Each of the labs has a unique case to make: A 2007 long-range plan drafted by NSAC, for instance, highlighted the Jefferson Lab upgrade as the top priority for U.S. nuclear physics. That upgrade, which will double the energy of the electron beams in the lab's particle accelerator, is roughly two thirds complete, says Robert McKeown, deputy director for science at Jefferson Lab. And the machine already has seven to 10 years of experiments queued up for when it returns to active service sometime after 2015. The Jefferson accelerator explores several questions relating to the structure of the atomic nucleus, including how the fundamental particles of matter, quarks and gluons are bound up inside protons and neutrons. The lab received about $160 million this year from the DoE, including $50 million in construction funds for the facility upgrade.
Unlike Brookhaven, which hosts a number of large experiments, Jefferson Lab would essentially cease to exist if its accelerator were defunded. "We're a single-purpose laboratory," McKeown says. "So the situation would be very different for us if the decision were made not to continue our electron accelerator." Some 700 jobs depend on the lab's continued operation.
Michigan State University's planned FRIB (pronounced "eff-rib"), earned the second-highest slot in the 2007 ranking of nuclear physics priorities. The machine would produce on demand a variety of exotic isotopes—often unstable versions of chemical elements with abnormal numbers of neutrons in the nucleus. FRIB would investigate the origins of the elements that constitute our physical world, many of which are born in the cores of stars and in supernova explosions, and could quickly churn out isotopes for medical research and the development of advanced imaging technologies.
The facility is still in the design phase, and though the DoE has not issued formal schedule and budget, preliminary estimates peg FRIB as a 10-year project costing more than $600 million. Once built, however, its operations costs would potentially be lower than those of either Jefferson Lab or RHIC, and its staff would be much smaller. "But being the cheapest may not really be germane here," says FRIB project manager Thomas Glasmacher, a nuclear physicist at Michigan State. "It's kind of like comparing apples and eggs or something like that. It's different science, and they're different experiments."
In interviews, the three lab representatives took pains not to disparage the other facilities, choosing instead to highlight the upsides of their own respective experiments. "We are all on each other's advisory committees," Glasmacher says. "It's a very small community." All three facilities are highly touted and in high demand—even FRIB, which will not exist for many years under the best of circumstances, already has more than 1,000 scientists signed on to its user group.
Shuttering any of those projects will disrupt a field in which, as McKeown puts it, "the U.S. maintains the frontier facilities and has substantial leadership throughout the world." It falls to the Tribble panel to choose which of three unpalatable options is the least so. "I don't envy anybody on the panel," Glasmacher says.
Brookhaven's Vigdor echoes that sentiment. "It’s hard to predict how things are going to come out, because there are no easy solutions right now," he says. "Every possible solution carries a lot of pain."