A good BaBar gain

The BaBar experiment represents “a new mode of US experimentation”, said Stanford Linear Accelerator Center (SLAC) director Burt Richter at the experiment’s formal dedication on 13 August. BaBar is the detector at the heart of the recently commissioned PEP-II B-factory at SLAC, Stanford. Some 50% of the physicist participation and 40% of the hardware value come from outside the US.

Physicists habitually use an overstrike to denote an antiparticle. They talk about “p-bars” instead of antiprotons, and “B-bar” as the antiparticle of a B meson ­ hence BaBar, better known in certain circles as the friendly elephant in the stories by Jean de Brunhoff.

SLAC research director David Leith explained that BaBar is highly “non-SLACentric”, with a spokesman (David Hitlin of Caltech) who is elected rather than appointed. “We went to school at CERN to learn how to manage large international projects,” explained Leith.

SLAC, which was established to exploit the 2 mile linear electron accelerator, is no stranger to major projects. However, the more than 600 strong BaBar collaboration is the largest research group that SLAC has ever seen, with physicists from Canada, China, France, Germany, Italy, Norway, Russia and the UK, as well as the US.

The keynote speaker was director of the US Department of Energy’s Office of Research, Martha Krebs, who underlined the role of PEP-II and BaBar in current US particle physics research. After the demise of the superconducting supercollider in 1993, a “future visions” panel, chaired by Sid Drell of SLAC, foresaw a US programme with significant US participation in the LHC collider at CERN. Also included was the SLAC B-factory, initially green-lighted in the same wave of legislation that swamped the SSC.

Krebs went on to point out that no fewer than 8 of the 10 DOE labs in her portfolio had appointed new directors. She called for leadership during a difficult transition period.

In a recent hiccup, a US Senate subcommittee explicitly recommended a reduction in research and development spending for the Next Linear Collider (NLC), an electron­positron machine being touted around the Pacific Rim to attack the next energy frontier. While physicists are gung-ho about the need for such electron­positron machines to explore fully the immediate energy frontier, the move is redolent of the early 1990s disfavour in certain political quarters that eventually torpedoed the SSC. “In staying at the energy frontier,” said Krebs, “we cannot count on an orderly progression.”

“They are not as ready to proceed with the NLC as we are,” commented Richter, who stepped down as SLAC director at the end of August. He is succeeded by Jonathan Dorfan, formerly SLAC associate director and head of the PEP-II B-factory project. Richter becomes chairman of the International Union of Pure and Applied Physics. Krebs paid tribute to Richter’s exemplary role as a leader, both at SLAC and for the community.

The BaBar dedication fitted nicely into the programme for the International Lepton-Photon Symposium at Stanford.