Long-term luminosity variations and period changes in CG Cygni


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Afsar A. , HECKERT R., IBANOGLU C.

ASTRONOMY & ASTROPHYSICS, cilt.420, ss.595-604, 2004 (SCI İndekslerine Giren Dergi)

  • Cilt numarası: 420 Konu: 2
  • Basım Tarihi: 2004
  • Doi Numarası: 10.1051/0004-6361:20040115
  • Dergi Adı: ASTRONOMY & ASTROPHYSICS
  • Sayfa Sayısı: ss.595-604

Özet

We report new photometry of CG Cyg from 1998-2002. We also analyze published photometry collected since 1965. An O-C analysis reveals evidence of a third body in the system having a 51 year orbital period. After removing the effects of the third body, we note a remaining 22.5 year cyclic variation in the O-C curve that is similar to the period of the luminosity variations. Modeling the spot activity for 28 V band light curves obtained between 1965 and 2002 confirms the presence of two active longitude belts (ALBs) at approximately 90degrees and 270degrees. Most of the spots occur at mid latitudes with a few at low latitudes. We note no spots at latitudes greater than 60degrees.