Improved Beam Quality at TRIUMF

Improved stability, together with the use of beam-defining apertures, have enabled us to extract separated turns at 200 MeV. This implies an extracted energy spread of 0.25 MeV FWHM and a time width of 0.3 ns FWHM; 0.6 MeV and 0.6 ns, which includes instrumental resolution, have been measured. Mechanical stiffening of the RF resonators has recently reduced the dee voltage fluctuations to ±0.015% while the magnetic field fluctuations are ±2 × 10-6. The machine set-up procedure for separated turns will be described. The compensation of the residual magnetic first harmonic has also been improved and should eventually permit lower loss in high-current operation.