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Apsidal motion in eccentric eclipsing binaries: CW Cephei, V478 Cygni, AG Persei, and IQ Persei
Aims.About thirty new times of minimum light recorded with photoelectricor CCD photometers were obtained for four early-type eccentric-orbiteclipsing binaries CW Cep (P=2.73d, e=0.029), V478 Cyg ( 2.88d, 0.016),AG Per ( 2.03d, 0.071), and IQ Per ( 1.74d, 0.076). Methods:.Their O-C diagrams were analysed using all reliable timings found inthe literature, and elements of apsidal motion were improved.Results: .We confirm relatively short periods of apsidal motion of about46, 27, 76, and 124 years for CW Cep, V478 Cyg, AG Per, and IQ Per,respectively. The corresponding internal structure constants, log k_2,are then found to be -2.12, -2.25, -2.15, and -2.36, under theassumption that the component stars rotate pseudosynchronously. Therelativistic effects are negligible, being up to 8% of the total apsidalmotion rate in all systems. Using the light-time effect solution, wehave predicted a faint third component orbiting with a period of about39 years for CW Cep.
| Photometry and Analysis of the Eclipsing Binary IQ Persei
Photoelectric observations of the eclipsing binary IQ Persei have beencarried out in B and V colours at Ege University Observatory. Thecorresponding light curves were analyzed by synthesis techniques. Theabsolute physical parameters and apsidal motion period (122 yr) of thesystem were obtained. The results have been compared with theoreticalevolutionary models which include both mass loss and convectiveovershooting. Theoretical evolutionary tracks of the component starsindicate an age of 1.3 × 108 years and an apsidalmotion constant of 0.0040 which is greater than its observed value byonly about 5%. The A7 secondary of the eclipsing pair is still close tothe zero-age main sequence but B7 primary is about halfway through itsmain sequence life-time.
| Absolute dimensions and masses of eclipsing binaries. V - IQ Persei
New photometric and spectroscopic observations of the 1.7 day eclipsingbinary IQ Persei (B8 + A6) have been analyzed to yield very accuratefundamental properties of the system. Reticon spectroscopic observationsobtained at McDonald Observatory were used to determine accurate radialvelocities of both stars in this slightly eccentric large light-ratiobinary. A new set of VR light curves obtained at McDonald Observatorywere analyzed by synthesis techniques, and previously published UBVlight curves were reanalyzed to yield accurate photometric orbits.Orbital parameters derived from both sets of photometric observationsare in excellent agreement. The absolute dimensions, masses,luminosities, and apsidal motion period (140 yr) derived from theseobservations agree well with the predictions of theoretical stellarevolution models. The A6 secondary is still very close to the zero-agemain sequence. The B8 primary is about one-third of the way through itsmain-sequence evolution.
| A UBV photometric study of IQ Persei
Abstract image available at:http://adsabs.harvard.edu/abs/1970PASP...82.1077H
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Membre dels grups següents:
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Dades d'Observació i Astrometria
| Constel·lació: | Perseus |
| Ascensió Recta: | 03h59m44.94s |
| Declinació: | +48°08'25.5" |
| Magnitud Aparent: | 9.213 |
| Moviment propi RA: | 16.2 |
| Moviment propi Dec: | -14.2 |
| B-T magnitude: | 9.319 |
| V-T magnitude: | 9.222 |
Catàlegs i designacions:
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