Department of Physics and Astronomy
Office: ABB 353
Phone: (905) 525-9140 x24189
FAX: (905) 546-1252
Research Area: Astrophysics
In my research, I use knowledge of stars and stellar evolution to understand
unusual stars in dense places, their interactions and their effect on their
A selection of questions that my group is interested in:
- Stellar Collisions:
- Are collisions between giant branch stars and something else
responsible for extreme horizontal branch stars in globular
clusters? Are they responsible for the colour gradients in
post-core collapse clusters? What about low mass helium
- What are the surface abundances of the product of main
sequence -- main sequence star collisions?
- What happens to the angular momentum in a stellar collision
and during the subsequent evolution of the product?
- Globular Cluster Formation and Dynamics:
- What do the blue straggler populations in globular clusters
tell us about the dynamical history of the cluster?
- Did the stars in globular clusters form all at once, or was
there more than one burst? Can we discover that dynamically?
- What effect, if any, does dark matter have on the formation
of globular clusters and dwarf galaxies?
- Contact Binary Stars
- How do binary stars merge? What is the structure of the resulting star?
What are its rotation properties? What do the resulting blue stragglers
- What happens to the structure of low mass stars when they lose mass
through transfer onto a binary companion?
- Stars with Planets
- Detailed characterization of stars with planets.
I answer these questions using a variety of theoretical techniques and
computer codes. Depending on the situation, I use stellar evolution
codes, smoothed particle hydrodynamic codes or stellar dynamics codes,
running on computers which range from the PC sitting on my desk to
supercomputers. I also own one of the world's fastest computers, a
GRAPE, for stellar dynamics work. This computer is hard-wired to
calculate the gravitational force between many many stars very
quickly, and allows us to look at the dynamics in globular clusters on
a reasonable time.
I am an active member of collaborations with researchers from Canada, the US
and Europe, especially the MODEST
(MOdelling DEnse STellar Systems) collaboration.
Publications from ADS Abstract Service
of Physics and Astronomy Home Page