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Spectroscopic and photometric observations of the selected Algol-type binaries - IV. V799Cassiopeiae, BX Piscium and HD 172189 We present new radial velocities and UBV photometric observations ofthree eclipsing binaries, V799Cas, BXPsc and HD172189, in order toincrease the number of close binaries with absolute parametersdetermined accurately. Standard wide-band indices for the systems andcomparison stars were determined accurately. Using the times ofmid-eclipses, new ephemerides are calculated for three systems. V799Casand HD172189 consist of two well-detached components in eccentricorbits. BXPsc is a single-lined eclipsing binary which consists of alate-A and an early-K star. The effective temperatures of the hottercomponents and reddening of the systems have been estimated from Johnsonwide-band UBV photometric calibrations. The UBV photometric data andradial velocities were analysed simultaneously for the systems'parameters using Wilson-Devinney code. The masses have been found to be3.08 +/- 0.40, 2.97 +/- 0.40; 1.85 +/- 0.14, 0.80 +/- 0.08; 2.06 +/-0.15, 1.87 +/- 0.14 Msolar for the primary and secondarystars of V799Cas, BXPsc and HD172189, respectively. The radii of thecomponents are derived in the case of V799Cas: 3.23 +/- 0.14, 3.20 +/-0.14; in those of BXPsc: 3.76 +/- 0.14, 2.18 +/- 0.09; and HD172189:4.01 +/- 0.09, 2.97 +/- 0.07 Rsolar. We have calculated thedistances to the systems of V799Cas, BXPsc and HD172189 as 607 +/- 35,213 +/- 6 and 432 +/- 12 pc, respectively, using bolometric magnitudesand empirical bolometric corrections for the component stars. The modelpredictions match the measured properties of V779Cas, BXPsc and HD172189for an age of 250 Myr, 1 Gyr and 890 Myr, respectively. A subsolarfractional metal abundance, Z ~ 0.008, provides a better match to theabsolute parameters of all three systems.Based on observations collected at the Catania Astrophysical Observatory(Italy), Ege University Observatory (?zmir, Turkey) and DavidDunlap Observatory (Canada).E-mail: cibanoglu@ege.edu.tr
| Ein minimum von LL Aqr (gerade noch) beobachtet. Not Available
| Spectroscopic and photometric observations of the selected Algol-type binaries - III. LL Aquarii, MP Delphini and NSV 20913 We present new radial velocities and photometric observations of threedouble-lined eclipsing binaries LL Aqr, MP Del and NSV 20913. This paperis the third in the planned series of investigations. Standard wide-bandindices for the systems and comparison stars were determined accurately.Using the times of mid-eclipses, new ephemerides are calculated for thethree systems. These systems consist of two well-detached components ineccentric orbits. The effective temperatures of the hotter componentsand reddening of the systems have been estimated from Johnson wide-bandUBV photometric calibrations. New UBV photometric data and radialvelocities were analysed simultaneously for the systems' parametersusing Wilson-Devinney (WD) code. The masses have been found to be 1.223+/- 0.058,1.056 +/- 0.051; 1.559 +/- 0.085,1.248 +/- 0.074; 1.76 +/-0.13 and 1.28 +/- 0.11Msolar for the primary and secondarystars of LL Aqr, MP Del and NSV20913, respectively. The radii of thecomponents are derived in the case of LL Aqr: 1.325 +/- 0.020,1.005 +/-0.016; in those of MP Del: 2.428 +/- 0.046,1.575 +/- 0.030; andNSV20913: 3.243 +/- 0.081,1.291 +/- 0.033Rsolar. The masses,radii and effective temperatures of the component stars have beendetermined with an accuracy of 5-8, 2-3 and 1-3 per cent, respectively.We have calculated the distances to the systems of LL Aqr, MP Del andNSV 20913 as 123 +/- 9,149 +/- 7 and 246 +/- 9 pc, respectively, usingbolometric magnitudes and empirical bolometric corrections for thecomponent stars. The stellar model prediction match the measuredproperties of LL Aqr for an age of about 1.78Gyr, indicating thecomponents near the half of their core-hydrogen-burning lifetimes.However, the components of MP Del have an age of 1.59Gyr, the primarycomponent being turn off from the main sequence. The age of theNSV20913's components is about 1Gyr, indicating the primary componentseems to have evolved just slightly off the main sequence but the lessmassive secondary component is still close to the zero-age mainsequence. A subsolar fractional metal abundance, Z ~ 0.008, provides abetter match to the absolute parameters of all three systems.
| Programmsterne: Beobachtungen erwuenscht. Not Available
| 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
| 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 Elements for 80 Eclipsing Binaries IV. This research presents new elements for 80 eclipsing binaries found withthe help of the ASAS-3, Hipparcos and NSVS databases.
| Neue Anmerkungen zu NN Delphini. Not Available
| Bericht uber NN Del. Not Available
| 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.
| Hipparcos: The Stars Not Available
| The 74th Special Name-list of Variable Stars We present the Name-list introducing GCVS names for 3153 variable starsdiscovered by the Hipparcos mission.
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Takýmyýldýz: | Kova |
Sað Açýklýk: | 22h34m42.15s |
Yükselim: | -03°35'58.2" |
Görünürdeki Parlaklýk: | 9.332 |
özdevim Sað Açýklýk: | 72.9 |
özdevim Yükselim: | -22.9 |
B-T magnitude: | 9.978 |
V-T magnitude: | 9.386 |
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