Accelerator Physics Meeting 12/22/00

Present: J. Wei, M. Weishi Wan, Slava Danilov, Sasha Aleksandrov
D.O Jeon, Sarah Cousineau, J. Galambos,Paul Chu, Eugene Tanke,

J. Wei discussed the ongoing tune working point work. The promary
options are (6.3, 5.8) and (6.3, 5.3). The tune spread due to
space charge and chromaticity is being examined. It appears that
the two spreads do not combine linearly. Cases from an injection 
scenario designed to bump slowly (good target profile) showed a tune
spread of ~ 0.3 which is problemeatic w.r.t. the operating space.
When the bump is faster, the tune spread is closer to 0.2, with
chromaticity adding ~ 0.05 spread to the bottom part. Galambos will 
provide input on the impact of the corrector and spreader on the 

Slava Danilov noted that if the kickers are not coated to reduce 
secondary electron emission, that is a serious problem for SNS.
Sahas and Slava will estimate the conductivity of the ferrite
coating scenario,  using a conventional Ti-O technique.

The best way to scale the e-p inmstability threshold was discussed.
M. Blaskiewicz has a model which scales with the transvers tune depression. 
This was questioned since the instability is observed to start at the
bunch tail where the space charge is minimum.

Ingo Hoffman will have a workshop on space charge May 15th.

Sasha noted that the LBNL ion source still is producing low current

J. Galambos and P. Chu reported on a visit to BNL to discuss
using Cdev for server-client needs in the application programing.