Four decades ago, the laboratory was arguably the preeminent particle physics laboratory in the world. In a straight tube two miles long, SLAC’s linear accelerator sped electrons to near the speed of light and slammed them together, generating insights into the smallest bits of matter.
In 1974, particles created at the accelerator confirmed the existence of the charm quark, an achievement that earned the team’s leader, Burton Richter, a Nobel Prize in Physics two years later. (Dr. Richter shared the honor with Samuel Ting of Brookhaven National Laboratory, which independently discovered the charm-containing particles at the same time.)
But higher energy accelerators were built elsewhere, and particle physics preeminence passed on, first to the Fermi National Accelerator Laboratory outside Chicago and now to CERN in Switzerland.
“We still are very strong in particle physics,” said Persis S. Drell, SLAC’s director, “but not like we were. We aren’t the center of the universe any more.”
The linear accelerator — the same one that discovered the charm quarks, now more than 40 years old — still accelerates electrons, but now as part of the X-ray laser. Instead of the electrons being directed onto a collision course at near-light speeds, they slalom through sinuous magnetic fields. As the electrons wiggle, they emit X-rays, and with precise wiggling, the X-rays coalesce into a laser beam.
It certainly is a drastic makeover of a very prestigious laboratory. The same type of fate, although not as drastic, may be faced by Fermilab with the Tevatron scheduled to reach its end in a year or two. While Project X may allow it to continue almost the way it is, the lab is also slowly transforming itself more into a neutrino source and research facility, which might be a brilliant move. With the ILC undergoing a slow death and almost on its last breath, the future of high energy physics experiment in the US faces a very uncertain future.