Comparative study of nonideal beam effects in high gain harmonic generation and self-seeded free electron lasers

Agostino Marinelli, Claudio Pellegrini, Luca Giannessi, Sven Reiche

Research output: Contribution to journalArticle

21 Citations (Scopus)


In this paper we investigate and compare the properties of two narrow-bandwidth free-electron laser (FEL) schemes, one using self-seeding and the other high gain harmonic generation (HGHG). The two systems have been thoroughly studied analytically and numerically in the past. The aim of this work is to compare their performances when the FEL is driven by an electron beam with nonideal properties, thus including effects such as shot-to-shot energy fluctuations and nonlinear energy chirp. In both cases nonlinearities produce a bandwidth larger than the Fourier transform limited value. However, our analysis indicates that, for approximately the same output power levels, the self-seeding scheme is less affected than the HGHG scheme by quadratic energy chirps in the electron beam longitudinal phase space. This is confirmed by a specific numerical example corresponding to SPARX parameters where the electron beam was optimized to minimize the FEL gain length. The work has been carried out with the aid of the time dependent FEL codes GENESIS 1.3 (3D) and PERSEO (1D). © 2010 The American Physical Society.
Original languageEnglish
Article number070701
Pages (from-to)-
JournalPhysical Review Special Topics - Accelerators and Beams
Issue number7
Publication statusPublished - 7 Jul 2010
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • Physics and Astronomy (miscellaneous)
  • Surfaces and Interfaces

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