My research is centered on the origin and evolution of the chemical elements between C and Fe on the periodic table. My projects fall within three specific areas: 1) the chemical evolution of C, N, and O in disk galaxies and damped Lyman alpha systems; 2) the abundances of C, N, O, in planetary nebulae and the contribution of intermediate and low mass stars to galactic chemical evolution; and 3) the evolution and spatial distribution of alpha element abundances in disk galaxies using probes such as H II regions and planetary nebulae. Collaborators include Karen Kwitter (Williams College), Bruce Balick (U. Washington), Jackie Milingo (Gettysburg College), Reggie Dufour (Rice University), and Jason Prochaska (UCSC).


Jim Buell, Abundances in Planetary Nebulae, 1997. Currently, Associate Professor, Department of Physics, Alfred State College.

Tad Thurston, The  Abundance and Chemical Evolution of Nitrogen in Spiral Galaxies, 1998. Currently, Professor of Physics, Oklahoma City Community College.

Joe Howard, Prospecting for Elements: Galactic Halo Planetary Nebulae Abundances and Virgo Spiral Galaxy Color Profiles, 1998.  Currently, Associate Professor and Chair, Department of Physics, Salisbury University.

Jackie Milingo, Abundances of Sulfur in the Milky Way Disk from Peimbert Type II Planetary Nebulae, 2000. Currently, Associate Professor, Department of Physics, Gettysburg College.

Aida Wofford (nee Nava), Is the Scatter in N/O of Metal-Poor Systems Real? Do H II Regions Become Significantly Self-Enriched in O?, 2008. Currently, Postdoctoral Fellow, Space Telescope Science Institute.