The sensitivity of nonlinear harmonic generation to electron beam quality in free electron lasers

Sandra G. Biedron, Zhirong Huang, Kwang-Je Kim, Stephen Milton, Giuseppe Dattoli, Pier Luigi Ottaviani, Alberto Renieri, William M. Fawley, Henry P. Freund, Heinz-Dieter Nuhn

Research output: Contribution to journalArticle

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The generation of harmonics through a nonlinear mechanism driven by bunching at the fundamental has sparked interest as a path toward enhancing and extending the usefulness of an X-ray free-electron laser (FEL) facility. The sensitivity of the nonlinear harmonic generation to undulator imperfections, electron beam energy spread, peak current, and emittance is important in an evaluation of the process. Typically, linear instabilities in FELs are characterized by increased sensitivity to both electron beam and undulator quality with increasing harmonic number. However, since the nonlinear harmonic generation mechanism is driven by the growth of the fundamental, the sensitivity of the nonlinear harmonic mechanism is not expected to be significantly greater than that of the fundamental. In this paper, we study the effects of electron beam quality, more specifically, emittance, energy spread, and peak current, on the nonlinear harmonics in a 1.5-Å FEL, and show that the decline in the harmonic emission roughly follows that of the fundamental. © 2002 Elsevier Science B.V. All rights reserved.
Original languageEnglish
Pages (from-to)101 - 106
Number of pages6
JournalNuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Issue number1-2
Publication statusPublished - 1 May 2002
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • Instrumentation

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