Date Sept. 14, 2000
Attendees S. Aleksandrov, N. Catalan, Sarah Cousineau, S. Danilov, M. Doleans, 
J. Galambos, SJ. Holmes, . Kim, N. Malitsky, S. Martin, 
I. Papaphilloupou, W. Wan, J. Wei
 
Sig Martin will be staying at the SNS Project office for the next several months.
He is from the ESS project.

J. Wei discussed the results from the ASAC meeting (see below). Some points
directing related to our group are the need for more in depth linac
physics analysis, and the need for better interface between the physics
group and the diagnostics. The entire group needs  to help formulate the
requirements for the measurements / application programs. This is the starting 
point for the input to the diagnostics group.

Nickolay Malitsky poresented a status report on UAL. He is working with 
Andre Shilov, porting UAL to linux, and providing documentation of the PERL
inteface. This is for the UAL-1 version, used primarily for simulation.
UAL2 will be another version osed for online programing. At the JLab
EPICS database  meeting, the optics and magnet database work was reported 
and well recieved as this work is needed elsewhere.

Jie. Wei brought up a problem interfacfing accelerator elements in drawings. 
There are mistakes in the drawings, connecting parts together. We need to define 
global coordinates at the interfaces between major components. J. Galambos and 
W. Wan will  work on this.

J. Holmes discussed PSR space charge work. He reviewed the work done over the 
last year. More recently he applied a particle core model and obseved a core 
oscillation at twice the coherent tune. He also developed an analytical 
Hamiltonian treatment of the core showing a bifurcation of the solution at
high enough intensities.



ASAC Findings:
--------------

(1) (all) More, detailed linac physics work is needed
(2) (all) One needs to seriously consider adjustable quad for DTL. There is
     about 90 m section without tuning, and this is a significant portion
(3) (D. Bousard) linac RF overhead marginal. At the present level, one
     should not assume that we can retune to the same energy with missing
     cavity.
(4) (D. Proch) Stronger interface on linac is needed. There are two examples
     (a) lack of communication between cavity design and PS
     (b) lack of integrated HOM study
(5) (M. Harrison) Strong interaction between AP and diagnostics group is a
     must, merely passing parameters is not enough. One really needs to
     understand what we are measuring, how to measure, and what are the
     algorithms.
(6) (P. Schemmor) Front End simulation should assume the presently measured
     (undesired) characteristics, instead of ideal distribution, for
     simulation. Thus one can evaluate worst-case impact.
(7) (G. Rees) Ring related issues
     (a) Extraction reliability is highly important. It is hard to imagine that
         there can actually be no loss in the case of one kicker failure.
         One should consider having hot spare kicker.
     (b) The injection timing should be adjustable so that during short-pulse
         commissioning/operation, one can extract the beam as soon as the
         injection ends (instead of wait and then extract).
     (c) Collimators are needed! One needs to carefully check trip rate and
         allowed activation level to ensure smooth commissioning.
     (d) One should consider using 200 kW dump during linac commissioning to
         simplify problem.
     (e) Sextupoles are very useful (Some suggest: how can you live
         without it?). However, the balance with budget and the final decision
         should be the project office's.
     (f) Bellow shielding: no suggestion as whether it is needed but ISIS
         shielded design shows no mechanical problem during operation.
(8) (M. Harrison) Commissioning can be very disruptive on constructions.
     One should strongly consider alternative commissioning plan as lumping
     the period for commissioning.
(9) Next suggested ASAC: Feb. 5, 2001, Berkeley.