1. Update on MEIC Nonlinear Dynamics Work
V.S. Morozov
Teleconference on Nonlinear Dynamics
June 2, 2015
F. Lin

2. Complete Ring Lattice
Two identical CCBs integrated: one upstream and one downstream
Original (without CCBs) natural x/y chromaticities: -101 / -112
Resulting (with CCBs) natural x/y chromaticities: -121 / -120
The strongest quad in the CCB is ~50% stronger than a regular FODO quad
Resulting x/y betatron tunes: / (can be adjusted) IP

3. Chromaticity Compensation
W functions minimized at the IP and around the ring by tuning
the phase advance between the CCBs and the IP (using thin trombones)
the sextupole strengths in the CCBs
4 families (two –I pairs and two individual sextupoles) with k2l = -0.10, 0.23, 0.19, -0.37
residual linear x/y chromaticities: / -29.1
Residual chromaticities compensated using 2 additional sextupole families
24 sextupoles per family (12 sextupoles of each family in 12 adjacent FODO cells per arc)
90 phase advance between adjacent sextupoles of each family
resulting sextupole strengths k2l = 0.25, (in the arc with positive dispersion, polarities reversed in the other arc)
final ring x/y chromaticities adjusted to +1 / +1
no effect on the W functions outside of the 12 FODO cell blocks
before compensation
after W function adjustment
after residual chromaticity compensation

4. First Tracking Results
Using MAD-X PTC
No synchrotron motion
x = 23.4 m, y = 4.7 m, p/p = 310-4
p/p = 0
p/p = 3p/p

5. Conclusions & Outlook
DA with y = 0 looks good, DA with y ≠ 0 is small, may be close to a resonance
Further work
Track with synchrotron oscillations
Benchmark Elegant
Systematic tracking studies: tune scan, tune footprint, etc.