| Paper | Title | Page |
|---|---|---|
| MOPPH056 | Generation of Attosecond X-ray Pulses with a Multi-Cycle Two-Color ESASE Scheme | 114 |
|
||
|
Generation of attosecond x-ray pulses is attracting much attention within the x-ray free-electron laser (FEL) user community. Several schemes have been proposed based on manipulations of electron bunches with extremely short laser pulses. In this paper, we extend the attosecond two-color ESASE scheme* to the long optical cycle regime using a detuned second laser** and a tapered undulator. Both lasers can be about ten-optical-cycle long, with the second laser frequency detuned from the first one in order to optimize the contrast between the central and side current spikes. A tapered undulator can be used to mitigate the degradation effect of the longitudinal space charge force in the undulator*** as well as to suppress the FEL gain of all side current spikes. Simulations using the LCLS parameters show a single attosecond x-ray spike of ~100 attosecond can be produced with a good contrast ratio.
* A. A. Zholents and G. Penn, Phys. Rev. ST Accel. Beams 8, 050704 (2005). |