Selected Papers
Normal Modes of Oscillation for Rotating Stars III.
Variational Calculations with an Improved Set of Basis Vectors ,
ApJ, 301, 185-203, 1986.
Normal Modes of Oscillation for Rotating Stars IV.
Nonaxisymmetric Variational Solutions for 15 Solar Mass Models ,
ApJ, 339, 1022-1037, 1989.
Hydrodynamical Simulations of Rotating Stars I. A Model for
Sub-grid Scale Flow , ApJ, 406, 651-660, 1993.
Differential Rotation and the Convective Core Mass of Upper
Main Sequence Stars , ApJ, 420, 797-803, 1994.
Normal Modes of Oscillation for Rotating Stars V. A New Numerical
Method for Computing Nonradial Eigenfunctions , ApJ Suppl, 116,
57-74, 1998.
Current Work
At present, there is no method or numerical algorithm available for
solving exactly the stellar pulsation equations for rotationally
distorted models. That is, there is no theory of nonradial oscillations
of rapidly rotating stars that can be compared with the observations of
line-profile variables on the main sequence. Problems such as this
which involve partial differential equations with singularities at both
boundaries have resisted solution for many years. However, I have been
successful in developing a numerical scheme which solves the eigenvalue
problem on a 2D grid. The method is now being applied to the
computation of high radial order g-modes in slowly pulsating B stars
(5 solar mass). I am also interested in the low-order p-modes in
rapidly rotating models that might be observable in the near future from
space telescopes.
Another project is investigating nonradial oscillations of rapidly
rotating models with a 2D hydrodynamics code. This approach is still
very experimental and it is not clear where it will lead but I have been
successful so far in extracting low-order modes from a Fourier analysis
of the velocity fields. In the future, I want to study the effects of
rotation on chemical mixing and convection.