Observation of superradiance in a short-pulse fel oscillator

Jaroszynski, D.A. and Chaix, P. and Piovella, N. and Oepts, D. and Knippels, G.M.H. and vanderMeer, A.F.G. and Weits, H.H. (1997) Observation of superradiance in a short-pulse fel oscillator. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 393 (1). pp. 332-338. ISSN 0168-9002 (http://dx.doi.org/10.1016/S0168-9002(97)80373-7)

Full text not available in this repository.Request a copy

Abstract

Superradiance has been experimentally studied, in a short-pulse free-electron laser (FEL) oscillator. Superradiance is the optimal way of extracting optical radiation from an FEL and can be characterised by the following scale laws: peak optical power P, scales as the square of electron charge, Q, (P, &unknown; Q2); the optical pulse duration, z, scales as the inverse of the square root of the charge, (z &unknown; 1/Q); the efficiency, , scales as the inverse of optical pulse length ( &unknown; 1/z &unknown; Q), which also implies that the relative spectral brightness defined by /(/) remains constant and close to 0.86. To characterise the properties of the superradiant emission, we have measured the efficiency, optical pulse energy, pulse duration and spectral width as functions of electron beam current and cavity loss for the optimum cavity length detuning. The efficiency has been deduced from measurements of electron beam energy spectra. The optical pulse duration has been determined from second-order autocorrelation measurements and the optical spectra determined using a grating spectrometer. We show that the superradiance in the oscillator has properties similar to that in a high-gain amplifier and discuss the links with spikes created by synchrotron instabilities.

  • Item type:Article
    ID code:18341
    Dates:
    Date
    Event
    1 July 1997
    Published
    Subjects:Science > Physics
    Department:Faculty of Science > Physics
    Depositing user: Strathprints Administrator
    Date deposited:31 Mar 2010 10:19
    Last modified:08 Apr 2024 17:23
    URI:https://strathprints.strath.ac.uk/id/eprint/18341
CORE (COnnecting REpositories)