U.S. science budget. Bigger contribution to ITER erodes domestic fusion program.

C R E D IT : P A U L R IV E N B E R G /M . P . M C N A L L Y The U.S. fusion program is in a bind. To remain at the cutting edge, U.S. fusion researchers must participate in the huge international experiment called ITER being built in Cadarache, France. But to pay for ITER— which aims to produce a self-sustaining fusion reaction, or “burning plasma,” and prove that fusion is a viable energy source—the United States may have to sacrifi ce the very community of researchers who would use the machine when it is ready. That paradox hit home last week, when President Barack Obama submitted a 2013 budget request to Congress that would slash the nation’s already beleaguered domestic fusion program while boosting the U.S. contribution to ITER. Contributing to ITER “is reasonable only in the context of a domestic program,” says Martin Greenwald, a physicist at the Massachusetts Institute of Technology (MIT) in Cambridge and chair of the Department of Energy’s (DOE’s) Fusion Energy Sciences Advisory Committee (FESAC). “Otherwise, you’re just building a piece of equipment for other people to use.” At fi rst blush, the proposed 2013 budget for the fusion energy sciences program at DOE doesn’t look so bad. It would dip by less than 1% to $398 million. However, within that fl at budget, spending on ITER construction would increase by 43% next year, from $105 million to $150 million. As a result, spending on fusion research at home would fall 16%, to $248 million. The effects of the cut would be dramatic. DOE supports three large experimental devices called tokamaks—doughnut-shaped chambers in which ionized gas, or “plasma,” is confined by magnetic fields and heated and squeezed to the point at which atomic nuclei fuse and release energy. In the biggest blow, the tokamak at MIT, called the Alcator C-Mod, would shut down. “I was shocked,” says Miklos Porkolab, director of MIT’s Plasma Science and Fusion Center. “I didn’t have the vaguest idea of what was coming.” C-Mod is the only U.S. tokamak that operates at magnetic fi elds as strong as ITER’s will be, Porkolab says. It supports 100 staff members and 30 graduate students. The budget of the United States’s sole dedicated fusion lab, the Princeton Plasma Physics Laboratory (PPPL) in New Jersey, would drop by 16%, to $61.8 million. “If all the cuts go through, we would have to lay off about 100 of 435 staff,” says PPPL Director Stewart Prager, who notes that the lab has already shrunk by two-thirds since the 1990s. The proposed cut for 2013 would stretch by 6 months an on going upgrade of the lab’s National Spherical Torus Experiment, delaying the tokamak’s restart until 2015. Obama’s budget request, if adopted by Congress, would leave the United States with only one tokamak operating next year, the DIII-D at General Atomics in San Diego, California. But its running time would be reduced to 10 weeks—3 weeks less than this year and a far cry from the 25 weeks that would con-