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HD 214791


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Artificial Intelligence Approach to the Determination of Physical Properties of Eclipsing Binaries. I. The EBAI Project
Achieving maximum scientific results from the overwhelming volume ofastronomical data to be acquired over the next few decades demandsnovel, fully automatic methods of data analysis. Here we concentrate oneclipsing binary (EB) stars, a prime source of astrophysicalinformation, of which only some hundreds have been rigorously analyzed,but whose numbers will reach millions in a decade. We describe theartificial neural network (ANN) approach which is able to surmount thehuman bottleneck and permit EB-based scientific yield to keep pace withfuture data rates. The ANN, following training on a sample of 33,235model light curves, outputs a set of approximate model parameters[T2/T1, (R1+R2)/a,esinω, ecosω, and sini] for each input light curve data set.The obtained parameters can then be readily passed to sophisticatedmodeling engines. We also describe a novel method polyfit forpreprocessing observational light curves before inputting their data tothe ANN and present the results and analysis of testing the approach onsynthetic data and on real data including 50 binaries from the Catalogand Atlas of Eclipsing Binaries (CALEB) database and 2580 light curvesfrom OGLE survey data. The success rate, defined by less than a 10%error in the network output parameter values, is approximately 90% forthe OGLE sample and close to 100% for the CALEB sample-sufficient for areliable statistical analysis. The code is made available to the public.Our approach is applicable to EB light curves of all classes; this firstpaper in the eclipsing binaries via artificial intelligence (EBAI)series focuses on detached EBs, which is the class most challenging forthis approach.

Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available

Tertiary companions to close spectroscopic binaries
We have surveyed a sample of 165 solar-type spectroscopic binaries (SB)with periods from 1 to 30 days for higher-order multiplicity. Asubsample of 62 targets were observed with the NACO adaptive opticssystem and 13 new physical tertiary companions were detected. Anadditional 12 new wide companions (5 still tentative) were found usingthe 2MASS all-sky survey. The binaries belong to 161 stellar systems; ofthese 64 are triple, 11 quadruple and 7 quintuple. After correction forincompleteness, the fraction of SBs with additional companions is foundto be 63% ± 5%. We find that this fraction is a strong functionof the SB period P, reaching 96% for P<3d and dropping to34% for P>12^d. Period distributions of SBs with and withouttertiaries are significantly different, but their mass ratiodistributions are identical. The statistical data on the multiplicity ofclose SBs presented in this paper indicates that the periods and massratios of SBs were established very early, but the periods of SB systemswith triples were further shortened by angular momentum exchange withcompanions.

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.

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.

Updated Elements for Southern Eclipsing Binaries
Analysis of ASAS-3 data for 442 southern eclipsing binaries yielded 131stars with incorrect periods listed in the GCVS catalog

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 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

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.

Identification of Variable Stars in Grus
Not Available

Accurate Positions Of Variable Stars Near The South Galactic Pole
Not Available

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.

The active dynamo stars: RS CVn, BY Dra, FK Com, Algol, W UMa, and T Tau
Not Available

The visual surface brightness method and the radii of dwarf Cepheids
In order to determine the radii of dwarf Cepheids by applying the visualsurface brightness method, the empirical relationship between F(v) and(b - y) was derived. Seventeen stars of spectral type A to F, where bothangular diameters and uvby beta photometric data are available, wereselected from the literature. A theoretical F(v), (b-y) relation wasderived by using the Kurucz model atmospheres. It was found that thetheoretical relation is strongly dependent upon metallicity and surfacegravity. To demonstrate that the visual surface brightness method is aneffective way to determine the radii of dwarf Cepheids, both theoreticaland empirical relations were applied to seven dwarf Cepheids. The mostreliable result was obtained for AD CMi where the quality of the radialvelocity data is superior.

UVBY observations of A, F, G and K field stars
Photoelectric data in the uvby system have been obtained for about 800southern stars of the Hipparcos Input Catalog (Grenon, 1982, 1985). Mostof the stars are F and G main sequence and fall in the magnitude range V= 8-11.

UBV Light Variation and Orbital Elements of W-Gruis
In each of the UBV band-passes 2440 observations define for the firsttime the photoelectric light variation of the binary system W Gru. Aconsistent set of elements is derived in the framework of Russell'sclassic and Napier's synthesis models. Absolute dimensions are derived.The system seems to be a well-detached binary consisting of two normal,not interacting, F5 IV components.

Information on the photoelectric observations of variable stars deposited at Odessa Astronomical Observatory
Not Available

Information on the Photoelectric Observations of Variable Stars Deposited at Odessa Astronomical Observatory
Not Available

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.

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 uvby, beta photometric survey of southern hemisphere
A uvby, beta photometric study of southern hemisphere eclipsing binarystars has been undertaken at Cerro Tololo Inter-American Observatory.The standardized colors and V magnitudes for 288 binaries at quadratureand/or at minimum are presented, along with an indication of theaccuracy of the standardization and photometry. Discussions of theresolving time of the pulse-counting photometers and of the atmosphericextinction at CTIO are included.

Improved Light Elements of W Gruis
Not Available

Close binary systems before and after mass transfer. III - Spectroscopic binaries
A method is presented, for the computation of absolute dimensions fromspectroscopic data on binary systems, which has been adapted for usewith the 7th Catalogue of Batten et al. (1978) and takes into accountseveral results of close binary evolution, with emphasis on the phase ofslow mass transfer during a case B mass transfer. Among the unevolvedsystems, the mass transfer case B is found to be the most abundant typeof interaction. In the set of evolving systems, a subset of 18interacting systems was found with mass ratio near unity, the first starbeing the mass loser as well as the brightest.

Light Elements of W Gru
Not Available

A catalogue of parameters for eclipsing binaries
Not Available

Photoelectrically-Neglected Eclipsing Binaries
Not Available

Seventh catalogue of the orbital elements of spectroscopic binary systems.
Not Available

Photographische Beobachtung einiger Veränderlicher im Felde beta Gruis.
Not Available

Binaires spectroscopiques-13e catalogue complementaire.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977A&AS...27...55P&db_key=AST

UVBY BET photometry of equatorial and southern bright stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977A&AS...27...47H&db_key=AST

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קבוצת-כוכבים:עגור
התרוממות ימנית:22h41m18.67s
סירוב:-43°50'28.6"
גודל גלוי:8.964
מרחק:224.215 פארסק
תנועה נכונה:0.5
תנועה נכונה:-31.1
B-T magnitude:9.539
V-T magnitude:9.012

קטלוגים וכינוים:
שם עצם פרטי
HD 1989HD 214791
TYCHO-2 2000TYC 8010-1452-1
USNO-A2.0USNO-A2 0450-40323154
HIPHIP 112009

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