Demonstration of a high-power FEL oscillator with high extraction-efficiency

R. Hajima, N. Nishimori, R. Nagai, M. Sawamura, N. Kikuzawa, T. Shizuma, E. J. Minehara

Research output: Contribution to conferencePaperpeer-review

2 Citations (Scopus)


IR-FEL lasing over kilowatt average power has been demonstrated at JAERI-FEL driven by a superconducting linac. The lasing is distinguished from other FEL oscillators by its high extraction-efficiency, 6%, and unique cavity-length detuning curve. The lasing at JAERI-FEL has the maximum power at the perfect synchronism between the optical pulse and the electron bunch, while usual FEL oscillators require cavity-length shortening to compensate laser lethargy. Numerical analyses show that the lasing observed at JAERI-FEL is a new type of FEL lasing: quasi-stationary superradiance, which gives extraction efficiency higher than the theoretical prediction previously reported. Our analyses also indicate that long stable macro-pulses generated by superconducting linac are indispensable to establish this new type of lasing.

Original languageEnglish
Number of pages3
Publication statusPublished - 2001
Externally publishedYes
Event2001 Particle Accelerator Conference - Chicago, IL, United States
Duration: 2001 Jun 182001 Jun 22


Other2001 Particle Accelerator Conference
Country/TerritoryUnited States
CityChicago, IL

ASJC Scopus subject areas

  • Engineering(all)


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