Unabsorbed light beamlets for diagnosing cross-beam energy transfer

Edgell, D. H.; Katz, J.; Turnbull, D. P.; Froula, D. H.

doi:10.1063/1.5036565

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

Abstract

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];

^[1];

^[1]

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

Publication Date:: 2018-07-09

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

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

OSTI Identifier:: 1460094

Alternate Identifier(s):: OSTI ID: 1459476

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

Grant/Contract Number:: NA0001944

Resource 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)

Country of Publication:: United States

Language:: English

Subject:: 47 OTHER INSTRUMENTATION

Citation Formats


                    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., 2018. 
Web.  https://doi.org/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.  https://doi.org/10.1063/1.5036565

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                    Edgell, D. H., Katz, J., Turnbull, D. P., and Froula, D. H.. Mon .  
"Unabsorbed light beamlets for diagnosing cross-beam energy transfer".  United States.  https://doi.org/10.1063/1.5036565.  https://www.osti.gov/servlets/purl/1460094.

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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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Figures / Tables:

Figure 1: Ray tracing of two beams through a coronal plasma. The solid black circle is the point of deepest possible penetration of any ray (the plasma’s critical-density radius) where the unabsorbed light from any beam is spread over almost the entire 4π solid angle and will reach any diagnosticmore »

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Works referenced in this record:

Mitigation of cross-beam energy transfer: Implication of two-state focal zooming on OMEGA
journal, August 2013

Froula, D. H.; Kessler, T. J.; Igumenshchev, I. V.
Physics of Plasmas, Vol. 20, Issue 8
DOI: 10.1063/1.4818427

Mitigation of cross-beam energy transfer in symmetric implosions on OMEGA using wavelength detuning
journal, June 2017

Edgell, D. H.; Follett, R. K.; Igumenshchev, I. V.
Physics of Plasmas, Vol. 24, Issue 6
DOI: 10.1063/1.4985315

Time-resolved absorption in cryogenic and room-temperature direct-drive implosions
journal, May 2008

Seka, W.; Edgell, D. H.; Knauer, J. P.
Physics of Plasmas, Vol. 15, Issue 5
DOI: 10.1063/1.2898405

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

Irradiation uniformity for high-compression laser-fusion experiments
journal, May 1999

Skupsky, S.; Craxton, R. S.
Physics of Plasmas, Vol. 6, Issue 5
DOI: 10.1063/1.873501

Enhanced reflection of laser light from an expanding plasma
journal, November 1976

Begg, I. M.; Cairns, R. A.
Journal of Physics D: Applied Physics, Vol. 9, Issue 16
DOI: 10.1088/0022-3727/9/16/005

Energy transfer between crossing laser beams
journal, January 1996

Kruer, William L.; Wilks, Scott C.; Afeyan, Bedros B.
Physics of Plasmas, Vol. 3, Issue 1
DOI: 10.1063/1.871863

Direct-drive inertial confinement fusion: A review
journal, November 2015

Craxton, R. S.; Anderson, K. S.; Boehly, T. R.
Physics of Plasmas, Vol. 22, Issue 11
DOI: 10.1063/1.4934714

Laser Compression of Matter to Super-High Densities: Thermonuclear (CTR) Applications
journal, September 1972

Nuckolls, John; Wood, Lowell; Thiessen, Albert
Nature, Vol. 239, Issue 5368, p. 139-142
DOI: 10.1038/239139a0

Figures / Tables found in this record:

Figures/Tables have been extracted from DOE-funded journal article accepted manuscripts.

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Unabsorbed light beamlets for diagnosing coronal density profiles and absorption nonuniformity in direct-drive implosions on OMEGA

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Similar Records

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

Abstract

Citation Formats

Figures / Tables:

Mitigation of cross-beam energy transfer: Implication of two-state focal zooming on OMEGA journal, August 2013

Mitigation of cross-beam energy transfer in symmetric implosions on OMEGA using wavelength detuning journal, June 2017

Time-resolved absorption in cryogenic and room-temperature direct-drive implosions journal, May 2008

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

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

Irradiation uniformity for high-compression laser-fusion experiments journal, May 1999

Enhanced reflection of laser light from an expanding plasma journal, November 1976

Energy transfer between crossing laser beams journal, January 1996

Direct-drive inertial confinement fusion: A review journal, November 2015

Laser Compression of Matter to Super-High Densities: Thermonuclear (CTR) Applications journal, September 1972

Mitigation of cross-beam energy transfer: Implication of two-state focal zooming on OMEGA
journal, August 2013

Mitigation of cross-beam energy transfer in symmetric implosions on OMEGA using wavelength detuning
journal, June 2017

Time-resolved absorption in cryogenic and room-temperature direct-drive implosions
journal, May 2008

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

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

Irradiation uniformity for high-compression laser-fusion experiments
journal, May 1999

Enhanced reflection of laser light from an expanding plasma
journal, November 1976

Energy transfer between crossing laser beams
journal, January 1996

Direct-drive inertial confinement fusion: A review
journal, November 2015

Laser Compression of Matter to Super-High Densities: Thermonuclear (CTR) Applications
journal, September 1972