Accession Number:

ADA209653

Title:

Microwave Emission from Relativistic Electron Beams

Descriptive Note:

Final rept. 1 Nov 1983-31 Oct 1988

Corporate Author:

MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS

Personal Author(s):

Report Date:

1989-03-01

Pagination or Media Count:

40.0

Abstract:

Profile modification by optical guiding in a Raman free electron laser operating at microwave frequencies was studied experimentally. A cyclotron autoresonance maser CARM amplifier was designed, built, and tested. This CARM operates at 35 GHz with a power output of 10 MW and an efficiency of three percent. Observations of Field Profile Modifications in a Raman Free Electron Laser Amplifier We report measurements of the spatial distribution of the RF electric field intensities and phases induced in a free electron laser amplifier operating in the collective Raman regime. The studies are carried out at a microwave frequency of about 10 GHz in a FEL using a mildly relativistic electron beam of about 200 keV energy and 1 - 4 A current. The probing of the ponderomotive space charge and the electromagnetic waves is accomplished by means of small movable electric dipole antennas inserted into the interaction region. A 35 GHz Cyclotron Autoresonance Maser Amplifier Studies of a cyclotron autoresonance maser are presented. The measurements are carried out at a frequency of 35 GHz using a mildly relativistic electron beam 1.5 MeV, 260 A generated by a field emission electron gun followed by an emittance selector that removes the outer, hot electrons. Perpendicular energy is imparted to the electrons by means of a bifilar helical wiggler. Measurements give a small signal gain of 90 dBm and a saturated power output of 10 MW. The corresponding electronic efficiency is 3. Computer simulations are also presented.

Subject Categories:

  • Lasers and Masers

Distribution Statement:

APPROVED FOR PUBLIC RELEASE