Efficiency enhancement experimentwith a tapered undulator in a single-pass seeded fel at the NSLS SDL

Author

Watanabe, T. ; Wang, X. ; Li, R. ; Shen, Y. ; Harder, D. ; Rakowsky, G. ; Murphy, J.B. ; Freund, H.P.

Author_Institution

BNL, Upton

fYear

2007

fDate

25-29 June 2007

Firstpage

1371

Lastpage

1373

Abstract

The experimental observation of FEL efficiency enhancement using a tapered undulator in a single-pass seeded FEL at the NSLS SDL is reported. The last 2.5 m of the 10 m NISUS undulator was linearly tapered so that the magnetic field strength at the end of the undulator was reduced by 5%. The FEL energy gain along the undulator was measured for both the tapered and un-tapered undulators. We observed that the FEL efficiency was more than doubled by applying the taper. The experimental results are compared with the numerical simulation code,GENE- SIS1.3 [1].

Keywords

electron beams; free electron lasers; magnetic fields; particle beam bunching; wigglers; FEL energy gain; NSLS SDL; electron beam energy; electron bunch duration; magnetic field strength; multi ring structure; single-pass seeded FEL efficiency enhancement; tapered undulator; Brightness; Electron beams; Electron traps; Energy measurement; Free electron lasers; Light sources; Magnetic field measurement; Magnetic fields; Magnetic resonance; Undulators;

fLanguage

English

Publisher

ieee

Conference_Titel

Particle Accelerator Conference, 2007. PAC. IEEE

Conference_Location

Albuquerque, NM

Print_ISBN

978-1-4244-0916-7

Type

conf

DOI

10.1109/PAC.2007.4441086

Filename

4441086