Abstract
The performance of a free-electron laser (FEL) depends significantly on the various parameters of the driving electron beam. In particular, a large energy spread in the beam results in a substantial reduction of the FEL gain, an effect which is especially relevant when one considers FELs driven by plasma accelerators or ultimate storage rings. For such cases, one possible solution is to use a transverse gradient undulator (TGU). In this concept, the energy spread problem is mitigated by properly dispersing the electron beam and introducing a linear, transverse field dependence in the undulator. This paper presents a self-consistent theoretical analysis of a TGU-based, high-gain FEL which takes into account three-dimensional (3D) effects, including beam size variations along the undulator. The results of our theory compare favorably with simulation and are used in fast optimization studies of various x-ray FEL configurations.
Highlights
In recent years, with the successful commissioning of several major facilities around the world [1,2,3,4], the freeelectron laser (FEL) has demonstrated its immense value as a tunable source of intense, coherent x rays
The latter are characterized by high energy (∼1 GeV), low normalized emittance (∼0.1 μm) and very high peak current, features which make them attractive for compact FEL applications. They have a relatively large energy spread (∼1%) compared to beams from conventional accelerators. Another potential scheme involves the use of the beam from an ultimate storage ring (USR) [6] in a high-gain FEL situated in a bypass close to the ring [7]
III, we present the results of a numerical study which explores two different concepts for a soft x ray, transverse gradient undulator (TGU) FEL, namely a compact device driven by an laser-plasma accelerators (LPAs) and a machine based on an ultimate storage ring
Summary
With the successful commissioning of several major facilities around the world [1,2,3,4], the freeelectron laser (FEL) has demonstrated its immense value as a tunable source of intense, coherent x rays. One prominent example is that of FELs driven by electron beams from laser-plasma accelerators (LPAs) [5] The latter are characterized by high energy (∼1 GeV), low normalized emittance (∼0.1 μm) and very high peak current (up to 10 kA), features which make them attractive for compact FEL applications. They have a relatively large energy spread (∼1%) compared to beams from conventional accelerators Another potential scheme involves the use of the beam from an ultimate storage ring (USR) [6] in a high-gain FEL situated in a bypass close to the ring [7].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
