CAMBRIDGE, Mass.--MIT scientists and colleagues have successfully operated MIT's experimental nuclear fusion reactor over the Internet from California.
This is the first trans-continental operation of a fusion reactor, or tokamak, an important step because future tokamaks will be national or international facilities. The March 28 demonstration, funded by the Department of Energy (DOE), shows that scientists could run tokamak experiments from their home labs. This would cut costs such as travel and housing for visiting scientists.
The MIT tokamak in Cambridge, Alcator C-Mod, was operated by MIT scientists from Lawrence Livermore National Laboratory in California over a Department of Energy (DOE) "subnet" of the global Internet. The Energy Science Network (ESnet) is dedicated to energy research. The scientists ran a few tests over ESnet two weeks ago, but yesterday (March 28) marked the first full day of experiments.
Tokamaks are machines that make plasma, an electrically charged gas that can be used to achieve nuclear fusion. "The purpose of our research is to understand the behavior of extremely high-temperature plasmas, with the ultimate goal of making nuclear fusion into a commercial energy source," said Earl Marmar, a senior research scientist in physics and a member of the tokamak team at MIT's Plasma Fusion Center (PFC).
In the experiments conducted over the Internet, the scientists used the reactor to create plasma in one-second bursts every 15 minutes. Each experiment involves a physics operator ("the person who chooses the parameters of each plasma shot," Dr. Marmar said) and a session leader (the scientist in charge of the experiment).
For the Internet experiments, both of these scientists were based in California. Brian LaBombard was the session leader, while Steve Horne was the physics operator (Drs. LaBombard and Horne are experimental research scientists at the PFC). They were able to communicate with their Cambridge-based colleagues via live audio and video over the Internet.
Dr. Marmar noted, however, that the engineering systems that ensure the safety of the tokamak are still operated locally at MIT. "The engineering systems can't be done remotely, and we wouldn't want them to be done remotely," he said. "The engineers at MIT have ultimate control to ensure that everything's operated safely." For example, they can make sure that currents aren't too high, which could damage the tokamak's magnets.
MIT's Alcator C-Mod is one of three major test reactors in the United States (the others are at Princeton and in San Diego). Future national or international facilities include the Tokamak Physics Experiment (TPX) that would be sited at Princeton, and the International Thermonuclear Experimental Reactor (ITER) that is being designed as a collaboration among the United States, Europe, Japan, and Russia. (It is not yet clear where ITER will be built.)
The current tests over the Internet are proving the technical feasibility of running a tokamak remotely. But equally important, they are also allowing the scientists to learn more about how to manage groups of people who are not in the same place. "We're kind of dipping our toes into both technical and collaboration issues," said Martin Greenwald, a PFC principal research scientist and head of the PFC's Office of Computer Services.
Other MIT scientists involved in the experiment are Systems Programmer Josh Stillerman and Principal Research Scientist Yuichi Takase at Livermore, and Systems Programmer Ian Fredian at MIT. Lawrence Livermore scientists who were involved in the work include Tom Casper, Jeff Moller, and Bill Meyer. Additional collaborators were from the University of Maryland and Johns Hopkins University.
Professor Ian Hutchinson of the MIT Department of Nuclear Engineering is principal investigator for Alcator C-Mod experiments.