This photograph shows the view along the beamline axis of a meter-long plasma source designed to be placed in the path of an intense ion beam so that the ions can "grab" plasma electrons and become charge-neutral. A charge-neutral ion beam can be compressed to a small spot to heat a target. The plasma source is not on in this photograph and the natural illumination is from a hot ion source visible in the center. The interior of the three-inch-diameter plasma source is lined with perforated steel sheets held in place by thin wires and small screws that can be seen in the photograph.