William Wolf

Postdoc Rsrch Assoc FSC 2008
TEMPE Campus


I grew up in rural Illinois and have long had an interest for Astronomy and a proclivity for math and science. After completing my undergraduate degrees in mathematics and physics at Eastern Illinois University, moved to the West coast to start a Ph. D. in the Physics department at the University of California Santa Barbara. There I began working with my advisor, Lars Bildsten. I focused my studies on thermonuclear burning on hydrogen-accreting white dwarfs, using the open source one dimensional stellar evolution code Modules for Experiments in Stellar Astrophysics (MESA).

As my dissertation project, I worked to characterize the different outcomes of hydrogen accretion onto a white dwarf star. At slow enough accretion rates, hydrogn accumulates until pressure at the base of the accumulated layer becomes high enough to initiate unstable nuclear burning, leading to a thermonuclear runaway and a luminous transient event known as a nova. At relatively high rates of accretion, the matter can be burned at the same rate is accreted, resulting in a hot, compact source of soft X-rays. At higher rates still, the star cannot burn the accreted material fast enough, and it instead forms an extended envelope, essentially reversing the planetary nebula phase of stellar evolution.

I built upon my work of soft X-ray sources and explored how novae, after their initial optical outburst, go through a short (days to years) phase where they behave like their steadily burning counterparts. I identified a relationship between the observable characteristics of this phase (duration and effective temperature) to the underlying white dwarf mass, providing another tool to infer white dwarf properties from post-nova observations. An undergraduate student, Tim Cunningham, and I then used this phase to help explain post-outburst radio emission as being driven by photoionization heating from the supersoft source.

I continue to work on accreting white dwarfs and development of MESA as a postdoctoral scholar in the School of Earth and Space Exploration at ASU under the supervision of Frank Timmes.


2010-2017: Ph. D. in Physics from University of California Santa Barbara

  • Advisor: Professor Lars Bildsten
  • Dissertation: Supersoft Emission from Thermonuclear Burning on Hydrogen-Accreting White Dwarfs 

2006-2010: B.A. in Mathematics and B.S. in Physics from Eastern Illinois University

  • Summa Cum Laude, University Honors, Presidential Scholar
  • Departmental Honors in Mathematics
    • Advisor: Leo Comerford
    • Thesis: Conjugacy in Hyperbolic Groups

Research Interests

  • Stellar Structure and Evolution
  • Accreting White Dwarf Stars
  • Stellar Explosions