The first Baseline Assessment Workshop for the ILC held at KEK

30 Sep 2010


7-10 September, the first baseline assessment workshops (BAW-1) took place at KEK with 63 scientists and engineers from around the world.

The Global Design Effort (GDE), an international team tasked with designing the International Linear Collider (ILC), has published the Reference Design Report (RDR) in 2007, which provides the essential features of the facility such as layout, parameters and components to serve as the basis for the final engineering design.

Over the past months the GDE has developed a process for assessing the major changes to the ILC baseline described in the RDR towards the Technical Design Report (TDR) to be completed by 2012. The motivation for the proposed changes is to evolve the ILC design to better optimize cost to performance to risk, with special emphasis on cost savings that will help insure that we keep control over the cost. BAW is the series of workshops to assess each proposed change, to provide the information and a recommendation that will enable an informed formal evaluation and decision.

Participants had intensive discussion on the 'Single-tunnel with improved high-level radiofrequency (RF) systems' for the first two days. One of the most important proposed changes is adopting the single-tunnel configuration, which involves the considerations on the high-level RF system, because the system in RDR was designed to be installed into the service tunnel along to the accelerator tunnel in the double-tunnel configuration.

The last two days of BAW-1 focused on the baseline choice for the accelerating gradient and the strategy towards future gradient improvements, which involves questions of material and fabrication, surface processes, instrumentation and repair; developing a strategy to overcome quenches, and field emission; and improving the gradient and production yield. The strategy for tuning and control, tolerances and availability margin, and the impact on other accelerator systems including conventional facilities, RF and cryogenics were also discussed.

Next meeting BAW-2 will be held at SLAC from 18-21 January 2011, focusing on proposed changes to the ILC Technical Design Baseline: 'Reduced Beam Parameter set' and 'Positron Source Location'.