Li-beam developments for high-energy plasma diagnostics

Detailed testing of the high-energy Li-beam at JET is described. A new method is presented for beam profile measurement. Details of beam profile, current are systematically measured for various extraction and acceleration voltages and emitter heating powers. Results show that the beam current is limited by the emission capacity of the ion emitter. First measurements of a new emitter capable of delivering 7 mA/cm2 are presented.