, for which absolute properties were publishedpreviously, are computed. Comparisons are made with previous photometry,when available, and notes are given for some individual systems.

Spectroscopic binaries - 15th complementary catalog
Published observational data on the orbital characteristics of 436spectroscopic binaries, covering the period 1982-1986, are compiled intables. The data sources and the organization of the catalog are brieflydiscussed, and notes are provided for each item.

Photoelectric radial velocities of eclipsing binaries. I - Orbital elements of BF DRA
Photoelectric spectroscopic observations of the eclipsing binary BF Dra,obtained using the Coravel radial-velocity spectrometer on the 1-m Swisstelescope of the Observatoire de Haute-Provence during 1977-1982, arepresented in tables and graphs and used to determine the orbitalelements. Elements derived include P = 11.2109 d, Kl = 71.7 + or - 0.4km/s, K2 = 73.3 + or - 0.5 km/s, V0 = -30 + or - 0.2 km/s, e = 0.386 +or - 0.003, omega(1) = 271.4 + or - 0.8 deg, T(0) = 2,443,767.36 + or -0.02 JD, m(1) sin3 i = 1.41 + or - 0.03 solar mass, and m(2) sin3 i =1.38 + or - 0.03 solar mass.

Statistics of categorized eclipsing binary systems Lightcurve shapes, periods, and spectral types
The statistics of the light curve morphologies, eclipse depths, orbitalperiods, and spectral types of about 1000 eclipsing binary systems areexamined, after attempting to subdivide these binaries into variousbasic evolutionary categories. The applicability of statisticalcriteria, based on light curve morphologies and eclipse depths, for thecategorization of eclipsing binaries has been found more limited thanpreviously believed. In particular, EW-type light curves turn out to begood indicators of contact systems (though not conversely), while EA-and EB-type light curves have little physical significance. Moreover,the study reveals a strong deficit of short-period noncontact systems inthe whole spectral range, together with an underabundance of early-typecontact binaries (compared with the number of late-type contact pairs).Interestingly, the distribution of evolved Algol-type systems isshifted, on average, to periods longer than those of unevolved detachedsystems in the OB and early A spectral range (and to shorter periods inthe F spectral range).

A catalogue of parameters for eclipsing binaries
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Datos observacionales y astrométricos

Constelación:Dragón
Ascensión Recta:18h50m59.35s
Declinación:+69°52'57.5"
Magnitud Aparente:9.77
Movimiento Propio en Ascensión Recta:6.8
Movimiento Propio en Declinación:26.5
B-T magnitude:10.454
V-T magnitude:9.827

Catálogos y designaciones:
Nombres Propios   (Edit)
TYCHO-2 2000TYC 4435-1750-1
USNO-A2.0USNO-A2 1575-04049998
HIPHIP 92489

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