HRD for massive pop III stars


The Hertzsprung-Russell diagram (HRD) is a classic tool of astronomers used to investigate how stars evolve. My figure above shows the evolution in the HRD of models of high mass Population III stars. These are the first stars formed after the Big Bang and contain virtually no heavy elements. They are believed to be responsible for re-ionization of the Universe after the Dark Ages. Population III stars have not yet been observed but their detection is a goal of the James Webb Space Telescope.

My office is Room 270 in Sharp Lab. The best way to contact me is by e-mail to You can try to phone me at 302-831-6855 or write to me at 104 The Green, Newark DE 19716.


I am an astrophysicist who is primarily interested in computer modelling of stars. Recent research has focused on how a star's magnetic field influences its structure and evolution.


In Spring 2020, I'm teaching PHYS425 Quantum Mechanics II.


At the departmental level, I serve as the Associate Chair. I am Deputy Director of the Delaware Space Grant Consortium.  .