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Title: Impact of zero order unconverted light on beam pointing

Abstract

There is a significant amount of unconverted light incident in the NIF target chamber. The baseline plan for managing this light is to use a sub-aperture CSG design. This CSG selection impacts the target chamber and near-opposing FOAs due to: (1) zero order unconverted light footprint, and (2) high order dispersed unconverted light. In this memo we describe the impact of the zero order light on the range of beam pointing for individual beams. We show that zero order footprint for 1w light enters into the near-opposite FOAs for several ports if the beams are pointed away from the target chamber center. Additionally, for the case where 3w is allowed to propagate past target chamber center, the converted light may enter into the near-opposite FOAs. The second aperture in the PAM is required to protect the FOAs and still accommodate offset beam pointing on NIF. We present details on the aperture requirements to accommodate a range of beam pointing.

Authors:
; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab., CA (US)
Sponsoring Org.:
USDOE Office of Defense Programs (DP) (US)
OSTI Identifier:
13900
Report Number(s):
UCRL-ID-135816; DP0210000
DP0210000; TRN: US0110836
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 24 Aug 1999
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; US NATIONAL IGNITION FACILITY; APERTURES; DESIGN; TARGET CHAMBERS; LASER RADIATION; BEAM POSITION

Citation Formats

Dixit, S, Kalantar, D, and Lyons, R. Impact of zero order unconverted light on beam pointing. United States: N. p., 1999. Web. doi:10.2172/13900.
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Dixit, S, Kalantar, D, & Lyons, R. Impact of zero order unconverted light on beam pointing. United States. doi:10.2172/13900.
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Dixit, S, Kalantar, D, and Lyons, R. Tue . "Impact of zero order unconverted light on beam pointing". United States. doi:10.2172/13900. https://www.osti.gov/servlets/purl/13900.
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@article{osti_13900,
title = {Impact of zero order unconverted light on beam pointing},
author = {Dixit, S and Kalantar, D and Lyons, R},
abstractNote = {There is a significant amount of unconverted light incident in the NIF target chamber. The baseline plan for managing this light is to use a sub-aperture CSG design. This CSG selection impacts the target chamber and near-opposing FOAs due to: (1) zero order unconverted light footprint, and (2) high order dispersed unconverted light. In this memo we describe the impact of the zero order light on the range of beam pointing for individual beams. We show that zero order footprint for 1w light enters into the near-opposite FOAs for several ports if the beams are pointed away from the target chamber center. Additionally, for the case where 3w is allowed to propagate past target chamber center, the converted light may enter into the near-opposite FOAs. The second aperture in the PAM is required to protect the FOAs and still accommodate offset beam pointing on NIF. We present details on the aperture requirements to accommodate a range of beam pointing.},
doi = {10.2172/13900},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Aug 24 00:00:00 EDT 1999},
month = {Tue Aug 24 00:00:00 EDT 1999}
}
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DOI:  10.2172/13900
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