Washington

A klystron such as this would accelerate high-energy microwaves for the planned linear collider. Credit: SLAC

The construction of a linear electron–positron collider should be the top priority for high-energy physics over the next 20 years, an advisory panel has told the US government.

The panel, a sub-group of the High Energy Physics Advisory Panel that is chaired by Jon Bagger of Johns Hopkins University, also recommends that the United States should seek to host the collider.

But if it is built, the machine will cost between $5 billion and $7 billion, and will require strong collaboration between physicists in Japan, the United States and Europe. It remains unclear what form that collaboration will take.

So far, regional groups of physicists have done most of the conceptual design work on the collider, and Bagger says that an international organization is needed “almost immediately” to improve the way these efforts are coordinated.

“The international community has to get its act together,” agrees Albrecht Wagner, director of DESY, Germany's high-energy physics research centre in Hamburg. He adds that any collaboration will face tough choices about where to build the machine and which technologies to use.

US high-energy physicists acknowledge that they face an uphill struggle in convincing the Department of Energy and the National Science Foundation, the agencies that support their discipline, to back the project. But Bagger is hopeful. “A 10–30% increase in our budget would do the job,” he says. “That's not unreasonable to contemplate.”