Electron beam probe: The analysis of the electron beam spot expansion and a prototype development at IMP

Non-interceptive diagnostic techniques are essential for high beam power accelerators. An Electron Beam Probe (EBP) is preferable to measure the beam distribution of a dense beam bunch in which a low-intensity and low-energy electron beam sweeps across the ion beam and the deflection angle exerted on each electron by the space charge field of ion beam reflecting the local density distribution of the ion beam. In this paper, the design and setup of an EBP system, together with preliminary beam experiment result, are presented. A dedicated multi-particle simulation algorithm is developed which reproduces the expansion effect of electron beam spot in a dense ion bunch as observed by several Labs, and a theoretical interpretation is given with a preliminary solution being proposed. In the future, an improved version of EBP will supply non-interceptive diagnostics for Booster Ring (BRing) of the High Intensity heavy ion Accelerator Facility (HIAF), of which a fast scanning system will be implemented with the parallel electron beam optics configured.