Status of the BNL IFEL accelerator

A 40 MeV electron beam, using the inverse free-electron laser interaction, has been accelerated by {Delta}E/E = 2.5% over a distance of 0.47 m. The electrons interact with a 1--2 GW CO{sub 2} laser beam bounded by a 2.8 mm ID sapphire circular waveguide in the presence of a tapered wiggler with Bmax {approx} 1 T and a period 2.89 cm {le} {lambda}{sub w} {le} 3.14 cm. The experimental results of {Delta}E/E as a function of electron energy E, peak magnetic field Bw and laser power W{sub 1} compare well with analytical and 1-D numerical simulations and permit scaling to higher laser power and electron energy. The present status of the IFEL accelerator and planned near term development are indicated