Beam Developments at TRIUMF

The cyclotron is routinely operated with three simultaneously extracted beams and more are planned. A double beam has been sent down one line with sufficient separation for magnetic splitting. The extracted beam intensity can now be continuously varied from 10³ to 10¹⁵ protons/s (170 μA). The highest intensities were obtained by the addition of a second harmonic buncher in the injection beam line. Direct measurements of the electromagnetic H^- stripping losses agree with those expected. Beam-defining slits have been used to reduce the energy spread (ΔE/E) of the extracted beam to 10^-3 at all energies between 200 and 500 MeV. Under certain circumstances the medium resolution spectrometer has measured a resolution a factor of two better. Depolarizing resonances have been located and one of them corrected. A number of new experimental facilities have been commissioned recently. These include a low intensity polarized proton line operating to a polarized target, a high luminosity, low energy π-μ channel, and a clean cloud or surface muon channel using a velocity separator. The influence of the beam size and target shape on the characteristics of secondary particles has been examined.