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Title: Comparison of implosion core metrics: A 10 ps dilation X-ray imager vs a 100 ps gated microchannel plate [Comparison of implosion core shape observations, 10 ps dilation X-ray imager vs 100 ps gated microchannel plate]

Abstract

The dilation x-ray imager (DIXI) is a high-speed x-ray framing camera that uses the pulse-dilation technique to achieve a temporal resolution of less than 10 ps. This is a 10× improvement over conventional framing cameras currently employed on the National Ignition Facility (NIF) (100 ps resolution), and otherwise only achievable with 1D streaked imaging. A side effect of the dramatically reduced gate width is the comparatively lower detected signal level. Therefore we implement a Poisson noise reduction with non-local principal component analysis method to improve the robustness of the DIXI data analysis. Furthermore, we present results on ignition-relevant experiments at the NIF using DIXI. In particular we focus on establishing that/when DIXI gives reliable shape metrics (P 0, P 2 and P 4 Legendre modes, and their temporal evolution/swings).

Authors:
ORCiD logo [1];  [1];  [1];  [2];  [1];  [1]; ORCiD logo [3];  [1];  [1]
  1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  2. General Atomics, San Diego, CA (United States)
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1336985
Report Number(s):
LLNL-PROC-694130
Journal ID: ISSN 0034-6748; RSINAK
Grant/Contract Number:
AC52-07NA27344
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Review of Scientific Instruments
Additional Journal Information:
Journal Volume: 87; Journal Issue: 11; Conference: Proceedings of the 21st Topical Conference on High-Temperature Plasma Diagnostics, Madison, WI (United States), 5-9 Jun 2016; Journal ID: ISSN 0034-6748
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

Citation Formats

Nagel, S. R., Benedetti, L. R., Bradley, D. K., Hilsabeck, T. J., Izumi, N., Khan, S., Kyrala, G. A., Ma, T., and Pak, A. Comparison of implosion core metrics: A 10 ps dilation X-ray imager vs a 100 ps gated microchannel plate [Comparison of implosion core shape observations, 10 ps dilation X-ray imager vs 100 ps gated microchannel plate]. United States: N. p., 2016. Web. doi:10.1063/1.4959917.
Nagel, S. R., Benedetti, L. R., Bradley, D. K., Hilsabeck, T. J., Izumi, N., Khan, S., Kyrala, G. A., Ma, T., & Pak, A. Comparison of implosion core metrics: A 10 ps dilation X-ray imager vs a 100 ps gated microchannel plate [Comparison of implosion core shape observations, 10 ps dilation X-ray imager vs 100 ps gated microchannel plate]. United States. doi:10.1063/1.4959917.
Nagel, S. R., Benedetti, L. R., Bradley, D. K., Hilsabeck, T. J., Izumi, N., Khan, S., Kyrala, G. A., Ma, T., and Pak, A. Fri . "Comparison of implosion core metrics: A 10 ps dilation X-ray imager vs a 100 ps gated microchannel plate [Comparison of implosion core shape observations, 10 ps dilation X-ray imager vs 100 ps gated microchannel plate]". United States. doi:10.1063/1.4959917. https://www.osti.gov/servlets/purl/1336985.
@article{osti_1336985,
title = {Comparison of implosion core metrics: A 10 ps dilation X-ray imager vs a 100 ps gated microchannel plate [Comparison of implosion core shape observations, 10 ps dilation X-ray imager vs 100 ps gated microchannel plate]},
author = {Nagel, S. R. and Benedetti, L. R. and Bradley, D. K. and Hilsabeck, T. J. and Izumi, N. and Khan, S. and Kyrala, G. A. and Ma, T. and Pak, A.},
abstractNote = {The dilation x-ray imager (DIXI) is a high-speed x-ray framing camera that uses the pulse-dilation technique to achieve a temporal resolution of less than 10 ps. This is a 10× improvement over conventional framing cameras currently employed on the National Ignition Facility (NIF) (100 ps resolution), and otherwise only achievable with 1D streaked imaging. A side effect of the dramatically reduced gate width is the comparatively lower detected signal level. Therefore we implement a Poisson noise reduction with non-local principal component analysis method to improve the robustness of the DIXI data analysis. Furthermore, we present results on ignition-relevant experiments at the NIF using DIXI. In particular we focus on establishing that/when DIXI gives reliable shape metrics (P0, P2 and P4 Legendre modes, and their temporal evolution/swings).},
doi = {10.1063/1.4959917},
journal = {Review of Scientific Instruments},
number = 11,
volume = 87,
place = {United States},
year = {Fri Aug 05 00:00:00 EDT 2016},
month = {Fri Aug 05 00:00:00 EDT 2016}
}

Journal Article:
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Cited by: 5works
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  • As the yield on implosion shots increases it is expected that the peak x-ray emission reduces to a duration with a FWHM as short as 20 ps for ~7 10 18 neutron yield. However, the temporal resolution of currently used gated x-ray imagers on the NIF is 40-100 ps. We discuss the benefits of the higher temporal resolution for the NIF and present performance measurements for DIXI, which utilizes pulse-dilation technology [1] to achieve x-ray imaging with temporal gate times below 10 ps. Lastly, the measurements were conducted using the COMET laser, which is part of the Jupiter Laser Facilitymore » at the Lawrence Livermore National Laboratory.« less
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  • As the yield on implosion shots increases it is expected that the peak x-ray emission reduces to a duration with a FWHM as short as 20 ps for {approx}7 Multiplication-Sign 10{sup 18} neutron yield. However, the temporal resolution of currently used gated x-ray imagers on the NIF is 40-100 ps. We discuss the benefits of the higher temporal resolution for the NIF and present performance measurements for dilation x-ray imager, which utilizes pulse-dilation technology [T. J. Hilsabeck et al., Rev. Sci. Instrum. 81, 10E317 (2010)] to achieve x-ray imaging with temporal gate times below 10 ps. The measurements were conductedmore » using the COMET laser, which is part of the Jupiter Laser Facility at the Lawrence Livermore National Laboratory.« less
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