Operating synchrotron light sources with a high gain free electron laser

S Di Mitri, M Cornacchia
2015 New Journal of Physics  
The peak current required by a high gain free electron laser (FEL) is not deemed to be compatible with the multi-bunch filling pattern of synchrotrons. We show that this problem can be overcome by virtue of magnetic bunch length compression in a ring section and that, after lasing, the beam returns to equilibrium conditions without beam quality disruption. As a consequence of bunch length compression, the peak current stimulates a high gain FEL emission, while the large energy spread makes the
more » ... eam less sensitive to the FEL heating and to the microwave instability. The beam large energy spread is matched to the FEL energy bandwidth through a transverse gradient undulator. Feasibility of lasing at 25 nm is shown for the Elettra synchrotron light source (SLS) at 1 GeV. Viable scenarios for the upgrade of existing or planned SLSs to the new hybrid insertion devices-plus-FEL operational mode are discussed, while ensuring little impact on the standard beamlines functionality [1].
doi:10.1088/1367-2630/17/11/113006 fatcat:j4nm3igk4vhvdfxjp4vreosh6u