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DOE OSTI · 2573839

Optimization of VISAR Mirrors for NIF Targets

Bhandarkar, Neal [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000305394216)·Manuel, Anastacia M. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0009000201948007)·Celliers, Peter [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000176001227)·Benedetti, Laura Robin [General Atomics, San Diego, CA] (ORCID:0000000160502983)·Werellapatha, Kalpani [General Atomics, San Diego, CA (United States)] (ORCID:0000000293154054)·Gorman, Martin [General Atomics, San Diego, CA (United States)] (ORCID:0000000195676166)·Vennari, Cara [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:000000015160913X)·Palmer, Nathan E. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:000000026005839X)·Kim, Yong-Jae [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:000000021839332X)·Chesser, John [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]·Rangel, Rebeca [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0009000938422325)·Ponce, Darrold [General Atomics, San Diego, CA (United States)]·Ponce, Joshua [General Atomics, San Diego, CA (United States)]·Jensen, Jean [General Atomics, San Diego, CA (United States)]
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Abstract

The velocity interferometer system for any reflector (VISAR) is a key diagnostic at the National Ignition Facility that is used for measuring propagation and velocities of shocks through a sample for several high energy density campaigns. To support simultaneous measurements with VISAR and other diagnostics, optical mirrors are used to divert the VISAR signal off axis from the primary diagnostic line of sight, which can then be used for other measurements. Here, in this study, we describe our work on investigating issues with these mirrors to support complex new target geometries and signal variance due to system aging and more demanding polling rates. This paper also describes the key mitigation efforts performed to improve both the flatness and reflectivity of these commonly used mirrors.

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Bhandarkar, Neal [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000305394216), Manuel, Anastacia M. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0009000201948007), Celliers, Peter [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000176001227), Benedetti, Laura Robin [General Atomics, San Diego, CA] (ORCID:0000000160502983), Werellapatha, Kalpani [General Atomics, San Diego, CA (United States)] (ORCID:0000000293154054), Gorman, Martin [General Atomics, San Diego, CA (United States)] (ORCID:0000000195676166), Vennari, Cara [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:000000015160913X), Palmer, Nathan E. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:000000026005839X), Kim, Yong-Jae [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:000000021839332X), Chesser, John [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Rangel, Rebeca [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0009000938422325), Ponce, Darrold [General Atomics, San Diego, CA (United States)], Ponce, Joshua [General Atomics, San Diego, CA (United States)], Jensen, Jean [General Atomics, San Diego, CA (United States)]. 2025-07-01. Optimization of VISAR Mirrors for NIF Targets. https://doi.org/10.1080/15361055.2025.2509003

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