The photometric-amplitude and mass-ratio distributions of contact binary stars

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

AASTeX5, 12 figures, 5 tables, accepted by AJ, Aug.2001

Scientific paper

10.1086/321153

The distribution of the light-variation amplitudes, A(a), in addition to determining the number of undiscovered contact binary systems falling below photometric detection thresholds and thus lost to statistics, can serve as a tool in determination of the mass-ratio distribution, Q(q), which is very important for understanding of the evolution of contact binaries. Calculations of the expected A(a) show that it tends to converge to a mass-ratio dependent constant value for a->0. Strong dependence of A(a) on Q(q) can be used to determine the latter distribution, but the technique is limited by the presence of unresolved visual companions and by blending in crowded areas of the sky. The bright-star sample to 7.5 magnitude is too small for an application of the technique while the the Baade's Window sample from the OGLE project may suffer stronger blending; thus the present results are preliminary and illustrative only. Estimates based on the Baade's Window data from the OGLE project, for amplitudes a>0.3 mag. where the statistics appear to be complete allowing determination of Q(q) over 0.120. The mass-ratio distribution can be approximated by a power law, either Q(q)~(1-q)^a1 with a1=6+/-2 or Q(q)~q^b1, with b1=-2+/-0.5, with a slight preference for the former form. Both forms must be modified by the theoretically expected cut-off caused by a tidal instability at about q_min 0.07-0.1. An expected maximum in Q(q), is expected to be mapped into a local maximum in A(a) around 0.2-0.25 mag.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

The photometric-amplitude and mass-ratio distributions of contact binary 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 The photometric-amplitude and mass-ratio distributions of contact binary stars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The photometric-amplitude and mass-ratio distributions of contact binary stars will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-287633

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.