Multiorder lasing with a modified wiggler
Abstract
A novel wiggler for multiorder harmonic lasing has been developed at ILT/ILE. This wiggler, called modified wiggler, produces a composite magnetic field that is expanded as a sum of harmonics of a fundamental field component: B(z) = B{sub 1} sin(k{sub 1}z) + B{sub 3} sin(3k{sub 1}z) + B{sub 5} sin(5k{sub 1}z) +{hor_ellipsis}, where k{sub 1} is the wavenumber of the fundamental field component and B{sub n} is the magnetic flux of nth order field component. Analytical work predicted the improvement of the gain on FEL harmonics with the modified wiggler. This effect on the gain is remarkable for the higher order harmonics, so that fifth or higher order harmonic lasing will be possible. We constructed a modified wiggler by arranging highpermeability shims inside the gap of a conventional wiggler of 20 mm period. This modified wiggler has a ratio of the thirdharmonic flux to the fundamental, B{sub 3}/B{sub 1}, of 10 %, which is enough to increase the gain on the FEL harmonics. The harmonic lasing experiment is now under way using a 9 MeV Sband photoinjector at ILT/ILE. Then the wavelength is 15 {mu}m at thirdharmonic and 10 {mu}m at fifthharmonic. The gain on the thirdharmonic is calculated tomore »
 Authors:

 Institute of Laser Technology, Osaka (Japan); and others
 Publication Date:
 Research Org.:
 Brookhaven National Lab. (BNL), Upton, NY (United States)
 OSTI Identifier:
 238786
 Report Number(s):
 BNL61982Absts.; CONF9508156Absts.
Journal ID: ISSN 01689002; ON: DE96002729; TRN: 96:013275
 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; WIGGLER MAGNETS; HARMONICS; FREE ELECTRON LASERS; MAGNETIC FIELDS; GAIN
Citation Formats
Asakawa, M, Fujita, M, and Chen, J. Multiorder lasing with a modified wiggler. United States: N. p., 1995.
Web. doi:10.1016/01689002(95)013830.
Asakawa, M, Fujita, M, & Chen, J. Multiorder lasing with a modified wiggler. United States. https://doi.org/10.1016/01689002(95)013830
Asakawa, M, Fujita, M, and Chen, J. 1995.
"Multiorder lasing with a modified wiggler". United States. https://doi.org/10.1016/01689002(95)013830. https://www.osti.gov/servlets/purl/238786.
@article{osti_238786,
title = {Multiorder lasing with a modified wiggler},
author = {Asakawa, M and Fujita, M and Chen, J},
abstractNote = {A novel wiggler for multiorder harmonic lasing has been developed at ILT/ILE. This wiggler, called modified wiggler, produces a composite magnetic field that is expanded as a sum of harmonics of a fundamental field component: B(z) = B{sub 1} sin(k{sub 1}z) + B{sub 3} sin(3k{sub 1}z) + B{sub 5} sin(5k{sub 1}z) +{hor_ellipsis}, where k{sub 1} is the wavenumber of the fundamental field component and B{sub n} is the magnetic flux of nth order field component. Analytical work predicted the improvement of the gain on FEL harmonics with the modified wiggler. This effect on the gain is remarkable for the higher order harmonics, so that fifth or higher order harmonic lasing will be possible. We constructed a modified wiggler by arranging highpermeability shims inside the gap of a conventional wiggler of 20 mm period. This modified wiggler has a ratio of the thirdharmonic flux to the fundamental, B{sub 3}/B{sub 1}, of 10 %, which is enough to increase the gain on the FEL harmonics. The harmonic lasing experiment is now under way using a 9 MeV Sband photoinjector at ILT/ILE. Then the wavelength is 15 {mu}m at thirdharmonic and 10 {mu}m at fifthharmonic. The gain on the thirdharmonic is calculated to be 27%, which is 1.5 times greater than that of nonmodified wiggler. The fifthharmonic lasing is seeded by a CO{sub 2} laser. We will discuss about the gain enhancement as a function of modification ratio.},
doi = {10.1016/01689002(95)013830},
url = {https://www.osti.gov/biblio/238786},
journal = {},
issn = {01689002},
number = 13,
volume = 375,
place = {United States},
year = {1995},
month = {12}
}