• 한국우주과학회:학술대회논문집(한국우주과학회보)
• /
• 한국우주과학회 2000년도 한국우주과학회보 제9권1호
• /
• pp.55-55
• /
• 2000

No Abstract, See Full Text

• 한국우주과학회:학술대회논문집(한국우주과학회보)
• /
• 한국우주과학회 1998년도 한국우주과학회보 제7권1호
• /
• pp.15.2-15
• /
• 1998

No Abstract.See Full-text

• 천문학회지
• /
• 제8권1호
• /
• pp.15-23
• /
• 1975

A new technique of photographic observations is developed for the determination of time of minimum light of eclipsing binary. An instrumental system to accomplish the observation is described. With this instrument the atmospheric extinction coefficients in Seoul are observed, and four times of minimum light for Algol and W UMa are determined.

• Journal of Astronomy and Space Sciences
• /
• 제9권1호
• /
• pp.97-110
• /
• 1992

Observed spectra of the long period eclipsing binary VV Cephei show emission features of Balmer and some ionized metal lines. These features were interpreted as the result of the extended envelope activity surrounding the secondary star. Radial velocities and equivalent widths were calculated from some metal lines.

• 천문학회보
• /
• 제30권1호
• /
• pp.74.1-74.1
• /
• 2005

• Journal of Astronomy and Space Sciences
• /
• 제8권2호
• /
• pp.125-131
• /
• 1991

UBV observations at Yonsei University Observatory (500 and 537 observations each at Ilsan Station and at Campus Station) were made for the latest eclipse of $\zeta$ Aur in 1987-1988. Orbital period of Saijo and Saito has been confirmed and the light and color variations on the night JD 244730 are found.

• 천문학회지
• /
• 제2권1호
• /
• pp.10-22
• /
• 1969

Two-Color photoelectric observations were made at Flower and Cook Observatory, University of Pennsylvania. Since the spectroscopic elements are available for the system, derivation of an absolute physical dimension is now expected to be feasible. Results of computation of the orbital elements lead to a fact that the system shows an annular eclipse rather than a partial which is a finding reported by Shapley.

• 천문학회보
• /
• 제25권1호
• /
• pp.42-42
• /
• 2000

• Journal of Astronomy and Space Sciences
• /
• 제27권4호
• /
• pp.263-278
• /
• 2010

Many filtered CCD measures form the basis of six new light curves of the eclipsing system SW Lyn. From these measures and additional observations for eclipse timing, 47 new times of minimum light over the time-interval of about 13 years have been calculated. The complex period variability can be sorted into a linear period improvement with 5.8-year and 33.9-year periodic terms. The shorter cyclic term of these is ascribed to a cool companion of the eclipsing pair but the longer one has no testable interpretation at present. The new light curves are synthesized by the 2003 version of the Wilson-Devinney differential corrections computer code. The results incorporate a source of "third light" which comes from the cool companion star that had been identified by the cycling of the period of the eclipsing pair and also had previously been identified spectroscopically. There is a measure of satisfaction with current understanding of the SW Lyn eclipsing system because of consistent syntheses of all historical light curves. This agreeable convergence, however, comes partly at the expense of an unanticipated temperature of the hot star and of a photospheric spot that has no obvious basis in the detached character modeled for the binary. We offer predictions of changes in the stellar parameters if the modeled detached-configuration should be wrong. The SW Lyn stellar system is still difficult to understand.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
• /
• 한국우주과학회 2003년도 한국우주과학회보 제12권2호
• /
• pp.75-75
• /
• 2003

All published and newly observed times of minimum light of the massive, early-type eclipsing binary star AH Cep were analyzed. After subtracting the light time effect due to the well-known third body from the residuals of the observed times of minimum light, it was found that the second-order Ο-C residuals varied in a cyclical way. It was assumed that the secondary oscillations were produced by a light time effect due to a fourth body so all the times of minimum light were reanalyzed with a differential least-squares scheme in order to obtain the light time orbits due to both the third and fourth bodies. The periods, eccentricities, semi-amplitudes of the light time orbits for the third and fourth-bodies were derived as : P$\_$3/=68.$\^$y/3 and P$\_$4/=9.$\^$y/3, e$_3$=0.53 and e$_4$=0.83, K$_3$=0.$\^$d/0585 and K$_4$=0.$\^$d/0045, respectively. The analysis of the radial velocities of AH Cep published so far, do not conflict with the hypothesis of the multiplicity of the system but their accuracies are not high enough to be useful to support the interpretation. Other properties of the distant bodies are discussed for assorted possible inclinations of their orbits.