Lisa M. Young's Research Projects
My research activities primarily focus on the interstellar medium (ISM)
and the structure of dwarf and elliptical galaxies. The big picture is
to tease out the evolution of galaxies by studying the interplay between
ISM and the rest of the galaxy. Specific questions which I am
investigating include the following:
Elliptical galaxies
- Some elliptical galaxies have significant amounts of cold
(molecular) gas. Did the molecular gas come from internal sources
or was it acquired from other galaxies? How long has the molecular
gas been there? Some clues to these questions come from a
comparison of stellar and gas kinematics.
- If the molecular gas serves as a tracer of the most recent
interaction or merger partner, it can be used to test theories of the
formation of boxy and disky ellipticals.
- For the unusually cold-gas-rich ellipticals, gas dynamics can be
used to find the intrinsic shapes and the mass distributions
(quantity/structure of dark matter). But are these cold-gas-rich
ellipticals representative of the general population of ellipticals?
- I am also searching for evidence of the growth of stellar disks
inside ellipticals. There's a press release.
Spiral galaxies
- How do galaxy interactions affect the star formation rates and
the distribution of star formation activity in early-type spirals?
- How do grazing interactions affect the phase structure of the ISM
in spirals?
Optical image (greyscale) and atomic hydrogen (HI) in NGC 3471 (Hameed
& Young 2003).
Dwarf galaxies
- I have also worked on the phase structure of the HI medium in
dwarf galaxies (cold neutral medium vs. warm neutral medium). How
do the mass fractions and the distributions of these phases compare to
theoretical models?
- How does the phase structure of the ISM influence star formation
activity?
- ...and vice versa: how
does the star formation activity influence the phase structure of the
ISM?
Students are welcome to inquire
about working with me on various observational projects which might
include optical imaging and spectroscopy or radio interferometry (HI and
CO).
Lisa Young's publications