SLAC B-Factory resumes operations

After a nearly five-month shutdown, the B-Factory experiment at the Stanford Linear Accelerator Center (SLAC) is back online and ready to gather data.

SLAC Director Jonathan Dorfan suspended operations of all accelerators at the laboratory last October, when an electrical accident left a contract electrician seriously injured. The lab has since been working to address safety concerns raised by the Department of Energy's review board.

Dorfan assembled "validation teams" to ensure the safe restart of operations for the lab's major accelerator facilities. SPEAR3, SLAC's synchrotron radiation facility, completed its validation in January and was operational soon thereafter. The B-Factory's validation team approved the restart on March 24. Since then, the staff has been working hard to restore operations after the lengthy shutdown.

"I don't remember the last time the accelerator complex was off for this long," said David MacFarlane, spokesman for the BaBar detector, the main data-gathering component of the B-Factory. "Everyone involved with the B-Factory is excited to resume data collection."

But this excitement is tempered by a renewed commitment to safety at the lab.

According to John Seeman, head of SLAC's Accelerator Department, the B-Factory staff has updated key protocols and made several hardware upgrades to enhance safety. "We are thrilled to be up and running safely, starting to provide data to the BaBar detector."

The B-Factory, which includes the BaBar detector, the 2-mile-long linear accelerator and the PEP-II storage rings, is addressing some of the most perplexing questions in physics. Stated broadly, the experiment hopes to answer why matter won out over antimatter in the first few milliseconds following the Big Bang.

But the B-Factory is not the only experiment pursuing this goal. The Belle detector, at the Japanese National Laboratory for High-Energy Physics, has been collecting data while the BaBar detector sat idle.

"We've been watching the competition collect data steadily over the last five months," MacFarlane said. "Now that the B-Factory is running again, people are feeling much more upbeat."

MacFarlane said recent upgrades will eventually allow the B-Factory to collect data 40 percent faster than before. At this rate, the team should be able to double the total data set by next summer.

The first full test of the linear accelerator and the PEP-II rings took place on Saturday morning. The BaBar detector will follow suit early in the week, MacFarlane said. "Then we'll start taking data in earnest."

Matthew Early Wright is a science-writing intern at the Stanford Linear Accelerator Center.