Physicists dream of next big particle smasher

SAN FRANCISCO, Feb 18 (Reuters) As the world's largest particle collider being completed on the French-Swiss border prepares for its first test in November, scientists are already looking at building the next big particle-smashing machine.

The Large Hadron Collider, a project 13 years in the making, should be completed in August and start operating at a low energy level by the end of this year, said Philip Bryant, a scientist at CERN, the European Organisation for Nuclear Research.

''By mid-2008, we should start doing physics,'' Bryant said at the annual meeting of the American Association for the Advancement of Science in San Francisco.

The huge circular tunnel -- 17 miles (27 km) in circumference -- is designed to smash protons into each other at extremely high speeds trying to replicate in miniature the events of the Big Bang.

Physicists hope the particle collider, known as LHC, will answer crucial questions such as how matter was created and what gives mass to matter.

Yet even before the first proton collides with another, physicists are dreaming up the next big machine, this one an International Linear Collider that would give physicists a more refined tool for exploring the mysteries of the universe.

''This will not have more power (than LHC), but more precision,'' said Jonathan Bagger of Johns Hopkins University in Baltimore.

The International Linear Collider would consist of two 12- mile (20-km) linear accelerators lined up face to face that would shoot some 10 billion electrons and their anti-particles, positrons, toward each other at nearly the speed of light.

The straight-line collider would eliminate some of the energy wasted in the circular electron accelerators, allowing physicists to see new particles in unprecedented detail.

The collision of those beams would create an array of new particles. Bagger said he was eager to find what can be learned by the ''crisp, precise beams of this machine.'' 'FIRST GLOBAL ACCELERATOR' The Intergradational Linear Collider, proposed by physicists from Europe, Asia and the Americas, is still in the its planning stages and does not yet have a home.

''This machine will really be the first global accelerator,'' Bagger said.

At a projected cost of nearly 7 billion dollars, a lot is riding on funding, something that appears to be in short supply.

Nobel laureate Burton Richter of Stanford University, speaking in a panel on the future of particle physics at the meeting, sounded alarm at the apparent lack of funding for such super-colliding machines.

''We're in the middle of a particle physics revolution,'' Richter said.

''The next 10 to 15 years will answer many questions and raise new ones,'' Richter said. ''Regrettably, the experiments are bigger and more expensive ... so finance will limit the pace of discovery.'' Richter said the International Linear Collider could be operational in 2012, provided it won enough international support.

REUTERS PB HS0834