FEL gain measurement with a Novel Method

Masaki Fujimoto, Ryukou Kato, Keigo Kawase, Akinori Irizawa, Fumiyoshi Kamitsukasa, Hiroki Ohsumi, Masaki Yaguchi, Goro Isoyama, Shigeru Kashiwagi, Shigeru Yamamoto

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

A novel method to measure temporal development of the FEL power has been developed using a silicon bolometer, which response linearly to input over a wide range[1]. The Si bolometer has the time resolution of ∼1 ms, which is much longer than the FEL macropulse of a few μs, so that it measures energy in the macropulse. The number of amplifications is changed by varying the pulse length of electrons from the gun of the linac and energy in the FEL macropulse is measured at a wavelength ∼100 μm with the detector and appropriate Teflon absorbers. The energy development of the FEL macropulse is measured over eight orders of magnitude from a very low power level close to the incoherent radiation up to the FEL power saturation. The temporal development of the FEL power is derived from the energy development as a function of the number of amplifications. Then the FEL gain is derived from the power development. We measured energy development in the macropulse and derived the FEL gain at some cavity lengths. The maximum FEL gain thus evaluated is about 56 percent, which agrees with calculation by the Super-Mode theory.

Original languageEnglish
Title of host publicationFEL 2012 - 34th International Free Electron Laser Conference
Pages515-518
Number of pages4
Publication statusPublished - 2012
Event34th International Free Electron Laser Conference, FEL 2012 - Nara, Japan
Duration: 2012 Aug 262012 Aug 31

Publication series

NameFEL 2012 - 34th International Free Electron Laser Conference

Other

Other34th International Free Electron Laser Conference, FEL 2012
CountryJapan
CityNara
Period12/8/2612/8/31

ASJC Scopus subject areas

  • Nuclear and High Energy Physics

Fingerprint Dive into the research topics of 'FEL gain measurement with a Novel Method'. Together they form a unique fingerprint.

  • Cite this

    Fujimoto, M., Kato, R., Kawase, K., Irizawa, A., Kamitsukasa, F., Ohsumi, H., Yaguchi, M., Isoyama, G., Kashiwagi, S., & Yamamoto, S. (2012). FEL gain measurement with a Novel Method. In FEL 2012 - 34th International Free Electron Laser Conference (pp. 515-518). (FEL 2012 - 34th International Free Electron Laser Conference).