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Title: Fabrication, characterization, and modeling of comixed films for NXS calibration targets [Fabrication and metrology of the NXS calibration targets]

Abstract

In 2014/2015 at the Omega laser facility, several experiments took place to calibrate the National Ignition Facility (NIF) X-ray spectrometer (NXS), which is used for high-resolution time-resolved spectroscopic experiments at NIF. The spectrometer allows experimentalists to measure the X-ray energy emitted from high-energy targets, which is used to understand key data such as mixing of materials in highly compressed fuel. The purpose of the experiments at Omega was to obtain information on the instrument performance and to deliver an absolute photometric calibration of the NXS before it was deployed at NIF. The X-ray emission sources fabricated for instrument calibration were 1-mm fused silica spheres with precisely known alloy composition coatings of Si/Ag/Mo, Ti/Cr/Ag, Cr/Ni/Zn, and Zn/Zr, which have emission in the 2- to 18-keV range. Critical to the spectrometer calibration is a known atomic composition of elements with low uncertainty for each calibration sphere. This study discusses the setup, fabrication, and precision metrology of these spheres as well as some interesting findings on the ternary magnetron-sputtered alloy structure.

Authors:
 [1];  [1];  [1];  [1];  [2];  [3];  [3];  [3]
  1. General Atomics, San Diego, CA (United States)
  2. Univ. of Rochester, Rochester, NY (United States). Lab. for Laser Energetics
  3. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1357353
Report Number(s):
LLNL-JRNL-725788
Journal ID: ISSN 1536-1055; TRN: US1702161
Grant/Contract Number:
AC52-07NA27344
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Fusion Science and Technology
Additional Journal Information:
Journal Volume: 70; Journal Issue: 2; Journal ID: ISSN 1536-1055
Publisher:
American Nuclear Society
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; 36 MATERIALS SCIENCE; 70 PLASMA PHYSICS AND FUSION; National Ignition Facility; X-ray spectrometer; fabrication

Citation Formats

Jaquez, Javier, Farrell, Mike, Huang, Haibo, Nikroo, Abbas, Regan, Sean, Fournier, Kevin, Garcia, Maria Alejandra Barrios, and Perez, Frederic. Fabrication, characterization, and modeling of comixed films for NXS calibration targets [Fabrication and metrology of the NXS calibration targets]. United States: N. p., 2016. Web. doi:10.13182/FST15-247.
Jaquez, Javier, Farrell, Mike, Huang, Haibo, Nikroo, Abbas, Regan, Sean, Fournier, Kevin, Garcia, Maria Alejandra Barrios, & Perez, Frederic. Fabrication, characterization, and modeling of comixed films for NXS calibration targets [Fabrication and metrology of the NXS calibration targets]. United States. doi:10.13182/FST15-247.
Jaquez, Javier, Farrell, Mike, Huang, Haibo, Nikroo, Abbas, Regan, Sean, Fournier, Kevin, Garcia, Maria Alejandra Barrios, and Perez, Frederic. 2016. "Fabrication, characterization, and modeling of comixed films for NXS calibration targets [Fabrication and metrology of the NXS calibration targets]". United States. doi:10.13182/FST15-247. https://www.osti.gov/servlets/purl/1357353.
@article{osti_1357353,
title = {Fabrication, characterization, and modeling of comixed films for NXS calibration targets [Fabrication and metrology of the NXS calibration targets]},
author = {Jaquez, Javier and Farrell, Mike and Huang, Haibo and Nikroo, Abbas and Regan, Sean and Fournier, Kevin and Garcia, Maria Alejandra Barrios and Perez, Frederic},
abstractNote = {In 2014/2015 at the Omega laser facility, several experiments took place to calibrate the National Ignition Facility (NIF) X-ray spectrometer (NXS), which is used for high-resolution time-resolved spectroscopic experiments at NIF. The spectrometer allows experimentalists to measure the X-ray energy emitted from high-energy targets, which is used to understand key data such as mixing of materials in highly compressed fuel. The purpose of the experiments at Omega was to obtain information on the instrument performance and to deliver an absolute photometric calibration of the NXS before it was deployed at NIF. The X-ray emission sources fabricated for instrument calibration were 1-mm fused silica spheres with precisely known alloy composition coatings of Si/Ag/Mo, Ti/Cr/Ag, Cr/Ni/Zn, and Zn/Zr, which have emission in the 2- to 18-keV range. Critical to the spectrometer calibration is a known atomic composition of elements with low uncertainty for each calibration sphere. This study discusses the setup, fabrication, and precision metrology of these spheres as well as some interesting findings on the ternary magnetron-sputtered alloy structure.},
doi = {10.13182/FST15-247},
journal = {Fusion Science and Technology},
number = 2,
volume = 70,
place = {United States},
year = 2016,
month = 8
}

Journal Article:
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