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HD 213863 (EE Aqr)


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Orbital Solutions and Absolute Elements of the Eclipsing Binary EE Aquarii
EE Aqr is a 7.9 mag Algol variable with a 12 hr orbital period. TheWilson-Devinney program is used to simultaneously solve 11 previouslypublished light curves together with two existing radial velocitycurves. The resulting masses are M 1 = 2.24 ± 0.13 Msun and M 2 = 0.72 ± 0.04 M sun,and the radii are R 1 = 1.76 ± 0.03 R sunand R 2 = 1.10 ± 0.02 R sun. The system hasthe lower-mass component completely filling its Roche lobe. Its distancefrom Hipparcos observations is 112 ± 10 pc. An improved ephemerisis derived, and no deviations in the period over time were seen. Lightand velocity curve parameters, orbital elements, and absolute dimensionsare presented, plus a comparison is made with previous solutions.

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

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.

Automatic classification of eclipsing binaries light curves using neural networks
In this work we present a system for the automatic classification of thelight curves of eclipsing binaries. This system is based on aclassification scheme that aims to separate eclipsing binary systemsaccording to their geometrical configuration in a modified version ofthe traditional classification scheme. The classification is performedby a Bayesian ensemble of neural networks trained with Hipparcos data ofseven different categories including eccentric binary systems and twotypes of pulsating light curve morphologies.

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/.

Minimum Times of Several Eclipsing Binaries
We present 26 minima times of 11 eclipsing binaries, observed between1996 and 1999.

CN Andromedae: A Broken-Contact Binary?
We solve new UBV light curves of the eclipsing binary CN Andromedaesimultaneously with radial velocities by the method of differentialcorrections. We find it semidetached with the more massive star fillingits limiting lobe and the less massive star very close to lobe-filling.Our solutions of earlier light curves have the same configuration.Within the uncertainties, the system may be in a broken or a marginalcontact stage as it undergoes thermal relaxation oscillations. The lightcurves are strongly affected by a large dark spot at high latitude onthe more massive star and by a bright substellar spot on the companion.Spot locations and temperatures do not differ significantly from epochto epoch. Based on single star evolutionary models, the primary's mass(1.299+/-0.045 Msolar) and radius (1.425+/-0.016Rsolar) are consistent with those of a star of age2.9×109 yr that will leave the main sequence in another2.0×109 yr. The orbital period has decreased during thepast 50 yr according to traditional eclipse timings and also accordingto our generalized light and velocity solutions that include a referenceepoch T0 and a rate of period change dP/dt. We finddP/dt=-0.01951+/-0.00054 s yr-1, which is consistent withmass transfer from the more to the less massive star of1.4×10-7 Msolar yr-1, assuming nomass is lost from the system. Reliable absolute dimensions aredetermined.

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.

The calculation of critical rotational periods in three typical close binary systems based on synchronization theory.
Not Available

Measurement and study of rotation in close binary stars (III) Statistical analysis of synchronization.
Not Available

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

Near-Contact Binary Systems in the ROSAT All-Sky Survey
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996ApJ...461..951S&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.

A Study of the Binary GR Tauri from Optical and Infrared Observations
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995AJ....110.1796L&db_key=AST

Measurement and analysis of rotation in close binaries. II. Calculation of synchronism.
Not Available

Radio continuum emission from stars: a catalogue update.
An updated version of my catalogue of radio stars is presented. Somestatistics and availability are discussed.

Near-contact binaries
Not Available

Measurement and Analysis of Rotation in Close Binary Stars - Part One - Observations and Results
Not Available

Ee-Aquarii - a Marginal Contact System
New solutions of the photometric light curves of the close binary EEAquarii, obtained in two different periods, have been performed using aprocedure based on the classical Wilson & Devinney model. Moreover,the first simultaneous solution of photometric and radial-velocitycurves has been obtained. The evolutionary status, which seems to favoura contact configuration not yet in thermal equilibrium, is discussed.

The evolution of low-mass close binary systems with both MS-components.
The evolution of low-mass close binary systems with both MS-componentscaused by the orbital angular momentum loss by magnetic braking isstudied. The evolutionary paths DM?DW?KW and DM?SD of "RCMa-type" ? low-massive KE are discussed.

Program of Parallax Measurements from Space for the Nearest Eclipsing Binaries
Not Available

A Note on the BBSAG Visual Observations
This Letter contains some comments on the communication by Diethelm andLocher (1988) concerning the period variations in the eclipsing binarysystems EE Aqr, BZ Eri, IZ Per, and VZ Hya. Significance of the BBSAGvisual observations has been discussed.

UBVRI photometry of the short-period eclipsing binaries EE Aqr, RV Gru and RW PsA
The authors present photometric observations in the Cousins UBVRIstandard system of the two eclipsing binaries EE Aqr and RV Gru , anddifferential photometry of the system RW PsA. They give new times ofminima and improved linear ephemerides.

Contact and near-contact binary systems. IX - EE Aquarii and RS INDI
Reticon spectroscopy for the short-period binary systems EE Aquarii andRS Indi, and BVRI(c) photometry for RS Indi, are presented for the firsttime. The analyses of these data for masses, radii, and luminositiesshow that both systems are close to semidetached states with thelow-mass secondary components both filling 94 + or - 3 percent of theirRoche lobes. The primary component of RS Ind similarly fills 93 + or - 3percent of its Roche lobe, whilst that of EE Aqr fills 86 + or - 3percent. The albedos of the secondary components are found to be normalfor convective atmospheres, indicating that at the present time there isno energy transfer between the components.

The evolutionary state of contact and near-contact binary stars
A compilation is presented of the masses, radii, and luminosities of thecomponents of 31 F-K type binary systems which have been found to be incontact or near-contact states. Comparisons of these data with thoseexpected for single stars demonstrates that: (1) the primary componentsof the shallow-contact W-type WUMa systems are unevolved main-sequencestars, while those of the deeper-contact A-type systems are near to theterminal-age main sequence; (2) the secondary components of the W-typesystems have radii of the order of 1.5 times larger than expected fortheir ZAMS masses, while those of the A-type systems have radii of theorder of three times larger; (3) the nine systems in the sample which donot display EW-type light curves can be divided into three marginalcontact systems, five semidetached systems, and one detached system. Theimplications of these findings for the types of evolution into contactare addressed.

A microwave survey of southern active stars
The results of a survey of 153 active-chromosphere stars made with theParkes 64-m telescope at 5.0/8.4 GHz from 1981 to 1987 are reported.Microwave emission was detected from 70 stars on at least one occasion,with the highest detection rate of 68 percent from the RS CVn group. TheCa II stars and Algol-type binaries yielded detection rates of 44 and 30percent, respectively. The maximum powers emitted by the stars at5.0/8.4 GHz ranged over five orders of magnitude, with a median of 2.5 x10 to the 10th W/Hz. The maximum brightness temperatures had a smallerrange of three orders of magnitude, with a median of 3.6 x 10 to the 9thK.

New Observed Times of Minima for EE Aqr, RV Gru and RW PsA
Not Available

The List of the Nearest and Bright Eclipsing Binaries from the HIPPARCOS Program
Not Available

Period variations of the eclipsing system EE Aquarii
An O-C diagram of EE Aquarii was compiled using the times of the systemminima observed between 1940 and 1985 for calculation of the the O-Cvalues. In order to differentiate the various observations, the weighedmeans of the O-C values were obtained by giving arbitrary weights 1, 2,and 3 to the visual, the photographic, and the photoelectricobservations, respectively; thus, a diagram based on the weighted O-Cvalues was constructed. An analysis of period variations present in thesystem has disclosed four period decreases, three period increases (withthe strongest period change seen between 1957 and 1959), and elevenperiod fluctuations. The total period change in different portions ofthe O-C diagram based on the weighted O-C values was found to be between1.7 x 10 to the -7 and 8.2 x 10 to the -6 d.

Eclipsing Binaries - Andromeda to Camelopardalis in 1972-1983
Not Available

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Посматрања и Астрометриски подаци

Сазвежђа:Водолија
Ректацензија:22h34m41.97s
Deклинација:-19°51'35.3"
Apparent магнитуда:8.095
Даљина:112.108 parsecs
Proper motion RA:16.5
Proper motion Dec:-9.1
B-T magnitude:8.527
V-T magnitude:8.131

Каталог и designations:
Proper именаEE Aqr
  (Edit)
HD 1989HD 213863
TYCHO-2 2000TYC 6389-1223-1
USNO-A2.0USNO-A2 0675-37032725
HIPHIP 111452

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