A low-neutron background slow-positron source

The addition of a thermionic RF gun and a photocathode RF gun will allow th e advanced photon source (APS) linear accelerator (linac) to become a free- electron laser (FEL) driver, As the FEL project progresses, the existing hi gh-charge DC thermionic gun will no longer be critical to APS operation and could be used to generate high-energy or low-energy electrons to drive a s low-positron source. We investigated possibilities to create a useful low-e nergy source that could operate semi-independently and would have a low-neu tron background. (C) 1999 Elsevier Science B.V. All rights reserved.