Minutes SNS Accelerator Physics Group Mtg.
12/17/01
Present: J. Wei, J. Galambos, S. Henderson, S. Danilov, J. Holmes, 
S. Cousineau, E. Tanke, S. Aleksandrov, D. Jeon, S. Kim, M. Doleans, P. Chu, 
A.Shishlo, S. Assadi, J. Stovall

J. Wei noted that there was a concern on the dose rate of the linac 
reference line (refered to as the frequency mixer) and the cavity phase 
allowable error. These need to be documented.  D. Jeon noted that he had 
done an analysis assuming a systematic 0.1 deg. error between cavities, 
and the affect on the final beam delta E and delta-phi was minimal. 
A short note will be written.

A question arose to whether we need additional instrumentation cabling 
to the HOM couplers. Kim will talk to M. Champion on the HOM heat load 
expected likelyhood  tech note already is written).

The ring extraction kicker impedance was remeasured with fewer ferrite 
blocks and showed a dramatic decrease in the impedance. Reduced mu ferrite 
is being ordered to see if the trend holds.

S. Cousineau noted that the collimation section performance has been improved 
by rearranging the location of some collimators. Also the ORBIT anfd K2 
codes appear to be benchmarked.

J. Holmes reviewed the experiments done at the PSR. Varying intensities, 
beam sizes and painting schemes (hollow vs. full) were done, and a wealth 
of benchmarking data available.