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Radial Velocity Studies of Close Binary Stars. XV Radial velocity (RV) measurements and sine curve fits to the orbital RVvariations are presented for the last eight close binary systemsanalyzed in the same way as in the previous papers of this series: QXAnd, DY Cet, MR Del, HI Dra, DD Mon, V868 Mon, ER Ori, and Y Sex. Foranother seven systems (TT Cet, AA Cet, CW Lyn, V563 Lyr, CW Sge, LV Vir,and MW Vir), phase coverage is insufficient to provide reliable orbitsbut RVs of individual components were measured. Observations of a fewcomplicated systems observed throughout the David Dunlap Observatory(DDO) close binary program are also presented; among them is anespecially interesting multiple system V857 Her which—in additionto the contact binary—very probably contains one or more subdwarfcomponents of much earlier spectral type. All suspected binaries whichwere found to be most probably pulsating stars are briefly discussed interms of mean RVs and projected rotation velocities (vsin i) as well asspectral-type estimates. In two of them, CU CVn and V752 Mon, thebroadening functions show a clear presence of nonradial pulsations. Thepreviously missing spectral types for Paper I are given here in additionto such estimates for most of the program stars of this paper.Based on the data obtained at the David Dunlap Observatory, Universityof Toronto, Toronto, Canada.
| Recent Minima of 184 Eclipsing Binary Stars This paper continues the publication of times of minima for eclipsingbinary stars from observations reported to the AAVSO Eclipsing BinaryCommittee. Times of minima from observations made from March 2008through August 2008 are presented.
| Recent Minima of 155 Eclipsing Binary Stars The AAVSO's publication of times of minima for eclipsing binary stars has shifted from the recent publication series, Observed Minima Timings of Eclipsing Binaries, Number 1-12, back to the JAAVSO. Times of minima fromobservations made in the past eight months are presented. New lightelements for AC CMi have been calculated from recent AAVSO observations:Min(JD) = 2451978.7504 + 0.867216691 E± 0.0004 ± 0.00000024
| Contact Binaries with Additional Components. III. A Search Using Adaptive Optics We present results of the Canada-France-Hawaii Telescope adaptive optics(AO) search for companions of a homogeneous group of contact binarystars, as a contribution to our attempts to prove the hypothesis thatthese binaries require a third star to become as close as observed. Inaddition to directly discovering companions at separations of>=1″, we introduced a new method of AO image analysis utilizingdistortions of the AO diffraction ring pattern at separations of0.07″-1″. Very close companions, with separations in thelatter range, were discovered in the systems HV Aqr, OO Aql, CK Boo, XYLeo, BE Scl, and RZ Tau. More distant companions were detected in V402Aur, AO Cam, and V2082 Cyg. Our results provide a contribution to themounting evidence that the presence of close companions is a very commonphenomenon for very close binaries with orbital periods <1 day.Based on observations obtained at the Canada-France-Hawaii Telescope,which is operated by the National Research Council of Canada, theInstitut National des Sciences de l'Univers of the Centre National de laRecherche Scientifique of France, and the University of Hawaii.
| Radial Velocity Studies of Southern Close Binary Stars. II. Spring/Summer Systems Radial velocity measurements and sine-curve fits to the orbital velocityvariations are presented for 14 close binary stars, S Ant, TT Cet, TWCet, AA Cet, RW Dor, UX Eri, YY Eri, BV Eri, CT Eri, SZ Hor, AD Phe, TYPup, HI Pup, and TZ Pyx. All are double-lined binaries, and all exceptthe last one are contact binaries. The orbital data must be consideredpreliminary because of the relatively small number of observations(6-12), a circumstance that is partly compensated by the good definitionof the broadening functions used for the radial velocity determinations.Based on data obtained at the European Southern Observatory.
| New Times of Minima of Some Eclipsing Binary Stars 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.
| 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/.
| 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 Not Available
| Photoelectric Minima of Selected Eclipsing Binaries and Maxima of Pulsating Stars Not Available
| Near-contact binaries Not Available
| 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.
| A catalogue of parameters for eclipsing binaries Not Available
| Photoelectric Minima of Eclipsing Binaries Not Available
| Benennung von veränderlichen Sternen Not Available
| 115 neue Veränderliche Not Available
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Besorolás csoportokba:
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Pozíciós és asztrometriai adatok
Csillagkép: | Cet |
Rektaszcenzió: | 01h46m56.50s |
Deklináció: | -09°45'09.8" |
Vizuális fényesség: | 10.916 |
RA sajátmozgás: | 2.2 |
Dec sajátmozgás: | -5.6 |
B-T magnitude: | 11.434 |
V-T magnitude: | 10.959 |
Katalógusok és elnevezések:
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