LET: Meetings: Minutes for 2005 May 24

Attending: Representatives from LEPP, FNAL, LBL, and SLAC

Peter Tenenbaum of SLAC gave a talk on his plan for LET studies in support of the ILC baseline design and the Conceptual Design Report. His talk is available here, with supplemental materials here and here. Much discussion, most notably there are concerns that the plan has too much work in it to be completed in time, and that the tasks have to be prioritized. In particular there was concern that the ultra-complete studies will not be finished in time for the CDR. The plan is also somewhat confusing in that the LET work includes optics design of several regions, and simulation studies of the BDS, but not actual design work on the BDS (which is handled in the BDS taskforce). The issue of task prioritization is strongly coupled to the answer to the question, "What do we need for the CDR, anyway?" It is hoped that we will have further fruitful discussions of these issues in the weeks leading up to Snowmass; participants are encouraged to use the LET forum at linearcollider.org for this purpose!

Reports from the Laboratories:

FNAL: Kirti Ranjan continuing his study of DFS performance as a function of quad spacing in the lattice; there are some fussy issues in the way that the first DFS region is handled that he is working with PT to resolve. Results soon.
LBL: Based on the results of the 1/2/3 stage BC study, Andy Wolski has assembled a second generation design of a 2-stage BC which has good versatility in terms of configurations and which makes more optimal use of installed RF voltages. This will be ready to hand off to PT for transverse emittance studies in a day or two.
SLAC: PT will run Andy's new BC through emittance studies later this week.

Old Business: At PAC, PT asked H. Padamsee about the effectiveness of magnetic shielding for the SC RF cavities (this came up during the May 10 meeting). Dr. Padamsee replied that the cavities built and tested at DESY had measured remnant fields at the level of 1-2 microTesla, which suggests that the shielding cancels the Earth's field to the level of 95-98%.

New Business: No items of new business.

Next Meeting: Tuesday, 07 June 2005, 12:30 / 11:30 / 9:30.