1
|
Xu H, Wen S, Si H, Huang Q, Zhang Z, Zhang F, Yi S, Wang Z. Direct multiple monochromatic x-ray imaging with a pinhole array and a laterally graded multilayer mirror. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2024; 95:063504. [PMID: 38904544 DOI: 10.1063/5.0187365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 06/03/2024] [Indexed: 06/22/2024]
Abstract
Multiple monochromatic x-ray imaging (MMI) is a technique for diagnosing the emission spectra of tracer elements in laser-driven inertial confinement fusion experiments. This study proposes an MMI method that combines a simple pinhole array with a laterally graded multilayer mirror. The method directly obtains multiple monochromatic x-ray images by regulating the multilayer thickness in different mirror positions to compensate for the energy-broadening effect. This paper presents a comprehensive design scheme, the multilayer fabrication and experimental verification of the gradient MMI imaging performance. The experimental results show that the method achieves monochromatic imaging with a spectral resolution of ∼70-90 eV in several keV energy regions. This paper presents a practical diagnostic approach for directly and synchronously capturing the spatial, temporal, and spectral information of laser plasma x rays.
Collapse
Affiliation(s)
- Hao Xu
- MOE Key Laboratory of Advanced Micro-Structured Materials, No. 1239 Siping Road, 200092 Shanghai, China
- School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
| | - Shengyou Wen
- MOE Key Laboratory of Advanced Micro-Structured Materials, No. 1239 Siping Road, 200092 Shanghai, China
- School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
| | - Haoxuan Si
- MOE Key Laboratory of Advanced Micro-Structured Materials, No. 1239 Siping Road, 200092 Shanghai, China
- School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
| | - Qiushi Huang
- MOE Key Laboratory of Advanced Micro-Structured Materials, No. 1239 Siping Road, 200092 Shanghai, China
- School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
| | - Zhe Zhang
- MOE Key Laboratory of Advanced Micro-Structured Materials, No. 1239 Siping Road, 200092 Shanghai, China
- School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
| | - Feng Zhang
- Research Center of Laser Fusion, CAEP, Mianyang 21900, China
| | - Shengzhen Yi
- MOE Key Laboratory of Advanced Micro-Structured Materials, No. 1239 Siping Road, 200092 Shanghai, China
- School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
| | - Zhanshan Wang
- MOE Key Laboratory of Advanced Micro-Structured Materials, No. 1239 Siping Road, 200092 Shanghai, China
- School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
| |
Collapse
|
2
|
Gao L, Kraus BF, Hill KW, Schneider MB, Christopherson A, Bachmann B, Bitter M, Efthimion P, Pablant N, Betti R, Thomas C, Thorn D, MacPhee AG, Khan S, Kauffman R, Liedahl D, Chen H, Bradley D, Kilkenny J, Lahmann B, Stambulchik E, Maron Y. Hot Spot Evolution Measured by High-Resolution X-Ray Spectroscopy at the National Ignition Facility. PHYSICAL REVIEW LETTERS 2022; 128:185002. [PMID: 35594117 DOI: 10.1103/physrevlett.128.185002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 01/19/2022] [Accepted: 03/16/2022] [Indexed: 06/15/2023]
Abstract
Evolution of the hot spot plasma conditions was measured using high-resolution x-ray spectroscopy at the National Ignition Facility. The capsules were filled with DD gas with trace levels of Kr and had either a high-density-carbon (HDC) ablator or a tungsten (W)-doped HDC ablator. Time-resolved measurement of the Kr Heβ spectra, absolutely calibrated by a simultaneous time-integrated measurement, allows inference of the electron density and temperature through observing Stark broadening and the relative intensities of dielectronic satellites. By matching the calculated hot spot emission using a collisional-radiative code to experimental observations, the hot spot size and areal density are determined. These advanced spectroscopy techniques further reveal the effect of W dopant in the ablator on the hot spot parameters for their improved implosion performance.
Collapse
Affiliation(s)
- Lan Gao
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - B F Kraus
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - K W Hill
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - M B Schneider
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - A Christopherson
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - B Bachmann
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - M Bitter
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - P Efthimion
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - N Pablant
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - R Betti
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - C Thomas
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - D Thorn
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - A G MacPhee
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - S Khan
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - R Kauffman
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - D Liedahl
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - H Chen
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - D Bradley
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - J Kilkenny
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - B Lahmann
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - E Stambulchik
- Faculty of Physics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Y Maron
- Faculty of Physics, Weizmann Institute of Science, Rehovot 7610001, Israel
| |
Collapse
|
3
|
Kraus BF, Gao L, Hill KW, Bitter M, Efthimion PC, Gomez TA, Moreau A, Hollinger R, Wang S, Song H, Rocca JJ, Mancini RC. Solid-Density Ion Temperature from Redshifted and Double-Peaked Stark Line Shapes. PHYSICAL REVIEW LETTERS 2021; 127:205001. [PMID: 34860067 DOI: 10.1103/physrevlett.127.205001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 08/27/2021] [Accepted: 10/01/2021] [Indexed: 06/13/2023]
Abstract
Heβ spectral line shapes are important for diagnosing temperature and density in many dense plasmas. This work presents Heβ line shapes measured with high spectral resolution from solid-density plasmas with minimized gradients. The line shapes show hallmark features of Stark broadening, including quantifiable redshifts and double-peaked structure with a significant dip between the peaks; these features are compared to models through a Markov chain Monte Carlo framework. Line shape theory using the dipole approximation can fit the width and peak separation of measured line shapes, but it cannot resolve an ambiguity between electron density n_{e} and ion temperature T_{i}, since both parameters influence the strength of quasistatic ion microfields. Here a line shape model employing a full Coulomb interaction for the electron broadening computes self-consistent line widths and redshifts through the monopole term; redshifts have different dependence on plasma parameters and thus resolve the n_{e}-T_{i} ambiguity. The measured line shapes indicate densities that are 80-100% of solid, identifying a regime of highly ionized but well-tamped plasma. This analysis also provides the first strong evidence that dense ions and electrons are not in thermal equilibrium, despite equilibration times much shorter than the duration of x-ray emission; cooler ions may arise from nonclassical thermalization rates or anomalous energy transport. The experimental platform and diagnostic technique constitute a promising new approach for studying ion-electron equilibration in dense plasmas.
Collapse
Affiliation(s)
- B F Kraus
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08544, USA
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - Lan Gao
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - K W Hill
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - M Bitter
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - P C Efthimion
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - T A Gomez
- Sandia National Laboratory, Albuquerque, New Mexico 87123, USA
| | - A Moreau
- Electrical and Computer Engineering Department, Colorado State University, Fort Collins, Colorado 80523, USA
| | - R Hollinger
- Electrical and Computer Engineering Department, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Shoujun Wang
- Electrical and Computer Engineering Department, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Huanyu Song
- Electrical and Computer Engineering Department, Colorado State University, Fort Collins, Colorado 80523, USA
| | - J J Rocca
- Electrical and Computer Engineering Department, Colorado State University, Fort Collins, Colorado 80523, USA
- Physics Department, Colorado State University, Fort Collins, Colorado 80523, USA
| | - R C Mancini
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| |
Collapse
|
4
|
Carpenter KR, Mancini RC, Harding EC, Harvey-Thompson AJ, Geissel M, Weis MR, Hansen SB, Peterson KJ, Rochau GA. Temperature distributions and gradients in laser-heated plasmas relevant to magnetized liner inertial fusion. Phys Rev E 2020; 102:023209. [PMID: 32942382 DOI: 10.1103/physreve.102.023209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 07/28/2020] [Indexed: 06/11/2023]
Abstract
We present two-dimensional temperature measurements of magnetized and unmagnetized plasma experiments performed at Z relevant to the preheat stage in magnetized liner inertial fusion. The deuterium gas fill was doped with a trace amount of argon for spectroscopy purposes, and time-integrated spatially resolved spectra and narrow-band images were collected in both experiments. The spectrum and image data were included in two separate multiobjective analysis methods to extract the electron temperature spatial distribution T_{e}(r,z). The results indicate that the magnetic field increases T_{e}, the axial extent of the laser heating, and the magnitude of the radial temperature gradients. Comparisons with simulations reveal that the simulations overpredict the extent of the laser heating and underpredict the temperature. Temperature gradient scale lengths extracted from the measurements also permit an assessment of the importance of nonlocal heat transport.
Collapse
Affiliation(s)
- K R Carpenter
- Physics Department, University of Nevada, Reno, Nevada 89557, USA
| | - R C Mancini
- Physics Department, University of Nevada, Reno, Nevada 89557, USA
| | - E C Harding
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - A J Harvey-Thompson
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - M Geissel
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - M R Weis
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - S B Hansen
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - K J Peterson
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - G A Rochau
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| |
Collapse
|
5
|
Wang RR, An HH, Guo EF, Fang ZH, Xie ZY, Jia G, Wang W. Elliptically bent crystal x-ray spectrometer for time-resolved laser plasma experiments. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:093109. [PMID: 30278722 DOI: 10.1063/1.5029462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 08/30/2018] [Indexed: 06/08/2023]
Abstract
Measuring time-resolved spectra is crucial in inertial confinement fusion and radiation source development experiments. An elliptically bent crystal spectrometer is designed to measure X-rays in the range of 2.5-11.0 keV, which was achieved using four different lattice spacings of 0.8512, 0.6687, 0.4246, and 0.2749 nm with spectral resolution E/δE of ∼500. The X-rays emitted from a source at one focus of the ellipse undergo Bragg reflection off a crystal and pass through the second focus of the ellipse to a streak camera slit with 18-mm length and 80-μm width to generate a time-resolved spectrum. An alignment method for the time-resolved spectrometer was developed with the straight line connecting the centers of the two small holes on the fabricated substrate being the axis of the ellipse, thus allowing the spacing between the source and the elliptical crystal to be tuned to couple with the streak camera. The time-resolved spectrometer's performance was experimentally tested at the Shenguang II laser facility. The results indicate that its performance is close to that predicted theoretically.
Collapse
Affiliation(s)
- R R Wang
- Shanghai Institute of Laser Plasma, Shanghai 201800, China
| | - H H An
- Shanghai Institute of Laser Plasma, Shanghai 201800, China
| | - E F Guo
- Shanghai Institute of Laser Plasma, Shanghai 201800, China
| | - Z H Fang
- Shanghai Institute of Laser Plasma, Shanghai 201800, China
| | - Z Y Xie
- Shanghai Institute of Laser Plasma, Shanghai 201800, China
| | - G Jia
- Shanghai Institute of Laser Plasma, Shanghai 201800, China
| | - W Wang
- Shanghai Institute of Laser Plasma, Shanghai 201800, China
| |
Collapse
|
6
|
Qing B, Wei M, Yang G, Zhang Z, Zhao Y, Xiong G, Lv M, Hu Z, Zhang J, Liu S, Yang J. A time-gated multi-channel x-ray crystal spectrometer on the Shenguang-III laser facility. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:083108. [PMID: 30184675 DOI: 10.1063/1.5033359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 07/29/2018] [Indexed: 06/08/2023]
Abstract
An eight-channel x-ray flat crystal spectrometer was developed for high energy density physics research at the Shenguang-III (SG-III) laser facility. The spectrometer uses trihydroxymethylaminomethane crystals (2d = 8.78 Å) to record Ti K-shell emission in the photon energy range of 4.65-5.05 keV. The spectrometer couples to an x-ray framing camera to achieve time-resolution. This has four microstrips, and each strip records two snapshots of the emission image. Based on the intersection positioning system with a dual-charge coupled device, the alignment system is easily operated and efficient. The instrument was tested and used for Au hohlraum plasma diagnosis experiments on SG-III. The He-α line and its Li-like satellites and the Ly-α line of a Ti tracer were detected, from which the spectral resolution of the instrument was analyzed. The spectral resolution E/ΔE at the Ti He-α line ranges from about 500 to 880 and mainly limited by the x-ray source size.
Collapse
Affiliation(s)
- Bo Qing
- Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China
| | - Minxi Wei
- Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China
| | - Guohong Yang
- Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China
| | - Zhiyu Zhang
- Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China
| | - Yang Zhao
- Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China
| | - Gang Xiong
- Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China
| | - Min Lv
- Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China
| | - Zhimin Hu
- Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China
| | - Jiyan Zhang
- Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China
| | - Shenye Liu
- Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China
| | - Jiamin Yang
- Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China
| |
Collapse
|
7
|
Knapp PF, Ball C, Austin K, Hansen SB, Kernaghan MD, Lake PW, Ampleford DJ, McPherson LA, Sandoval D, Gard P, Wu M, Bourdon C, Rochau GA, McBride RD, Sinars DB. A new time and space resolved transmission spectrometer for research in inertial confinement fusion and radiation source development. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:013504. [PMID: 28147637 DOI: 10.1063/1.4973914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We describe the design and function of a new time and space resolved x-ray spectrometer for use in Z-pinch inertial confinement fusion and radiation source development experiments. The spectrometer is designed to measure x-rays in the range of 0.5-1.5 Å (8-25 keV) with a spectral resolution λ/Δλ ∼ 400. The purpose of this spectrometer is to measure the time- and one-dimensional space-dependent electron temperature and density during stagnation. These relatively high photon energies are required to escape the dense plasma created at stagnation and to obtain sensitivity to electron temperatures ≳3 keV. The spectrometer is of the Cauchois type, employing a large 30 × 36 mm2, transmissive quartz optic for which a novel solid beryllium holder was designed. The performance of the crystal was verified using offline tests, and the integrated system was tested using experiments on the Z pulsed power accelerator.
Collapse
Affiliation(s)
- P F Knapp
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - C Ball
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - K Austin
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - S B Hansen
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - M D Kernaghan
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - P W Lake
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - D J Ampleford
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - L A McPherson
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - D Sandoval
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - P Gard
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - M Wu
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - C Bourdon
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G A Rochau
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - R D McBride
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - D B Sinars
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| |
Collapse
|
8
|
Koch JA, Landen OL, Suter LJ, Masse LP. Simple solution to the Fresnel-Kirchoff diffraction integral for application to refraction-enhanced radiography. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2013; 30:1460-1463. [PMID: 24323163 DOI: 10.1364/josaa.30.001460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We present a simple solution to the Fresnel-Kirchoff diffraction integral that is appropriate for x-ray radiography of strongly absorbing and phase-shifting objects in the geometrical optics regime, where phase contrast enhancements can be considered to be caused by refraction by a semi-opaque object. We demonstrate its accuracy by comparison to brute-force numerical ray trace and diffraction calculations of a representative simulated object, and show excellent agreement for spatial scales corresponding to Fresnel numbers greater than unity. The result represents a significant improvement over approximate formulas typically used in analysis of refraction-enhanced radiographs, particularly for radiography of transient phenomena in objects that strongly refract and show significant absorption.
Collapse
|
9
|
Koch JA, Landen OL, Suter LJ, Masse LP, Clark DS, Ross JS, Mackinnon AJ, Meezan NB, Thomas CA, Ping Y. Refraction-enhanced backlit imaging of axially symmetric inertial confinement fusion plasmas. APPLIED OPTICS 2013; 52:3538-3556. [PMID: 23736240 DOI: 10.1364/ao.52.003538] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Accepted: 04/12/2013] [Indexed: 06/02/2023]
Abstract
X-ray backlit radiographs of dense plasma shells can be significantly altered by refraction of x rays that would otherwise travel straight-ray paths, and this effect can be a powerful tool for diagnosing the spatial structure of the plasma being radiographed. We explore the conditions under which refraction effects may be observed, and we use analytical and numerical approaches to quantify these effects for one-dimensional radial opacity and density profiles characteristic of inertial-confinement fusion (ICF) implosions. We also show how analytical and numerical approaches allow approximate radial plasma opacity and density profiles to be inferred from point-projection refraction-enhanced radiography data. This imaging technique can provide unique data on electron density profiles in ICF plasmas that cannot be obtained using other techniques, and the uniform illumination provided by point-like x-ray backlighters eliminates a significant source of uncertainty in inferences of plasma opacity profiles from area-backlit pinhole imaging data when the backlight spatial profile cannot be independently characterized. The technique is particularly suited to in-flight radiography of imploding low-opacity shells surrounding hydrogen ice, because refraction is sensitive to the electron density of the hydrogen plasma even when it is invisible to absorption radiography. It may also provide an alternative approach to timing shockwaves created by the implosion drive, that are currently invisible to absorption radiography.
Collapse
Affiliation(s)
- Jeffrey A Koch
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Florido R, Mancini RC, Nagayama T, Tommasini R, Delettrez JA, Regan SP, Yaakobi B. Measurements of core and compressed-shell temperature and density conditions in thick-wall target implosions at the OMEGA laser facility. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 83:066408. [PMID: 21797499 DOI: 10.1103/physreve.83.066408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Revised: 04/04/2011] [Indexed: 05/31/2023]
Abstract
A spectroscopic method is discussed to measure core and compressed-shell conditions in thick-wall plastic-shell implosions filled with deuterium and a tracer amount of argon. Simultaneous observation over a broad photon energy range of the argon line emission and the attenuation and self-emission effects of the compressed shell confining the core yields enough information to extract average temperature and density conditions in both core and compressed shell. The spectroscopic analysis also provides an estimate of the target areal density which is an important characteristic of inertial confinement fusion implosions.
Collapse
Affiliation(s)
- R Florido
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | | | | | | | | | | | | |
Collapse
|
11
|
Haugh M, Stewart R. Optimizing the operation of a high resolution vertical Johann spectrometer using a high energy fluorescer x-ray source. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:10E537. [PMID: 21034064 DOI: 10.1063/1.3492421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This paper describes the operation and testing for a vertical Johann spectrometer (VJS) operating in the 13 keV range. The spectrometer is designed to use thin curved mica crystals or thick germanium crystals. The VJS must have a resolution of E/ΔE=3000 or better to measure the Doppler broadening of highly ionized krypton and operate at a small x-ray angle in order to be used as a diagnostic in a laser plasma target chamber. The VJS was aligned, tested, and optimized using a fluorescer type high energy x-ray (HEX) source located at National Security Technologies (NSTec), LLC, in Livermore, CA. The HEX uses a 160 kV x-ray tube to excite fluorescence from various targets. Both rubidium and bismuth fluorescers were used for this effort. This presentation describes the NSTec HEX system and the methods used to optimize and characterize the VJS performance.
Collapse
Affiliation(s)
- Michael Haugh
- National Security Technologies, LLC, 161 S. Vasco Rd., Suite A, Livermore, California 94550, USA
| | | |
Collapse
|
12
|
Nagayama T, Mancini RC, Florido R, Tommasini R, Koch JA, Delettrez JA, Regan SP, Smalyuk VA, Welser-Sherrill LA, Golovkin IE. Comparison of genetic-algorithm and emissivity-ratio analyses of image data from OMEGA implosion cores. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:10E921. [PMID: 19044576 DOI: 10.1063/1.2966370] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Detailed analysis of x-ray narrow-band images from argon-doped deuterium-filled inertial confinement fusion implosion experiments yields information about the temperature spatial structure in the core at the collapse of the implosion. We discuss the analysis of direct-drive implosion experiments at OMEGA, in which multiple narrow-band images were recorded with a multimonochromatic x-ray imaging instrument. The temperature spatial structure is investigated by using the sensitivity of the Ly beta/He beta line emissivity ratio to the temperature. Three analysis methods that consider the argon He beta and Ly beta image data are discussed and the results compared. The methods are based on a ratio of image intensities, ratio of Abel-inverted emissivities, and a search and reconstruction technique driven by a Pareto genetic algorithm.
Collapse
Affiliation(s)
- T Nagayama
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Welser-Sherrill L, Mancini RC, Koch JA, Izumi N, Tommasini R, Haan SW, Haynes DA, Golovkin IE, MacFarlane JJ, Delettrez JA, Marshall FJ, Regan SP, Smalyuk VA, Kyrala G. Spectroscopic determination of temperature and density spatial profiles and mix in indirect-drive implosion cores. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2007; 76:056403. [PMID: 18233772 DOI: 10.1103/physreve.76.056403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2007] [Revised: 09/25/2007] [Indexed: 05/25/2023]
Abstract
In the field of inertial confinement fusion (ICF), work has been consistently progressing in the past decade toward a more fundamental understanding of the plasma conditions in ICF implosion cores. The research presented here represents a substantial evolution in the ability to diagnose plasma temperatures and densities, along with characteristics of mixing between fuel and shell materials. Mixing is a vital property to study and quantify, since it can significantly affect implosion quality. We employ a number of new spectroscopic techniques that allow us to probe these important quantities. The first technique developed is an emissivity analysis, which uses the emissivity ratio of the optically thin Lybeta and Hebeta lines to spectroscopically extract temperature profiles, followed by the solution of emissivity equations to infer density profiles. The second technique, an intensity analysis, models the radiation transport through the implosion core. The nature of the intensity analysis allows us to use an optically thick line, the Lyalpha, to extract information on mixing near the core edge. With this work, it is now possible to extract directly from experimental data not only detailed temperature and density maps of the core, but also spatial mixing profiles.
Collapse
Affiliation(s)
- L Welser-Sherrill
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
MacFarlane JJ, Golovkin IE, Mancini RC, Welser LA, Bailey JE, Koch JA, Mehlhorn TA, Rochau GA, Wang P, Woodruff P. Dopant radiative cooling effects in indirect-drive Ar-doped capsule implosion experiments. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 72:066403. [PMID: 16486066 DOI: 10.1103/physreve.72.066403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2005] [Revised: 09/14/2005] [Indexed: 05/06/2023]
Abstract
We present results from simulations performed to investigate the effects of dopant radiative cooling in inertial confinement fusion indirect-drive capsule implosion experiments. Using a one-dimensional radiation-hydrodynamics code that includes inline collisional-radiative modeling, we compute in detail the non-local thermodynamic equilibrium atomic kinetics and spectral characteristics for Ar-doped DD fuel. Specifically, we present results from a series of calculations in which the concentration of the Ar is varied, and examine the sensitivity of the fuel conditions (e.g., electron temperature) and neutron yield to the Ar dopant concentration. Simulation results are compared with data obtained in OMEGA indirect-drive experiments in which monochromatic imaging and spectral measurements of Ar Hebeta and Lybeta line emission were recorded. The incident radiation drive on the capsule is computed with a three-dimensional view factor code using the laser beam pointings and powers from the OMEGA experiments. We also examine the sensitivity of the calculated compressed core electron temperatures and neutron yields to the radiation drive on the capsule and to the radiation and atomic modeling in the simulations.
Collapse
Affiliation(s)
- J J MacFarlane
- Prism Computational Sciences, Inc., 455 Science Drive, Suite 140, Madison, Wisconsin 53711, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Sinars DB, Bennett GR, Wenger DF, Cuneo ME, Porter JL. Evaluation of bent-crystal x-ray backlighting and microscopy techniques for the Sandia Z machine. APPLIED OPTICS 2003; 42:4059-4071. [PMID: 12868848 DOI: 10.1364/ao.42.004059] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
X-ray backlighting and microscopy systems for the 1-10-keV range based on spherically or toroidally bent crystals are discussed. These systems are ideal for use on the Sandia Z machine, a megajoule-class x-ray facility. Near-normal-incidence crystal microscopy systems have been shown to be more efficient than pinhole cameras with the same spatial resolution and magnification [Appl. Opt. 37, 1784 (1998)]. We show that high-resolution (< or = 10 microm) x-ray backlighting systems using bent crystals can be more efficient than analogous point-projection imaging systems. Examples of bent-crystal-backlighting results that demonstrate 10-microm resolution over a 20-mm field of view are presented.
Collapse
Affiliation(s)
- Daniel B Sinars
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185-1193, USA.
| | | | | | | | | |
Collapse
|