|MM-FEL||5.93 m||1.9 cm||12.7 cm||2.97 m||3.60 m|
|FIR-FEL||5.36 m||1.05 cm||7.6 cm||3.0 m||3.0 m|
|30µm-FEL||5.27 m||5.0 mm||5.5 cm||2.74 m||2.68 m|
These offer unique advantages for FELs that operate at long wavelength:
The FIR-FEL decay time, measured with a Schottky detector and fast digitizer, is fitted to an exponential to measure loss.
The table shows estimated contributions to this loss, where rc is coupling coefficient, lc is coupling loss (backscattering to higher order modes), lwg is resistive waveguide wall loss, ld is mirror edge diffraction loss, lm is mirror reflection loss, and lt is total loss.