Progress in superconducting rf (srf) technology has led to dramatic changes in cryogenic losses, cavity gradients, and microphonic levels. Design principles for a compact high average power Energy Recovery FEL at IR wavelengths, consistent with the state of the art in srf, are outlined, High accelerating gradients, of order 20 MV/m at Q₀~1x10¹⁰ possible at rf frequencies of 1300 MHz and 1500 MHz, allow for a single-cryomodule linac, with minimum cryogenic losses. Filling every rf bucket, at these high frequencies, results in high average current at relatively low charge per bunch, thereby greatly ameliorating all single bunch phenomena, such as wakefields and coherent synchrotron radiation. These principles are applied to derive self-consistent sets of parameters for 100 kW and 1 MW average power IR FELs and are compared with low frequency solutions.

This work supported by U.S. DOE Contract No. DE-AC05-84ER40150, the Commonwealth of Virginia and the Laser Processing Consortium.

Authors: Lia Merminga and Stephen V. Benson

Submitted for FEL 2001, Darmstadt, FRG, August 20-24, 2001

Updated May 24, 2001

maintained by the Publications Manager