Emittance Measurements for N+ and N2+ in an Ion Beam from a Cyclotron Ion Source

The radial density profiles and emittance have been measured for N+ and N2+ beams from a Penning-type ion source that has a hot filament. It was found that the emittance for an extraction voltage of 12 kV and for 50% of the beanw as 21 cm-mrad for N+ and about 12 cm-mrad for N2+ The difference between these two areas may, in part, be explained by a charge state dependence due to different velocities of the two ion beams.