ILC NewsLine
Frascati Meeting Concludes with BCD Recommendations and New GDE Structure

Nick Walker kept the BCD session of the meeting under control with a "rotten paper tomato" on hand.
Following last week’s meeting in Frascati, the GDE members and other attendees returned this week with only a few minor bumps and bruises from an onslaught of "rotten tomatoes".

"I was afraid that each speaker would need a flak jacket to present each portion of the Baseline Configuration Document because this is the chance for everyone to say what they didn’t get to say before.", said SLAC’s Tom Himel, who opened the session, "Discussion and Approval of the BCD" at the Frascati meeting. "I thought that some people might want to bring rotten tomatoes to throw when they heard something they didn’t like. I didn’t think that bringing rotten tomatoes would be that convenient though, so instead I brought these red paper balls as an alternative."

Even though a few of the "rotten paper tomatoes" did indeed get tossed around in fun during the meeting, flak jackets as it turned out were not necessary. "The recommendations as outlined here today are not final.", said DESY’s Nick Walker who chaired the session. "If you have comments, the recommendations can be changed. Many questions and decisions still remain. There is going to be a lot of work over the next two months or so to make sure that we have the relevant details that we need."

Some of the major recommendations discussed at Frascati include the energy upgrade, number of tunnels, curvature of the tunnel and the number of interaction regions. Kaoru Yokoya, a member of the GDE Executive Committee, outlined the recommendations made in the BCD. "The BCD concluded that a 500 GeV tunnel would be built because of its lower first stage cost.", he said. As the current recommendation stands, a 20 km tunnel would be built during the first stage of the project. An upgrade would occur in between the first and second stage of the project, bringing the machine up to an energy of 1 TeV and increasing the length of the tunnel to approximately 40 km.

"The BCD agrees with the recommendations made at Snowmass to build two tunnels.", Yokoya said. "The additional cost will only be minimal, and maintenance will be much easier." The BCD also recommended two interaction regions and a tunnel that would follow the curvature of the earth, rather than be laser-straight. More details about the BCD are available online.

Over the course of the next few weeks, the BCD will be condensed and summarized into a 100 page electronic document and turned over to the Change Control Board (CCB). Chaired by Nobu Toge, the CCB will be responsible for completing the BCD before the next GDE meeting in March 2006. "The CCB has to take ownership of the document that we have now.", said GDE Director Barry Barish. "They will direct any information that is missing. Any changes will have to come from the CCB, and they will have to figure out how to make the changes. This board is meant to be a facilitator and to keep order in our system." Suggestions for the Change Control Board can be sent to

In addition to establishing the Change Control Board, Barish also created two other boards to carry out the tasks of the GDE. The Design Cost Board, chaired by Fermilab’s Peter Garbincius, will be responsible for assessing and providing guidance for the overall Reference Design Report (RDR). This board will propose an overall structure and content for the RDR, which will be developed by the end of 2006. The Global R&D Board, chaired by Columbia University’s Bill Willis, will suggest priorities for the research facilities, R&D supporting the BCD and R&D on alternatives to the BCD.

The next major milestone for the GDE will be the meeting in Bangalore, India on 9-11 March 2006. After Bangalore, the GDE will meet in Vancouver, Canada on 18-20 July 2006 and in parallel with ECFA on 6-8 November 2006 in Valencia, Spain.

"Keep up the momentum. It is tremendous.", said SLAC Director Jonathan Dorfan, providing words of inspiration during the Frascati meeting. "It is my strong belief that we will get to build and complete the ILC in the next decade, and I can’t wait to be there to see the first events."

All talks and images from the Frascati meeting are available online.

--Elizabeth Clements