Director's Corner

28 September 2006

Barry Barish

Machine Advisory Committee Reviews the GDE

The Machine Advisory Committee (MAC) reviewed the GDE for the second time last week at KEK in Japan from 20 to 22 September. The MAC, appointed by the International Linear Collider Steering Committee, is made up of an experienced international group of accelerator experts. The first review was held at Fermilab last spring and served to introduce the committee to the GDE. This time, the review looked more deeply into specific areas of our efforts. Today, I highlight some of the key observations and recommendations of the committee, based on what we were told during the closeout session for this review. The complete report should be issued within a few weeks.

Nobel Laureate Burt Richter, a prominent MAC member
In the closeout, the committee chair Ferdinand Willeke (DESY) summarised the main conclusions of this review. He said that overall the committee was pleased with our progress on the design since their first meeting and on our responsiveness to the first MAC report. However, he also expressed the committee's disappointment that during the Japan meeting they were shown only limited information on our costing efforts, due to our confidentiality rules. Even though it meant that we could not get the committee's expert opinion on costing we believe it is essential that we protect confidential cost information. Before sharing our costs, we need to validate our costing internally and draw our own conclusions, then in addition, we must protect some proprietary information we have received.


The MAC also discussed design issues and endorsed the change of the baseline to 14mrad x 14mrad crossing angles, which I reported on in last week's column. They also expressed satisfaction with the efforts we have made to communicate design issues with the high-energy physics community, the initiation of a task force to demonstrate our baseline gradient of 31.5 MV/m, the studies and design considerations we are taking regarding availability and the progress we are making in coordinating the global R&D program.

GDE members Barry Barish and Nick Walker sharing a joke during the MAC review
On the other hand, the committee did not agree with our design philosophy of carrying a large parameter space (e.g. doing a design over a range of values for the key parameters) and suggested we concentrate on one parameter set. They also expressed concern over our lack of authority over the international R&D effort. And finally, they recommended that we give higher priority to machine protection systems. We will take all of these comments and the others in the report very seriously, as we move forward with the design.


The next meeting of the MAC will be at the Cockcroft Institute at Daresbury in the U.K. in January 2007. That review will be at a critical time for us as we should be very close to releasing our draft RDR with preliminary costing. That MAC review will provide an important check on our readiness.

2nd MAC Review slides

--by Barry Barish