Wiggler terms may be generating unaccounted-for vertical amplitude-dependent tuneshift. Start with a wiggler-free lattice (chess_5289mev_lowemit_20100121.lat) and optimize using the now-standard routine developed on 2010.05.04.

Tune scans performed using the same initial amplitudes standard for 2GeV scans.

2fam sextupoles

optimized sextupoles

See update on 2010.08.31 for amplitude-dependent tuneshift plots.