Date May 31, 2000
Attendees S. Danilov, B. Davis, J. Galambos, J. Holmes, D. Jeon,  D. Raparia
 
J. Galambos introduced the new summer student Brian Davis. 

D. Raparia presented some calculations on the impact of going to different operational energy.
The biggest impact is on the location of the energy corrector. For low energies 
(~ 800 KeV) the phase slip is large, and the corrector 
must be located near the end of the linac, and for high 
energies (say 1.3 GeV) the small phase slip requires locating the corrector farther from
the linac (other side of the achromat). Also every 50 MeV change in energy requires 
modification of the injection dipole to assure that the excited state lies 
between the n=4 and 5 states.Operating at lower energy also implies a reduced intensity 
that can be stored in the ring for a constant tune shift, implying a 1 MW beam for 800 MeV
and a 4 MW beam at 1.3 GeV, for the reference tune shift. Deepak also noted that the
beam profiles at the dumps had been given to the target group for analysis.

Slava Danilov has given Mafia analysis of the extraction kicker to S. Kurenoy for 
verification and is working with Jeff ofn the longitudinal impedance impact on the
beam. The effect of numerical accuracy and convergence is important, and 
needs to be analyzed.

Jeff Holmes finished his EPAC papaer, and also reported on the IU CIS experiments
performend last week at Indiana. He reported similar as Jie Wei that the beam appeared
to be scraping the septum at extraction, which clouded the space charge effects being 
sought. PDiscussions after the experiment was over indicate that it may be possible to 
remove the Lambertson septum and install an in situ harp in the ring to alleviate this 
problem, at a modest cost. This would be possible at the end of the summer.

John Galambos reported on the experience with the new MAD C++ version. The code is completely 
re-written. He put together an input file for SNS, which seemed to work. The new 
structure looks promising. Private communication with J. Jowett indicates that a space 
charge routine has also been written for  the new code.

D. Jeon is creating an input file for the beam breakup code for HOM work. He explained
briefly what this code does. It takes input from Mafia analysis on HOM modes, and tracks
a central particle throught the cavities.