The longitudinal energy spread of ion beams extracted from an electron cyclotron resonance ion source

We present a study of factors affecting the energy spread ion beams extracted from Charge Breeder Electron Cyclotron Resonance Ion Source (CB-ECRIS). The comprehensive simulations, supported by experiments with Retarding Field Analyser (RFA), reveal that longitudinal and transverse are strongly affected electrostatic focusing effects, namely extraction geometry plasma beam boundary, to extent effects dominate over magnetic field induced rotation or effect potential temperature. dominance complicates parametric studies emittance as function strength, comparison values obtained different sources having designs. Our results demonstrate full spread, relevant for downstream accelerator, can be measured RFA only when all ions collected. On contrary, studying properties (plasma temperature) on requires heavy collimation accepting near symmetry axis which suppressed. As system CB-ECRIS is similar conventional ECRIS, conclusions generalised apply high charge state ECR sources. Finally, we systematic measurements Phoenix-type at LPSC, varying source potential, microwave power axial srength. It was observed increases power.