国家点火装置的散射光时间历程诊断套件。

The Scattered Light Time-history Diagnostic suite at the National Ignition Facility.

作者信息

Rosenberg M J, Hernandez J E, Butler N, Filkins T, Bahr R E, Jungquist R K, Bedzyk M, Swadling G, Ross J S, Michel P, Lemos N, Eichmiller J, Sommers R, Nyholm P, Boni R, Marozas J A, Craxton R S, McKenty P W, Sharma A, Radha P B, Froula D H, Datte P, Gorman M, Moody J D, Heinmiller J M, Fornes J, Hillyard P, Regan S P

机构信息

Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.

Lawrence Livermore National Laboratory, Livermore, California 94550, USA.

出版信息

Rev Sci Instrum. 2021 Mar 1;92(3):033511. doi: 10.1063/5.0040558.

DOI:10.1063/5.0040558

PMID:33820108

Abstract

The Scattered Light Time-history Diagnostic (SLTD) is being implemented at the National Ignition Facility (NIF) to greatly expand the angular coverage of absolute scattered-light measurements for direct- and indirect-drive inertial confinement fusion (ICF) experiments. The SLTD array will ultimately consist of 15 units mounted at a variety of polar and azimuthal angles on the NIF target chamber, complementing the existing NIF backscatter suite. Each SLTD unit collects and diffuses scattered light onto a set of three optical fibers, which transport the light to filtered photodiodes to measure scattered light in different wavelength bands: stimulated Brillouin scattering (350 nm-352 nm), stimulated Raman scattering (430 nm-760 nm), and ω/2 (695 nm-745 nm). SLTD measures scattered light with a time resolution of ∼1 ns and a signal-to-noise ratio of up to 500. Currently, six units are operational and recording data. Measurements of the angular dependence of scattered light will strongly constrain models of laser energy coupling in ICF experiments and allow for a more robust inference of the total laser energy coupled to implosions.

摘要

国家点火装置（NIF）正在实施散射光时间历程诊断（SLTD），以大幅扩大直接驱动和间接驱动惯性约束聚变（ICF）实验中绝对散射光测量的角度覆盖范围。SLTD阵列最终将由15个单元组成，这些单元以各种极角和方位角安装在NIF靶室上，作为现有NIF背散射套件的补充。每个SLTD单元收集散射光并将其扩散到一组三根光纤上，这些光纤将光传输到滤波光电二极管，以测量不同波长波段的散射光：受激布里渊散射（350纳米 - 352纳米）、受激拉曼散射（430纳米 - 760纳米）和ω/2（695纳米 - 745纳米）。SLTD以约1纳秒的时间分辨率和高达500的信噪比测量散射光。目前，六个单元正在运行并记录数据。散射光角度依赖性的测量将有力地约束ICF实验中激光能量耦合的模型，并允许更可靠地推断耦合到内爆的总激光能量。