Associate Professor
Ph.D., Astrophysics, University of California at San Diego 1990
Contact Information
Department of Physics and Astronomy
University of Iowa, 707 Van Allen Hall
Phone: 319-335-3282, FAX: 319-335-1753
Email: kenneth-gayley [at] uiowa.edu
Personal home page: http://astro.physics.uiowa.edu/~kgg
Biographical Information
I grew up in Buffalo, N.Y.,and attended Princeton University (A.B. Physics, 1983). I went on to study solar physics at U. C. San Diego and at the Institute for Astronomy in Honolulu. After one post-doc in cool star spectroscopy at the University of Colorado and another in hot-star wind dynamics at the University of Delaware, I joined the faculty at the U. of Iowa in 1997. On the personal side, I have long enjoyed playing Ultimate frisbee, but starting a family has more recently dominated my activities away from work.
Research Interests
My current research interests center on radiative transfer in stellar atmospheres, primarily the supersonic winds of very hot stars where the radiation is actually the dominant driver of mass motions. The Sun has a wind too, but on the scale of a hot star it is like a drippy faucet compared to the Niagara Falls! Hot stars are continuously experiencing the stripping of their outer layers, and in some cases lose a significant amount of their mass over their evolutionary lifetime. I also study binary hot stars and the violent collisions of their winds.
Recently I have extended my interests to the X-rays emitted by these violent collisions, eitherbetween winds or within individual winds. The usual approach to doing this is to try to infer the distribution of hot gas that generates the X-rays, but I prefer to try to model the heating process directly, rather than via its hot-gas middleman, because I have found that the hot gas distribution cannot be known unambiguously, and in any event it is the heating we wish to understand.I also model the circularly polarized spectra of winds threaded with strong magnetic fields, as the magnetic fields can play a role in causing wind streams to collide.
The unifying thread throughout my interests is the way we use light to learn about astrophysical phenomena, and my approach is generally to fill what I perceive is an important niche that connects the qualitative and conceptual features between both models and observations. I feel this kind of bridging brings insight and clearer communication across the divide between these often rather disparate disciplines, a bridge that can get lost in those devilish details.
Selected Publications
Gayley, K, and Ignace, R. 2010, The Zeeman Effect in the Sobolev Approximation: Split Monopole Fields and the "Heartbeat" Stokes V Profile, ApJ, 708,615.
Jaeger, T., Mutel, R., and Gayley, K. 2010, Project RESUN, a Radio EVLA Search for UHE Neutrinos, Astroparticle Physics, doi:10.1016/j.physletb.2003.10.071
Gayley, K. G., Mutel, R. L., & Jaeger, T. R. 2009, Astrophysical Journal, Analytic Aperture Calculation and Scaling Laws for Radio Detection of Lunar-Target UHE Neutrinos, 706, 1556.
Gayley, K. G. 2009, Asymptotic Opening Angles for Colliding-Wind Bow Shocks: The Characteristic-Angle Approximation, ApJ, 703,89.
Tuthill, P., Monnier, J., Lawrance, N., DAnchi, W., Owicki, S., Gayley, K. 2008, The Prototype Colliding-Wind Pinwheel WR 104, ApJ 675, 698.