The proton synchrotron Desy III

Desy III is one link in the chain of injectors for HERA, the electron/positron-proton colliding beam storage ring. Because of the relatively low injection (kinetic) energy of 50 MeV space charge plays a significant role in determining the achievable accelerated current. The luminosity in HERA is critically dependent on the transverse beam brightness hence the need to examine, and where possible minimise, emittance blow-up. Measurements of the beam emittance as a function of intensity in Desy III and the derived incoherent space charge tune shift are presented and discussed. Finally some preliminary investigations with regard to upgrading the injection energy via a pre-booster are described