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Goodarzi S, Levesque JM, Merritt EC, Sauppe JP, Montgomery DS, Loomis EN, Dunkley NK, Keiter PA. A comparison of past and present computational methods for shape analysis of double-shell x-ray radiographs. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:2887930. [PMID: 37133345 DOI: 10.1063/5.0123931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 04/15/2023] [Indexed: 05/04/2023]
Abstract
Implosion symmetry is a key requirement in achieving a robust burning plasma in inertial confinement fusion experiments. In double-shell capsule implosions, we are interested in the shape of the inner shell as it pushes on the fuel. Shape analysis is a popular technique for studying said symmetry during implosion. Combinations of filtering and contour-finding algorithms are studied for their promise in reliably recovering Legendre shape coefficients from synthetic radiographs of double-shell capsules with applied levels of noise. A radial lineout max(slope) method when used on an image pre-filtered with non-local means and a variant of the marching squares algorithm are able to recover p0, p2, and p4 maxslope Legendre shape coefficients with mean pixel discrepancy errors of 2.81 and 3.06, respectively, for the noisy synthetic radiographs we consider. This improves upon prior radial lineout methods paired with Gaussian filtering, which we show to be unreliable and whose performance is dependent on input parameters that are difficult to estimate.
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Affiliation(s)
- Saba Goodarzi
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | | | | | - Joshua P Sauppe
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | | | - Eric N Loomis
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Noah K Dunkley
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Paul A Keiter
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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Li W, Mu B, Ren K, Xu J, Chen L, Li M, Xu X, Wang X, Liu S, Yi R, Zhang X, Dong J, Wang F. Development of a quasi-coaxis dual-energy flat spectral response X-ray imaging instrument for measuring hotspot electron temperature. OPTICS EXPRESS 2022; 30:8777-8793. [PMID: 35299323 DOI: 10.1364/oe.454237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
The measurement of hotspot electron temperature is a paramount technique of implosion physics research in inertial confinement fusion. This study proposes a novel quasi-coaxis dual-energy flat spectral response high-resolution X-ray imaging instrument comprising a dual-channel total-reflection Kirkpatrick-Baez microscope and two flat non-periodic multilayer mirrors, which can image at 6.4 ± 0.5 and 9.67 ± 0.5 keV simultaneously. Various theoretical simulations were performed to verify the performance and feasibility of the imaging instrument, which was assembled and characterized in a laboratory. Experimental results show that the imaging instrument could achieve a high spatial resolution of 5 µm in a ± 150 µm field of view (FOV), the root mean square(RMS) deviation values of the measured reflection efficiency are 1.71% and 1.82% for the 6.4 keV and 9.67 keV imaging channels, respectively, in the ± 150 µm FOV.
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3
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Schlossberg DJ, Grim GP, Casey DT, Moore AS, Nora R, Bachmann B, Benedetti LR, Bionta RM, Eckart MJ, Field JE, Fittinghoff DN, Gatu Johnson M, Geppert-Kleinrath V, Hartouni EP, Hatarik R, Hsing WW, Jarrott LC, Khan SF, Kilkenny JD, Landen OL, MacGowan BJ, Mackinnon AJ, Meaney KD, Munro DH, Nagel SR, Pak A, Patel PK, Spears BK, Volegov PL, Young CV. Observation of Hydrodynamic Flows in Imploding Fusion Plasmas on the National Ignition Facility. PHYSICAL REVIEW LETTERS 2021; 127:125001. [PMID: 34597087 DOI: 10.1103/physrevlett.127.125001] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 06/06/2021] [Accepted: 07/08/2021] [Indexed: 06/13/2023]
Abstract
Inertial confinement fusion implosions designed to have minimal fluid motion at peak compression often show significant linear flows in the laboratory, attributable per simulations to percent-level imbalances in the laser drive illumination symmetry. We present experimental results which intentionally varied the mode 1 drive imbalance by up to 4% to test hydrodynamic predictions of flows and the resultant imploded core asymmetries and performance, as measured by a combination of DT neutron spectroscopy and high-resolution x-ray core imaging. Neutron yields decrease by up to 50%, and anisotropic neutron Doppler broadening increases by 20%, in agreement with simulations. Furthermore, a tracer jet from the capsule fill-tube perturbation that is entrained by the hot-spot flow confirms the average flow speeds deduced from neutron spectroscopy.
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Affiliation(s)
- D J Schlossberg
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - G P Grim
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - D T Casey
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - A S Moore
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - R Nora
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - B Bachmann
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - L R Benedetti
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - R M Bionta
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - M J Eckart
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - J E Field
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - D N Fittinghoff
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - M Gatu Johnson
- Massachusetts Institute of Technology Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | | | - E P Hartouni
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - R Hatarik
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - W W Hsing
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - L C Jarrott
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - S F Khan
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - J D Kilkenny
- General Atomics, La Jolla, California 92121, USA
| | - O L Landen
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - B J MacGowan
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - A J Mackinnon
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - K D Meaney
- Los Alamos National Laboratory, Los Alamos, New Mexico 87544, USA
| | - D H Munro
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - S R Nagel
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - A Pak
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - P K Patel
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - B K Spears
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - P L Volegov
- Los Alamos National Laboratory, Los Alamos, New Mexico 87544, USA
| | - C V Young
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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Khan SF, Jarrott LC, Patel PK, Izumi N, Ma T, MacPhee AG, Hatch B, Landen OL, Heinmiller J, Kilkenny JD, Bradley DK. Implementing time resolved electron temperature capability at the NIF using a streak camera. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:10K117. [PMID: 30399814 DOI: 10.1063/1.5039382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 09/05/2018] [Indexed: 06/08/2023]
Abstract
A new capability at the National Ignition Facility (NIF) has been implemented to measure the temperature of x-ray emitting sources. Although it is designed primarily for Inertial Confinement Fusion (ICF), it can be used for any hot emitting source that is well modeled. The electron temperature (Te) of the hot spot within the core of imploded ICF capsules is an effective indicator of implosion performance. Currently, there are spatially and temporally integrated Te inferences using image plates. A temporally resolved measurement of Te will help elucidate the mechanisms for hot spot heating and cooling such as conduction to fuel, alpha-heating, mix, and radiative losses. To determine the temporally resolved Te of hot spots, specific filters are added to an existing x-ray streak camera "streaked polar instrumentation for diagnosing energetic radiation" to probe the emission spectrum during the x-ray burn history of implosions at the NIF. One of the difficulties in inferring the hot spot temperature is the attenuation of the emission due to opacity from the shell and fuel. Therefore, a series of increasingly thick titanium filters were implemented to isolate the emission in specific energy regions that are sensitive to temperatures above 3 keV while not significantly influenced by the shell/fuel attenuation. Additionally, a relatively thin zinc filter was used to measure the contribution of colder emission sources. Since the signal levels of the emission through the thicker filters are relatively poor, a dual slit (aperture) was designed to increase the detected signal at the higher end of the spectrum. Herein, the design of the filters and slit is described, an overview of the solving technique is provided, and the initial electron temperature results are reported.
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Affiliation(s)
- S F Khan
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - L C Jarrott
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - P K Patel
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - N Izumi
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - T Ma
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - A G MacPhee
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - B Hatch
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - O L Landen
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - J Heinmiller
- Nevada National Security Site, Livermore, California 94551, USA
| | - J D Kilkenny
- General Atomics, San Diego, California 92121, USA
| | - D K Bradley
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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