September 3, 2004  


Director's Corner: SLAC Has a Unique Contribution to Make to International Linear Collider

By Jonathan Dorfan

As many of you know, the worldwide high energy physics community has reached an important milestone on the path to building an electron-positron linear collider, a facility that will unlock some of nature’s greatest mysteries.

Photo by Diana Rogers

The International Technology Recommendation Panel (ITRP), after eight months of very hard work, recommended on August 19th that superconducting (“cold”) technology, rather than conventional room temperature copper( “warm”) technology developed by SLAC and its Japanese partner KEK, be used for the linacs that will have to  accelerate the electrons and positrons to record energies of 500 GeV. ICFA, the International Committee on Future Accelerators, which was meeting in Beijing last week, unanimously accepted this recommendation and made it official.

The ITRP declared that both superconducting and room temperature technologies were viable and mature, and praised all the talented and dedicated teams which have worked on the research and development of these technologies for many years. A rational selection could not have been made unless both (and actually other variations of these) approaches had been carried forward to a mature point where an educated comparison was possible.   It is also important to understand that the ITRP recommended the cold technology, but did not recommend a specific design (such as the TESLA design by DESY, the German lab that developed the cold technology). The Panel also strongly recommended pooling the resources and know-how of the two groups, warm and cold, to produce the best possible new linear collider design.

The decision has significant implications for SLAC.  We are certainly disappointed that our warm technology was not selected. However, the high energy physics worldwide community has taken a huge and necessary step forward by making this selection, and has crossed a critical threshold in the realization of the dream that SLAC helped initiate—building a frontier energy linear collider.

Back row (left to right): FNAL Director Mike Whitherell, CERN Director General Robert Aymar, KEK Director Yoji Totsuka, Won Namkung (ALCSC), Brian Foster (ECFA), Giorgio Bellettini (ITRP), SLAC Director Jonathan Dorfan, Chen Hesheng, (IHEP Beijing), DESY Director Albrecht Wagner, Maury Tigner, (ILCSC) (Photo by Neil Calder)

The path forward is exciting and we remain an enthusiastic champion of the machine. As the only laboratory to have built a linear collider, the SLAC Linear Collider, we have expertise and experience in most areas critical to the linear collider design.  Our expertise and experience with the warm technology transfers naturally and powerfully onto the design based on cold cavities.

This multi-billion dollar machine can only happen if the three regions of the world (North America, Europe and Asia) come together and pool their human and fiscal resources.  We still have to take on tough technical and organizational issues to move the collaboration forward, to continue to show international commitment to the collider, so as to get the support of the many governments that are needed to fund the design and construction of the linear collider.

The International Linear Collider (ILC) is the new name for this bold global project. All previous names (NLC, JLC/GLC and TESLA) will be retired.  The ILC will be a complex machine with many different elements. It needs teams of people with broad expertise. The machine will have sources to produce electrons and positrons, damping rings to prepare the particle bunches, two main linear accelerators to accelerate the bunches, two final focus regions, the collision point where electrons and positrons smash into each other, and the detectors to record the collisions.

The assessment of our worldwide partners and the ITRP is unequivocal on one point: as we now form the International Linear Collider design effort, SLAC, because of its past experience and broad knowledge about linear colliders, has a unique contribution to make.  This view is shared by our government partner, the Department of Energy.

In November 2004 we will form the ILC collaboration at a workshop at KEK, which will bring together all the interested worldwide partners. The collaboration will initially proceed using the funding we have in place.  By the end of the year, we plan to identify a Director for the central design effort.  This Director will lead the Global Design Initiative, with regional coordinators from each geographical area.  After the design is finalized, the next step will be to have one or several governments come forward with an offer to host the facility.  If all goes well, the physics community could have a machine by 2015.

The Office of High Energy Physics in the DOE is backing our lab very strongly to move forward.  I anticipate the same financial level of support for the ILC effort at SLAC in 2005 as we had this year.  I am hopeful that, with this decision to consolidate the worldwide effort, we could see growth in funding that supports the ILC design in the years 2006 through 2009.  We currently have 100 full-time-equivalent staff working on the linear collider, representing roughly half of the worldwide effort.

For a while, it will not be completely business as usual. We do have to reorient the activities that have been specific to our warm technology to work on the new design. The linear collider test facility (NLCTA) here will play a different role as we move forward.  We need time to assess what will be closed out and what will be retained.   There are numerous opportunities and a lot of work to do.  SLAC is vigorously pursing a plan for our role in this exhilarating venture.

Let me encourage you all to embrace the ILC opportunity with enthusiasm so that SLAC can continue to be a leader in the worldwide community as it moves toward the construction of a machine that will reap tremendous physics benefits after it is completed. 

For the full text of the ICFA press release, see



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

Last update Thursday September 02, 2004 by Emily Ball