Unabsorbed light beamlets for diagnosing cross-beam energy transfer

doi:10.1063/1.5036565

This content will become publicly available on July 9, 2019

Title: Unabsorbed light beamlets for diagnosing cross-beam energy transfer

Here, a new diagnostic has been fielded on OMEGA to diagnose cross-beam energy transfer (CBET) during direct-drive implosions. Unabsorbed light from each OMEGA laser beam is imaged as a distinct “spot” onto a gated optical imager. Each spot is in essence the end point of a beamlet of light that originates from different regions of each beam profile and follows a path determined by refraction. The intensity of light in the beamlet varies along its path as a result of absorption and CBET with other beamlets. This diagnostic allows the investigation of the effects of CBET on laser energy from specific locations of the beam profile. The diagnostic records images in two 200-ps time windows and includes a Wollaston prism to split each beamlet into two orthogonal polarizations recorded on separate images, allowing the absolute polarization of each beamlet to be determined. This diagnostic has provided the first evidence of polarization rotation caused by CBET during direct-drive implosions.

Authors:

Edgell, D. H. ^[1] ; Katz, J. ^[1] ; ;

Univ. of Rochester, Rochester, NY (United States). Lab. for Laser Energetics

Publication Date:: 2018-07-09

Report Number(s):: 2017-258, 2374
Journal ID: ISSN 0034-6748; 2017-258, 2374, 1416

Grant/Contract Number:: NA0001944

Type:: Accepted Manuscript

Journal Name:: Review of Scientific Instruments

Additional Journal Information:: Journal Volume: 89; Journal Issue: 10; Conference: 22nd Topical Conference on High Temperature Plasma Diagnostics, San Diego, CA (United States), 16-19 Apr 2018; Journal ID: ISSN 0034-6748

Publisher:: American Institute of Physics (AIP)

Research Org:: Univ. of Rochester, Rochester, NY (United States). Lab. for Laser Energetics

Sponsoring Org:: USDOE National Nuclear Security Administration (NNSA)

Country of Publication:: United States

Language:: English

Subject:: 47 OTHER INSTRUMENTATION

OSTI Identifier:: 1460094

Alternate Identifier(s):: OSTI ID: 1459476


                    Edgell, D. H., Katz, J., Turnbull, D. P., and Froula, D. H.. Unabsorbed light beamlets for diagnosing cross-beam energy transfer.  United States: N. p.,  
        Web.  doi:10.1063/1.5036565.

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                    Edgell, D. H., Katz, J., Turnbull, D. P., & Froula, D. H.. Unabsorbed light beamlets for diagnosing cross-beam energy transfer.  United States.  doi:10.1063/1.5036565.

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                    Edgell, D. H., Katz, J., Turnbull, D. P., and Froula, D. H.. 2018.  
        "Unabsorbed light beamlets for diagnosing cross-beam energy transfer".  United States.  
        doi:10.1063/1.5036565.

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@article{osti_1460094,

  title        = {Unabsorbed light beamlets for diagnosing cross-beam energy transfer},

  author       = {Edgell, D. H. and Katz, J. and Turnbull, D. P. and Froula, D. H.},

  abstractNote = {Here, a new diagnostic has been fielded on OMEGA to diagnose cross-beam energy transfer (CBET) during direct-drive implosions. Unabsorbed light from each OMEGA laser beam is imaged as a distinct “spot” onto a gated optical imager. Each spot is in essence the end point of a beamlet of light that originates from different regions of each beam profile and follows a path determined by refraction. The intensity of light in the beamlet varies along its path as a result of absorption and CBET with other beamlets. This diagnostic allows the investigation of the effects of CBET on laser energy from specific locations of the beam profile. The diagnostic records images in two 200-ps time windows and includes a Wollaston prism to split each beamlet into two orthogonal polarizations recorded on separate images, allowing the absolute polarization of each beamlet to be determined. This diagnostic has provided the first evidence of polarization rotation caused by CBET during direct-drive implosions.},

  doi          = {10.1063/1.5036565},

  journal      = {Review of Scientific Instruments},

  number       = 10,

  volume       = 89,

  place        = {United States},

  year         = {2018},

  month        = {7}

}

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Free Publicly Accessible Full Text
This content will become publicly available on July 9, 2019
Publisher's Version of Record
10.1063/1.5036565
https://doi.org/10.1063/1.5036565

Works referenced in this record:

Crossed-beam energy transfer in direct-drive implosions
journal, May 2012

Igumenshchev, I. V.; Seka, W.; Edgell, D. H.
Physics of Plasmas, Vol. 19, Issue 5, Article No. 056314
DOI: 10.1063/1.4718594

Direct-drive laser fusion: Status and prospects
journal, May 1998

Bodner, Stephen E.; Colombant, Denis G.; Gardner, John H.
Physics of Plasmas, Vol. 5, Issue 5, p. 1901-1918
DOI: 10.1063/1.872861

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Title: Unabsorbed light beamlets for diagnosing cross-beam energy transfer

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