A proposed experiment for beam conditioning

An experiment on beam conditioning (1) is proposed for the Accelerator Test Facility (ATF) at Brookhaven National Laboratory. The proposed demonstration will employ the already approved Harmonic Generation FEL (2) experiment (HGFEL) at the facility. The HGFEL experiment will use a 30 MeV electron beam from the ATF and a seed laser to produce a 3.4 micron radiation from a superconducting wiggler with a 1.8 cm period. In the proposed experiment, the beam energy is reduced to 17 MeV, and only the second wiggler of the HGFEL is employed. Resonance is made at 10.6 microns. The demonstration involves spoiling the emittance to drastically reduce the output power. A beam conditioning section introduces momentum variations correlated with betatron amplitude. This correlation will correct the deleterious effects of the artificially introduced emittance increase thus providing a clear demonstration of the conditioner