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

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: 25.598 / 23.733 (can be adjusted) IP

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: -28.5 / -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, -0.49 (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

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

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.