Gabor or plasma lenses have previously been used to focus intense beams of positive ions at energies from 10 keV to 5 MeV. Such lenses are a possible candidate for matching an intense lowhyphen;energy proton beam into a radio frequency quadrupole accelerator (RFQ). The conventional solution has been to match an intense beam with two solenoid lenses. This leads to a timehyphen;dependent emittance at the RFQ entrance due to neutralization effects. The neutralization time of a spacehyphen;charge dominated 30ndash;50 mA proton beam in the Gabor lens is 1 mgr;s. A nonhyphen;neutral electron plasma is contained in the Gabor lens by a 200 G solenoid magnet. The equivalent thin lens focal length of a Gabor lens operated at Fermilab has been determined to be 10 cm. This focusing strength is adequate for matching a proton beam into an RFQ.
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