Previous abstract Next abstract

Session 81 - Variable Cool and Late Type Stars.
Display session, Wednesday, January 15
Metropolitan Ballroom,

[81.06] Studies of Large-amplitude Delta Scuti Variables: DY Pegasi

W. J. F. Wilson, E. F. Milone, D. J. I. Fry (RAO, U. Calgary)

It is a desirable goal to determine the Baade-Wesselink radii and luminosities a large number of delta Scuti pulsating stars, to explore their limitations as standard candles. This is the third system (after EH Lib and DY Her) which we have modeled.

In a modest contribution to this goal, we have determined a Baade-Wesselink radius for the large-amplitude delta Scuti variable DY Pegasi using Fourier representations of our observed BVI light curves and cross-correlated radial velocity curve. We have combined the B, V, and I flux curves with the B-V, B-I, and V-I color index curves and the radial velocity curve to obtain six independent radius determinations, yielding a mean value of the minimum radius of Rmin = 2.3 +- 0.3 Rsun. We are in the process of reducing infrared J and H data, and will incorporate these into the analysis in the near future in the hope of improving the accuracy of the radius determination by extending the color index baseline.

This work has been supported by grants to EFM from NSERC of Canada and by the Department of Physics and Astronomy, University of Calgary.

Program listing for Wednesday