Target Wheel Introduction

An aluminium wheel that carries thin targets is used in TASCA experiments to enhance the ion beam intensity by distributing the energy loss across a larger surface. The target frames are segmented for stability reasons. The ion beam must not hit the aluminium support. Therefore the rotation frequency and phase of the target wheel must be synchronized with the ion beam bunch frequency and phase. Since the RF accelerator cavity power supplies are driven directly from the public power distributor (HEAG) the frequency and phase can vary slowly within certain limits. Hence, the target wheel motor needs to be driven by a closed control loop in real time. The purpose of this project is to develop a replacement for the existing, but outdated and 20 years old, solution. The new solution should be based on state of the art industrial components. It should be easy to maintain and needs good documentation. The operation should be fool safe since the support structure could be activated or potentially radioactive targets could become destroyed with serious consequences. Therefore the system must be very reliable and connected with the accelerator interlock system.

-- HolgerBrand - 05 Oct 2009