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

Unabsorbed light beamlets for diagnosing cross-beam energy transfer

Journal Article · Mon Jul 09 00:00:00 EDT 2018 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.5036565· OSTI ID:1460094

Edgell, D. H. ^[1]; Katz, J. ^[2]; ^[2]; ^[2]

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

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.

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

Sponsoring Organization:: USDOE; USDOE National Nuclear Security Administration (NNSA)

Grant/Contract Number:: NA0001944

OSTI ID:: 1460094

Alternate ID(s):: OSTI ID: 1459476

Report Number(s):: 2017-258, 2374; 2017-258, 2374, 1416

Journal Information:: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 10 Vol. 89; ISSN 0034-6748

Publisher:: American Institute of Physics (AIP)Copyright Statement

Country of Publication:: United States

Language:: English

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