'X' marks Fermilab future

Fermilab is floating plans for a new $500 million particle accelerator in hopes of paving the way for a much larger project and shoring up the lab's fragile position in the world of high-energy physics.

A road map for the machine, dubbed "Project X" for now, was quietly disclosed last week in the lab's daily newsletter. The new device would become the biggest project at the Batavia facility after the scheduled shutdown in 2009 of the Tevatron, currently the world's most powerful accelerator studying the fundamental structure of the universe.

Fermilab's long-range ambition is to host a mammoth project called the International Linear Collider, but that idea will take decades to bring to fruition. Project X would incorporate many of the technologies needed for the ILC, yielding new experimental opportunities and potentially strengthening Fermilab's chances of landing the bigger device.

"This would be a world-class machine at a cost that is much lower than the ILC," said Fermilab Director Pier Oddone.

If Project X is ultimately approved, construction probably would not begin until 2010 or later, experts said.

Securing such a substantial project would help address a looming crisis for Fermilab. The 40-year-old lab is hunting for a mission to keep it vibrant after the scheduled start-up next year of a European accelerator, the Large Hadron Collider, which will supersede the Tevatron as the world's premier high-energy physics instrument.

Replacing the Tevatron's central role at Fermilab won't be quick or easy.

The international physics community has agreed that the next logical step after the European collider would be the ILC, envisioned as a 20-mile gun barrel to speed up and smash together electrons and their antimatter counterparts, called positrons. The ILC, which could end up costing anywhere from $15 billion to $28 billion, would build on findings from the European collider, including the potential discovery of the Higgs boson, a key particle thought to impart mass to all matter.

But the ILC's daunting cost and the involvement of many nations could make for a drawn-out approval process. Even then, the collider may end up being built in Europe or Asia. In February, U.S. Department of Energy Undersecretary Raymond Orbach, who oversees the high-energy science program that includes Fermilab, signaled that the ILC may not be ready until the late 2020s. He urged the U.S. physics community to consider other ways of making fundamental discoveries in the meantime.

If the ILC approval process drags out, Project X could be just the steppingstone Fermilab needs. It would consist of a linear accelerator that Oddone described as akin to the "front end" of the ILC. The device would shoot protons into the Main Injector, an existing circular accelerator at Fermilab. It would also provide a powerful source of neutrinos, mysterious particles that may offer insight into how matter formed at the dawn of the universe.

Building Project X also could give U.S. industrial suppliers important experience in making sophisticated superconducting devices needed for the ILC.

"If we build this, we're actually reducing all the risks involved in building the ILC," Oddone said.

The first step will be securing funding for research and development on Project X. Evaluating the project's merits will fall to a national physics advisory group called P5, led by physicist Abe Seiden of the University of California at Santa Cruz. Seiden said that although it would not make sense to do Project X and the ILC at the same time, the smaller project could be worth it if the ILC gets delayed.

"It's a tricky situation," Seiden said. "It may be wise at first to do a less expensive project that still does very good physics."

But embracing the project may have a downside for Fermilab.

One document on the Web site of the Fermilab Steering Group, which drew up the plans for Project X, listed as a potential concern the effect such a project might have on "international perception about [Fermilab] and the U.S.'s commitment on ILC."

The fear is that other countries will think the U.S. wants to do Project X instead of the ILC or has lost enthusiasm for the larger project.

"That's emphatically not the case," said Fermilab spokeswoman Judy Jackson. "We're doing this along the road to the ILC. But we also have to allow for the possibility that the ILC will take longer than everyone hopes."

Seiden's physics advisory group will begin evaluating Project X in September and may decide on funding for the research and development phase by early next year. Experts said a decision on whether to build the project probably won't happen until at least 2010, when the timeline for the ILC should be clearer.

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