TUP2WA02
ANL, Argonne, Illinois, USA
An X-ray FEL Oscillator (XFELO) is capable of producing fully coherent flux of ~1015 photons /s/ (meV bandwidth) over the hard X-ray spectral range 5 to 25 keV. This is higher by about three orders of magnitude than that from the self-amplified-spontaneous-emission (SASE) sources and about six orders magnitudes than the MBA sources. A CW, MHz rep rate, multi-GeV superconducting linac, such as planned at several laboratories is ideally suited for operating an XFELO. The XFELO pulses are also highly stable in contrast to the SASE pulses. In contrast to the ultrafast sciences probed by SASE, the XFELO is well-suited for sciences probing ultra fine spectral resolution. An XFELO can thus greatly extend the parameter space of the techniques established in third generation sources (IXS, XPCS, NRS) as well as opening up entirely new field, for example the nuclear physics of Mössbauer states and fundamental physics with X-ray spectral comb. The performance listed above is based on experimentally demonstrated level of X-ray power density on diamond reflectors and a fixed (4%) out-coupling efficiency. Further enhancement could be feasible if these constraints can be relaxed.
