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Title: Absorber for terahertz radiation management

Abstract

A method and apparatus for minimizing the degradation of power in a free electron laser (FEL) generating terahertz (THz) radiation. The method includes inserting an absorber ring in the FEL beam path for absorbing any irregular THz radiation and thus minimizes the degradation of downstream optics and the resulting degradation of the FEL output power. The absorber ring includes an upstream side, a downstream side, and a plurality of wedges spaced radially around the absorber ring. The wedges form a scallop-like feature on the innermost edges of the absorber ring that acts as an apodizer, stopping diffractive focusing of the THz radiation that is not intercepted by the absorber. Spacing between the scallop-like features and the shape of the features approximates the Bartlett apodization function. The absorber ring provides a smooth intensity distribution, rather than one that is peaked on-center, thereby eliminating minor distortion downstream of the absorber.

Inventors:
; ; ; ; ;
Publication Date:
Research Org.:
Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1230013
Patent Number(s):
9,209,587
Application Number:
14/662,322
Assignee:
JEFFERSON SCIENCE ASSOCIATES, LLC TJNAF
DOE Contract Number:
AC05-06OR23177
Resource Type:
Patent
Resource Relation:
Patent File Date: 2015 Mar 19
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; 61 RADIATION PROTECTION AND DOSIMETRY

Citation Formats

Biallas, George Herman, Apeldoorn, Cornelis, Williams, Gwyn P., Benson, Stephen V., Shinn, Michelle D., and Heckman, John D. Absorber for terahertz radiation management. United States: N. p., 2015. Web.
Biallas, George Herman, Apeldoorn, Cornelis, Williams, Gwyn P., Benson, Stephen V., Shinn, Michelle D., & Heckman, John D. Absorber for terahertz radiation management. United States.
Biallas, George Herman, Apeldoorn, Cornelis, Williams, Gwyn P., Benson, Stephen V., Shinn, Michelle D., and Heckman, John D. 2015. "Absorber for terahertz radiation management". United States. doi:. https://www.osti.gov/servlets/purl/1230013.
@article{osti_1230013,
title = {Absorber for terahertz radiation management},
author = {Biallas, George Herman and Apeldoorn, Cornelis and Williams, Gwyn P. and Benson, Stephen V. and Shinn, Michelle D. and Heckman, John D.},
abstractNote = {A method and apparatus for minimizing the degradation of power in a free electron laser (FEL) generating terahertz (THz) radiation. The method includes inserting an absorber ring in the FEL beam path for absorbing any irregular THz radiation and thus minimizes the degradation of downstream optics and the resulting degradation of the FEL output power. The absorber ring includes an upstream side, a downstream side, and a plurality of wedges spaced radially around the absorber ring. The wedges form a scallop-like feature on the innermost edges of the absorber ring that acts as an apodizer, stopping diffractive focusing of the THz radiation that is not intercepted by the absorber. Spacing between the scallop-like features and the shape of the features approximates the Bartlett apodization function. The absorber ring provides a smooth intensity distribution, rather than one that is peaked on-center, thereby eliminating minor distortion downstream of the absorber.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2015,
month =
}

Patent:

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