Electron orbits in the microwave inverse FEL accelerator (MIFELA)
Abstract
The MIFELA is a new device based on stimulated absorption of microwaves by electrons moving along an undulator. An intense microwave field is used (a{sub s} = eE{sub s}/k{sub s} m c{sup 2} = 0.2) as well as a large undulator field (a{sub w}/{gamma} = eB{sub {perpendicular}}/{gamma}k{sub w} mc{sup 2} = 1/2) to accelerate electrons emitted at 6MeV from a rf gun to 20MeV in 1.5m. The spiral radius of the electrons in the undulator is 8mm, in a waveguide of diameter 34mm, with undulator period about 10cm. There is a small guiding field, and the electrons move in type I orbits. We describe three problems connected with the orbital motion of the electrons in this structure: (i) injecting the electrons in an increasing undulator field prior to entering the MIFELA; (ii) orbital motion and stability inside the MIFELA; (iii) extraction of electrons from the spiral orbit in the accelerator into an axiallypropagating beam, obtaining {Beta}{sub {perpendicular}} < 0.02. These studies have application to a MIFELA which is under construction at Yale University by OmegaP.
 Authors:
 Columbia Univ., New York, NY (United States)
 Publication Date:
 Research Org.:
 Brookhaven National Lab., Upton, NY (United States)
 OSTI Identifier:
 238664
 Report Number(s):
 BNL61982Absts.; CONF9508156Absts.
Journal ID: ISSN 01689002; ON: DE96002729; TRN: 96:013153
 Resource Type:
 Conference
 Resource Relation:
 Journal Volume: 375; Journal Issue: 13; Conference: 17. international free electron laser conference, New York, NY (United States), 2125 Aug 1995; Other Information: PBD: [1995]; Related Information: Is Part Of 17th international free electron laser conference and 2nd international FEL users` workshop. Program and abstracts; PB: 300 p.
 Country of Publication:
 United States
 Language:
 English
 Subject:
 43 PARTICLE ACCELERATORS; 42 ENGINEERING NOT INCLUDED IN OTHER CATEGORIES; FREE ELECTRON LASERS; BEAM DYNAMICS; WIGGLER MAGNETS; ELECTRON BEAMS; ORBITS; ACCELERATORS
Citation Formats
Zhang, T.B., and Marshall, T.C. Electron orbits in the microwave inverse FEL accelerator (MIFELA). United States: N. p., 1995.
Web. doi:10.1016/01689002(95)013539.
Zhang, T.B., & Marshall, T.C. Electron orbits in the microwave inverse FEL accelerator (MIFELA). United States. doi:10.1016/01689002(95)013539.
Zhang, T.B., and Marshall, T.C. 1995.
"Electron orbits in the microwave inverse FEL accelerator (MIFELA)". United States.
doi:10.1016/01689002(95)013539. https://www.osti.gov/servlets/purl/238664.
@article{osti_238664,
title = {Electron orbits in the microwave inverse FEL accelerator (MIFELA)},
author = {Zhang, T.B. and Marshall, T.C.},
abstractNote = {The MIFELA is a new device based on stimulated absorption of microwaves by electrons moving along an undulator. An intense microwave field is used (a{sub s} = eE{sub s}/k{sub s} m c{sup 2} = 0.2) as well as a large undulator field (a{sub w}/{gamma} = eB{sub {perpendicular}}/{gamma}k{sub w} mc{sup 2} = 1/2) to accelerate electrons emitted at 6MeV from a rf gun to 20MeV in 1.5m. The spiral radius of the electrons in the undulator is 8mm, in a waveguide of diameter 34mm, with undulator period about 10cm. There is a small guiding field, and the electrons move in type I orbits. We describe three problems connected with the orbital motion of the electrons in this structure: (i) injecting the electrons in an increasing undulator field prior to entering the MIFELA; (ii) orbital motion and stability inside the MIFELA; (iii) extraction of electrons from the spiral orbit in the accelerator into an axiallypropagating beam, obtaining {Beta}{sub {perpendicular}} < 0.02. These studies have application to a MIFELA which is under construction at Yale University by OmegaP.},
doi = {10.1016/01689002(95)013539},
journal = {},
number = 13,
volume = 375,
place = {United States},
year = 1995,
month =
}

By {open_quotes}inverting{close_quotes} the stimulated Cerenkov effect to stimulated Cerenkov absorption, it is possible to build an electron accelerator device driven by high power microwaves that propagate in a slowwave TM mode (axial Efield). An experiment now running at Brookhaven uses a powerful C02 laser and a 50MeV electron beam moving in a gasloaded cell. Our approach is to use the 15MW available at 2.865GHz from a SLAC klystron to accelerate an electron beam provided from an rf gun ({approximately}6MeV, few psec pulses) to energy {approximately}20MeV. The use of microwaves permits a well defined group of electrons to be accelerated inmore »

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