March 19, 2004  


Report of the SLAC Scenarios Study Released

By Heather Rock Woods

For 40 years SLAC has hummed with scientific excitement day and night, and it will be no different in the year 2015.

Drawing Courtesy of Diana Rogers

That’s the conclusion of the newly released SLAC Scenarios Study, which examined what the Lab might look like in 2015 in the context of the huge international effort to build a new linear collider.

“The report shows SLAC is going to remain a vibrant place with a strong physics program,” said Tom Himel (NLC), who co-chaired the scenarios committee with Research Director Persis Drell.

“The pillars of the program are strong. The Lab is flexible, able to respond to new advances and surprising results that will unfold as the next decade progresses,” the report states. The committee made no recommendations on which scenarios to pursue—its job was to provide feasible options, not to produce a fixed road map.

High Energy Frontier

“The scenarios study is a tool management can use to plan how to get from where we are to where we want to be,” Himel said. Over the past year, the committee solicited opinions from SLAC users, staff and faculty in public seminars and at a Town Meeting. The committee worked on the baseline assumptions that the PEP-II/BaBar program has a strong future through 2010, that a linear collider will be built, that SSRL has a bright future with its SPEAR3 and x-ray laser (LCLS) programs, and that particle astrophysics will grow here under the auspices of the new Kavli Institute for Particle Astrophysics and Cosmology.

On the high energy frontier, all the scenarios include SLAC continuing to play a leadership role in the new linear collider, as well as sizably increasing the Lab’s advanced accelerator R&D aimed at making future machines both feasible and affordable. The linear accelerator (linac) remains a solid foundation in SLAC’s program under all scenarios, to be used for test beams and linear collider research, for advanced accelerator studies and for the upcoming x-ray laser. “The ubiquitous SLAC linac has enabled forefront science for 40 years on the SLAC site and is likely to do so for decades to come,” noted the report.

An interesting conclusion the committee drew was that, while the type of linear collider projects would change, the scope of SLAC’s on-site effort would basically be the same, whether the linear collider is built in the U.S. or elsewhere, no matter which technology is used to supply accelerating power. As builders of the world’s only linear collider to date, SLAC has vast experience, and believes that the X-band technology that it has developed in collaboration with KEK in Japan and other national and international partners is the best technology choice.

“This is an enormous project with room for SLAC leadership in many areas,” Himel said.

Flavor Physics Pillar

The biggest variation in the four scenarios is in the ‘Flavor Physics’ pillar. The current B Factory program (PEP-II/BaBar) runs through 2010. After that, the committee outlined different possibilities, including building a ‘Super’ B Factory here with massively better luminosity (based on ongoing accelerator R&D), making a lower-cost medium luminosity upgrade, helping Japan’s KEK lab upgrade their B machine, or ending the program.

The study also considered many opportunities for smaller high energy physics experiments. The scenarios committee had two sub-groups: one on linear collider options, co-chaired by Tor Raubenheimer (NLC) and Ewan Paterson (TD); and one on other physics options, co-chaired by Lance Dixon (THP) and John Seeman (AD). “We were pleased with the participation of the SLAC community in this process. I want to thank the committee for the wonderful job they’ve done over the last year,” Himel said.

To read the report, see:

You can also Town Meeting at:



The Stanford Linear Accelerator Center is managed by Stanford University for the US Department of Energy

Last update Thursday March 18, 2004 by Emily Ball