KJK, Cornell, May 23, 2008 27 Performance of X-FELO Spectral range: 5 keV<   <20 keV Full transverse and temporal coherence in ~1 ps (rms) –  /  FWHM =2.5 10 -7 ; h  =2 meV (rms) Tunable 10 9 photons (~ 1  J) /pulse –Peak spectral brightness~LCLS Rep rate 1-100 MHz  average spectral brightness (10 26 -10 29 ) #/(mm-mr) 2 (0.1%BW) The average spectral brightness is higher by a factor of –10 5 -10 7 than other future light sources considered so far, ERL- based or high-gain FEL-based –Current APS about 100-1000 less than ERL
{}