Wire, hybrid, and laser-cut X-pinches as Talbot-Lau backlighters for electron density diagnostics

Abstract Talbot-Lau X-ray Deflectometry (TXD) enables refraction-based imaging for high-energy-density physics (HEDP) experiments, and thus, it has been studied and developed with the goal of diagnosing plasmas relevant to Inertial Confinement and Magnetic Liner Inertial Fusion. X-pinches, known for reliably generating fast (~1 ns), small (~1 µm) x-ray sources, were driven on the compact current driver GenASIS (~200 kA, 150 ns) as a potential backlighter source for TXD. Considering that different X-pinch configurations have characteristic advantages and drawbacks as x-ray generating loads, three distinct copper X-pinch configurations were studied: the wire X-pinch, the hybrid X-pinch, and the laser-cut X-pinch. The Cu K-shell emission from each configuration was characterized and analyzed regarding the specific backlighter requirements for an 8 keV TXD system: spatial and temporal resolution, number of sources, time of emission, spectrum, and reproducibility. Recommendations for future experimental improvements and applications are presented. The electron density of static objects was retrieved from Moiré images obtained through TXD. This allowed to calculate the mass density of static samples within 4% of the expected value for laser-cut X-pinches, which were found to be the optimal X-pinch configuration for TXD due to their high reproducibility, small source size (≤5 µm), short duration (~1 ns FWHM), and up to 10^6 W peak power near 8 keV photon energy. Plasma loads were imaged through TXD for the first-time using laser-cut X-pinch backlighting. Experimental images were compared with simulations from the X-ray Wave-Front Propagation code, demonstrating that TXD can be a powerful x-ray refraction-based diagnostic for dense Z-pinch loads. Future plans for Talbot-Lau Interferometry diagnostics in the pulsed-power environment are described.

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Talbot-Lau x-ray deflectometer electron density diagnostic for laser and pulsed power high energy density plasma experiments (invited)

Review of Scientific Instruments ◽

10.1063/1.4959158 ◽

2016 ◽

Vol 87 (11) ◽

pp. 11D501 ◽

Cited By ~ 2

Author(s):

M. P. Valdivia ◽

D. Stutman ◽

C. Stoeckl ◽

C. Mileham ◽

I. A. Begishev ◽

...

Keyword(s):

Energy Density ◽

Electron Density ◽

High Energy ◽

Pulsed Power ◽

High Energy Density ◽

X Ray ◽

Density Plasma

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Publisher’s Note: “Talbot-Lau x-ray deflectometer electron density diagnostic for laser and pulsed power high energy density plasma experiments (invited)” [Rev. Sci. Instrum. 87, 11D501 (2016)]

Review of Scientific Instruments ◽

10.1063/1.4961297 ◽

2016 ◽

Vol 87 (11) ◽

pp. 11F901 ◽

Cited By ~ 2

Author(s):

M. P. Valdivia ◽

D. Stutman ◽

C. Stoeckl ◽

C. Mileham ◽

I. A. Begishev ◽

...

Keyword(s):

Energy Density ◽

Electron Density ◽

High Energy ◽

Pulsed Power ◽

High Energy Density ◽

X Ray ◽

Density Plasma

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X‐ray spectroscopy of high‐energy density inertial confinement fusion plasmas

Physics of Fluids B Plasma Physics ◽

10.1063/1.860964 ◽

1993 ◽

Vol 5 (9) ◽

pp. 3328-3336 ◽

Cited By ~ 61

Author(s):

C. J. Keane ◽

B. A. Hammel ◽

D. R. Kania ◽

J. D. Kilkenny ◽

R. W. Lee ◽

...

Keyword(s):

Energy Density ◽

Inertial Confinement Fusion ◽

High Energy ◽

High Energy Density ◽

Inertial Confinement ◽

Fusion Plasmas ◽

X Ray ◽

Confinement Fusion

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AWE experimental laser plasma program

Laser and Particle Beams ◽

10.1017/s0263034600182096 ◽

2000 ◽

Vol 18 (2) ◽

pp. 213-218 ◽

Cited By ~ 1

Author(s):

M. DUNNE ◽

J. EDWARDS ◽

P. GRAHAM ◽

A. EVANS ◽

S. ROTHMAN ◽

...

Keyword(s):

Equation Of State ◽

Inertial Confinement Fusion ◽

Fusion Energy ◽

Strong Shock ◽

High Energy ◽

High Energy Density ◽

Radiation Hydrodynamics ◽

Inertial Confinement ◽

X Ray ◽

Wide Range

The achievement of ignition from an Inertial Confinement Fusion capsule will require a detailed understanding of a wide range of high energy density phenomena. This paper presents some recent work aimed at improving our knowledge of the strength and equation of state characteristics of low-Z materials, and outlines data which will provide quantitative benchmarks against which our predictive radiation hydrodynamics capabilities can be tested. Improvements to our understanding in these areas are required if reproducible and predictable fusion energy production is to be achieved on the next generation of laser facilities.In particular, the HELEN laser at AWE has been used to create a thermal X-ray source with 140 eV peak radiation temperature and 3% instantaneous flux uniformity to allow measurements of the Equation of State of materials at pressures up to 20 Mbar to an accuracy of <±2% in shock velocity. The same laser has been used to investigate the onset of spallation upon the release of a strong shock at a metal-vacuum boundary, with dynamic radiography used to image the spalled material in flight for the first time. Finally, a range of experiments have been performed to generate quantitative radiation hydrodynamics data on the evolution of gross target defects, driven in both planar and imploding geometry. X-ray radiography was used to record the evolving target deformation in a system where the X-ray drive and unperturbed target response were sufficiently characterized to permit meaningful analysis. The results have been compared to preshot predictions made using a wide variety of fluid codes, highlighting substantial differences between the various approaches, and indicating significant discrepancies with the experimental reality. The techniques developed to allow quantitative comparisons are allowing the causes of the discrepancies to be identified, and are guiding the development of new simulation techniques.

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Talbot–Lau x-ray deflectometry phase-retrieval methods for electron density diagnostics in high-energy density experiments

Applied Optics ◽

10.1364/ao.57.000138 ◽

2018 ◽

Vol 57 (2) ◽

pp. 138 ◽

Cited By ~ 4

Author(s):

Maria Pia Valdivia ◽

Dan Stutman ◽

Christian Stoeckl ◽

Chad Mileham ◽

Ildar A. Begishev ◽

...

Keyword(s):

Energy Density ◽

Electron Density ◽

Phase Retrieval ◽

High Energy ◽

High Energy Density ◽

X Ray ◽

Density Diagnostics

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Structural evolution of high energy density V3+/V4+ mixed valent Na3V2O2x(PO4)2F3−2x (x = 0.8) sodium vanadium fluorophosphate using in situ synchrotron X-ray powder diffraction

Journal of Materials Chemistry A ◽

10.1039/c4ta00773e ◽

2014 ◽

Vol 2 (21) ◽

pp. 7766-7779 ◽

Cited By ~ 43

Author(s):

Paula Serras ◽

Verónica Palomares ◽

Teófilo Rojo ◽

Helen E. A. Brand ◽

Neeraj Sharma

Keyword(s):

Structural Evolution ◽

High Energy ◽

High Energy Density ◽

Sodium Ion Battery ◽

Time Resolved ◽

X Ray ◽

Xrd Study ◽

First Time ◽

Synchrotron Xrd

The first time-resolved in situ synchrotron XRD study of a cathode in a functioning sodium-ion battery. We determine the reaction mechanism, lattice parameters, sodium evolution, and the maximum sodium extraction for the fresh and precycled cell.

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Conceptual design of initial opacity experiments on the national ignition facility

Journal of Plasma Physics ◽

10.1017/s0022377816001173 ◽

2017 ◽

Vol 83 (1) ◽

Cited By ~ 11

Author(s):

R. F. Heeter ◽

J. E. Bailey ◽

R. S. Craxton ◽

B. G. DeVolder ◽

E. S. Dodd ◽

...

Keyword(s):

Inertial Confinement Fusion ◽

High Energy ◽

High Energy Density ◽

Inertial Confinement ◽

X Rays ◽

X Ray ◽

Confinement Fusion ◽

Final Design ◽

Laser Heated ◽

Point Projection

Accurate models of X-ray absorption and re-emission in partly stripped ions are necessary to calculate the structure of stars, the performance of hohlraums for inertial confinement fusion and many other systems in high-energy-density plasma physics. Despite theoretical progress, a persistent discrepancy exists with recent experiments at the Sandia Z facility studying iron in conditions characteristic of the solar radiative–convective transition region. The increased iron opacity measured at Z could help resolve a longstanding issue with the standard solar model, but requires a radical departure for opacity theory. To replicate the Z measurements, an opacity experiment has been designed for the National Facility (NIF). The design uses established techniques scaled to NIF. A laser-heated hohlraum will produce X-ray-heated uniform iron plasmas in local thermodynamic equilibrium (LTE) at temperatures ${\geqslant}150$ eV and electron densities ${\geqslant}7\times 10^{21}~\text{cm}^{-3}$. The iron will be probed using continuum X-rays emitted in a ${\sim}200$ ps, ${\sim}200~\unicode[STIX]{x03BC}\text{m}$ diameter source from a 2 mm diameter polystyrene (CH) capsule implosion. In this design, $2/3$ of the NIF beams deliver 500 kJ to the ${\sim}6$ mm diameter hohlraum, and the remaining $1/3$ directly drive the CH capsule with 200 kJ. Calculations indicate this capsule backlighter should outshine the iron sample, delivering a point-projection transmission opacity measurement to a time-integrated X-ray spectrometer viewing down the hohlraum axis. Preliminary experiments to develop the backlighter and hohlraum are underway, informing simulated measurements to guide the final design.

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