Laser-Matter Interactions with a 527 nm Drive

Glenzer, S ; Niemann, C ; Witman, P ; Wegner, P ; Mason, D ; Haynam, C ; Parham, T ; Datte, P

关键词: EFFICIENCY;    HARMONIC GENERATION;    HYDRODYNAMICS;    INERTIAL CONFINEMENT;    LASERS;    MODIFICATIONS;    OPTICS;    PERFORMANCE;    PHYSICS;    PLASMA;    RADIATION TRANSPORT;    SIMULATION;    TARGETS;    US NATIONAL IGNITION FACILITY;   

DOI  :  10.2172/902354
RP-ID  :  UCRL-TR-228230
PID  :  OSTI ID: 902354
Others  :  TRN: US0702929

学科分类：工程和技术（综合）

美国|英语

来源: SciTech Connect

【 摘 要 】

The primary goal of this Exploratory Research is to develop an understanding of laser-matter interactions with 527-nm light (2{omega}) for studies of interest to numerous Laboratory programs including inertial confinement fusion (ICF), material strength, radiation transport, and hydrodynamics. In addition, during the course of this work we will develop the enabling technology and prototype instrumentation to diagnose a high fluence laser beam for energy, power, and near field intensity profile at 2{omega}. Through this Exploratory Research we have established an extensive experimental and modeling data base on laser-matter interaction with 527 nm laser light (2{omega}) in plasma conditions of interest to numerous Laboratory programs. The experiments and the laser-plasma interaction modeling using the code pF3D have shown intensity limits and laser beam conditioning requirements for future 2{omega} laser operations and target physics experiments on the National Ignition Facility (NIF). These findings have set requirements for which present radiation-hydrodynamic simulations indicate the successful generation of relevant pressure regimes in future 2{omega} experiments. To allow these experiments on the NIF, optics and optical mounts were prepared for the 18mm Second Harmonic Generation Crystal (SHG crystal) that would provide the desired high conversion efficiency from 1{omega} to 2{omega}. Supporting experimental activities on NIF included high-energy 1{omega} shots at up to 22kJ/beamline (4MJ full NIF 1{omega} equivalent energy) that demonstrated, in excess, the 1{omega} drive capability of the main laser that is required for 2{omega} operations. Also, a very extensive 3{omega} campaign was completed (see ''The National Ignition Facility Laser Performance Status'' UCRL-JRNL-226553) that demonstrated that not only doubling the laser, but also tripling the laser (a much more difficult and sensitive combination) met our model predictions over a wide range of laser bandwidths and focal spot modification conditions. We have inferred that since we have successful modeled the 3{omega} performance that our 2{omega} model is also validated.