Andonian G, Murokh A, Rosenzweig J B, Agustsson R, Babzien M, Ben-Zvi I, Frigola P, Huang J Y, Palumbo L, Pellegrini C, Reiche S, Travish G, Vicario C, Yakimenko V
Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095, USA.
Phys Rev Lett. 2005 Jul 29;95(5):054801. doi: 10.1103/PhysRevLett.95.054801. Epub 2005 Jul 25.
Observation of ultrawide bandwidth, up to 15% full-width, high-gain operation of a self-amplified spontaneous emission free-election laser (SASE FEL) is reported. This type of lasing is obtained with a strongly chirped beam (deltaE/E approximately 1.7%) emitted from the accelerator. Because of nonlinear pulse compression during transport, a short, high current bunch with strong mismatch errors is injected into the undulator, giving high FEL gain. Start-to-end simulations reproduce key features of the measurements and provide insight into mechanisms, such as angular spread in emitted photon and electron trajectory distributions, which yield novel features in the radiation spectrum.
报道了对一种自放大自发辐射自由电子激光(SASE FEL)的超宽带宽(高达15%全宽)、高增益运行的观测。这种激光是由加速器发射的强啁啾光束(ΔE/E约为1.7%)产生的。由于传输过程中的非线性脉冲压缩,一个具有强失配误差的短而高电流的束团被注入到波荡器中,从而实现了高自由电子激光增益。从头到尾的模拟再现了测量的关键特征,并深入了解了诸如发射光子的角分布和电子轨迹分布等机制,这些机制在辐射光谱中产生了新的特征。