The Joint Accelerator Conferences Website (JACoW) is an international collaboration that publishes the proceedings of accelerator conferences held around the world.
TY - CONF AU - Zhou, G. AU - Jiao, Y. AU - Wu, J. AU - Xu, G. AU - Zhang, T. ED - Petit-Jean-Genaz, Christine ED - Kim, Dong Eon ED - Kim, Kyung Sook ED - Ko, In Soo ED - Schaa, Volker RW TI - Power Improvement of Free-Electron Laser Using Transverse-Gradient Undulator with External Focusing J2 - Proc. of IPAC2016, Busan, Korea, May 8-13, 2016 C1 - Busan, Korea T2 - International Particle Accelerator Conference T3 - 7 LA - english AB - Resent study [Z. Huang et al., Phys. Rev. Lett. 10⁹, 204801 (2012)] shows that the transverse-gradient undu-lator (TGU) together with electron beams with constant dispersion can reduce the sensitivity to energy spread for FEL. In this study, we numerically study FEL using TGU with external focusing. In spite of the dispersion varia-tion, through parameter optimization, FEL using TGU with TGU achieves similar radiation to that without ex-ternal focusing. To achieve a high energy exaction effi-ciency, the initial dispersion should be set with a shift from that corresponding to the resonant condition, and a variation of the transverse gradient in different undulator section is preferred. Other approaches, such as tapering and detuning frequency control, are also discussed to further improve the radiation power and are demonstrated with global parametric optimizations base on simulation. PB - JACoW CP - Geneva, Switzerland SP - 760 EP - 762 KW - FEL KW - focusing KW - radiation KW - undulator KW - electron DA - 2016/06 PY - 2016 SN - 978-3-95450-147-2 DO - 10.18429/JACoW-IPAC2016-MOPOW020 UR - http://jacow.org/ipac2016/papers/mopow020.pdf ER -