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arXiv · 1305.6882

Raman backscatter as a remote laser power sensor in high-energy-density plasmas

J. D. Moody·D. J. Strozzi·L. Divol·P. Michel·H. F. Robey·S. LePape·J. Ralph·J. S. Ross·S. H. Glenzer·R. K. Kirkwood·O. L. Landen·B. J. MacGowan·A. Nikroo·E. A. Williams
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Abstract

Stimulated Raman backscatter (SRS) is used as a remote sensor to quantify the instantaneous laser power after transfer from outer to inner cones that cross in a National Ignition Facility (NIF) gas-filled hohlraum plasma. By matching SRS between a shot reducing outer vs a shot reducing inner power we infer that ~half of the incident outer-cone power is transferred to inner cones, for the specific time and wavelength configuration studied. This is the first instantaneous non-disruptive measure of power transfer in an indirect drive NIF experiment using optical measurements.

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J. D. Moody, D. J. Strozzi, L. Divol, P. Michel, H. F. Robey, S. LePape, J. Ralph, J. S. Ross, S. H. Glenzer, R. K. Kirkwood, O. L. Landen, B. J. MacGowan, A. Nikroo, E. A. Williams. 2013-05-29. Raman backscatter as a remote laser power sensor in high-energy-density plasmas. https://doi.org/10.1103/physrevlett.111.025001

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