The MEDUSA (=Madison EDUcational Small Aspect-ratio) Tokamak is a low-aspect ratio tokamak built and designed almost entirely by students, primarily undergraduates, at the University of Wisconsin Madison Nuclear Engineering & Engineering Physics department under the guidance of Dr. Raymond Fonck. Its purpose is to probe low aspect ratio tokamak performance for fusion energy research and plasma physics applications. A tokamak like MEDUSA is a magnetic bottle designed to hold plasmas at the very high temperatures required for fusion energy. For those who haven't had previous experience with fusion energy, the lab a General Atomics has put together a slide show that explains the basics as well as a page of term definitions, and another page here gives you an introduction to what a Tokamak is.

Where We Are Now:

  1. Some time in the 21st Century, we will need a new primary energy source, despite gains in efficiency:
  2. Magnetic Confinement Fusion may provide an alternative, but current-technology reactors would be:
  3. We need a fusion concept which is:
MEDUSA is part of a generation of machines designed to address advanced Tokamak design issues that may achieve these goals.


With an aspect ratio (major/minor radius) of 1.5, MEDUSA is one of approximately 6 low aspect ratio Tokamaks in operation. The low aspect-ratio concept has a number of advantages that make it a promising approach to advanced tokamak design, which MEDUSA is designed to probe.
  1. Physical Specifications:
    Cross-sectional drawing of MEDUSA

  2. Diagnostics:
  3. Machine Performance:
    False color image of MEDUSA plasma

  4. Research Concentrations
  5. The Next Step: Pegasus

Other Labs of Interest

Cameron Geddes/040795/
Greg Garstka / 6-14-96 /