Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-07-09
Astronomy and Astrophysics
Astrophysics
Accepted for A&A; 11 pages, 9 figures
Scientific paper
10.1051/0004-6361:20052805
Complex period variations of five W UMa type binaries (AB And, OO Aql, DK Cyg, V566 Oph, U Peg) were investigated by analyzing their O--C diagrams, and several common features were found. Four of the five systems show secular period variations at a constant rate on the order of |dP / dt 1/P | ~ 10E-7 1/yr. In the case of AB And, OO Aql, and U Peg a high-amplitude, nearly one-century long quasi-sinusoidal pattern was also found. It might be explained as light-time effect, or by some magnetic phenomena, although the mathematical, and consequently the physical, parameters of these fits are very problematic, as the obtained periods are very close to the length of the total data range. The most interesting feature of the studied O--C diagrams is a low amplitude (2-4 x 10E-3 d) modulation with a period around 18--20 yr in four of the five cases. This phenomenon might be indirect evidence of some magnetic cycle in late-type overcontact binaries as an analog to the observed activity cycles in RS CVn systems.
Biro Imre Barna
Borkovits Tamás
Csizmadia Sz.
Csorvasi R.
Elkhateeb M. M.
No associations
LandOfFree
Indirect evidence for short period magnetic cycles in W UMa stars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Indirect evidence for short period magnetic cycles in W UMa stars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Indirect evidence for short period magnetic cycles in W UMa stars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-403439