This is a technical paper concerning the design and commissioning of a gamma ray camera on the DIII-D tokamak. The diagnostic, the Gamma Ray Imager (GRI), is a pinhole camera constructed of lead. This diagnostic is being used to study the behavior of relativistic electron beams in magnetically confined fusion plasmas. Gamma rays can be […]
Research
Exponential Frequency Spectrum and Lorentzian Pulses in Magnetized Plasmas
Sections Details and Download Previous Work Modeling Lorentzian Pulses What is the Relevance? This is a review of a paper recently published by my group. Here, the paper is paraphrased to reach a wider audience. The plasma physics community can read the original publication, so my goal is to provide an example of current plasma […]
Keeping Fusion Plasmas Hot
The following article first appeared as David C. Pace, William W. Heidbrink, and Michael A. Van Zeeland, “Keeping Fusion Plasmas Hot,” Physics Today 68, 34 (2015). In the article, we discuss interactions between high energy ions and electromagnetic waves in magnetically confined plasmas. These plasmas are produced in nuclear fusion reactors known as tokamaks. My research […]
Energetic ion transport by microturbulence is insignificant in tokamaks
This paper means a lot to me. It has both a technical side and an emotional side. The physics of this paper concerns how small scale turbulent fluctuations in the plasma (e.g., fluctuations of the plasma density) can affect the way that energetic ions move across the magnetic field. Fundamentally, the orbit size of these […]
Energetic Ion Loss Detector on the Alcator C-Mod Tokamak
This paper describes the Fast Ion Loss Detector (FILD) at the Alcator C-Mod tokamak. The FILD captures ions that are accelerated to high energies due to radio wave power injection into C-Mod. A couple of neat things about this diagnostic are that it is made of the same molybdenum material as the walls in C-Mod, and […]
Scrape-off layer ion acceleration during fast wave injection in the DIII-D tokamak
This paper describes observations of injected radio wave power getting absorbed by edge ions in the DIII-D tokamak. It’s a valuable observation because we inject those radio waves in order to heat the plasma more towards the center of the tokamak, so if some of that energy gets absorbed by particles in the far edge, then […]