A PERIOD STUDY OF XZ ANDROMEDAE

DEMIRCAN O., AKALIN A., SELAM S. O., DERMAN E., MUYESSEROGLU Z.

ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES, cilt.114, sa.1, ss.167-170, 1995 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 114 Sayı: 1
  • Basım Tarihi: 1995
  • Dergi Adı: ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED)
  • Sayfa Sayıları: ss.167-170
  • Anahtar Kelimeler: STARS, XZ AND, ECLIPSING BINARIES, ACTIVITY, BINARY STARS, EPHEMERIDES, SYSTEMS, CYCLES
  • Ankara Üniversitesi Adresli: Evet

Özet

A period study of an evolved Algol system XZ And has been attempted by using additional new data. The (O-C) diagram formed by the times of minimum light and thus orbital period of the system was found explainable in terms of the beat effect of two (or possibly three) cyclic variations differing in periods (P-1=137.5 yr, P-2=36.8 yr, and P-3=11.2 yr) and amplitudes. We examined three possible explanatory mechanisms (apsidal motion of the slightly elliptical orbit, light time effect due to additional objects in the system, and the period modulation due to magnetic activity cycle of cool secondary component star). The observational evidences reject the possibility of apsidal motion effect on the period variation. One of the cyclic effects (probably with the shortest period P-3=11.2 yr) may be related with the cyclic magnetic activity of the secondary component. The third body hypothesis requires one or two under-luminous stars (with total mass of about 3 M.) around the system.