scholarly journals Conceptual design of initial opacity experiments on the national ignition facility

2017 ◽  
Vol 83 (1) ◽  
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.

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

1993 ◽  
Vol 5 (9) ◽  
pp. 3328-3336 ◽  
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

scholarly journals AWE experimental laser plasma program

2000 ◽  
Vol 18 (2) ◽  
pp. 213-218 ◽  
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.

scholarly journals High energy electron radiography scheme with high spatial and temporal resolution in three dimension based on a e-LINAC

2016 ◽  
Vol 34 (2) ◽  
pp. 338-342 ◽  
Author(s):  
Y. Zhao ◽  
Z. Zhang ◽  
W. Gai ◽  
Y. Du ◽  
S. Cao ◽  
...  
Keyword(s):  
Electron Beam ◽  
Temporal Resolution ◽  
Inertial Confinement Fusion ◽  
High Energy ◽  
High Energy Density ◽  
Inertial Confinement ◽  
Three Dimension ◽  
Scattered Electron ◽  
Electron Linear Accelerator ◽  
Confinement Fusion

AbstractWe present a scheme of electron beam radiography to dynamically diagnose the high energy density (HED) matter in three orthogonal directions simultaneously based on electron Linear Accelerator. The dynamic target information such as, its profile and density could be obtained through imaging the scattered electron beam passing through the target. Using an electron bunch train with flexible time structure, a very high temporal evolution could be achieved. In this proposed scheme, it is possible to obtain 1010 frames/second in one experimental event, and the temporal resolution can go up to 1 ps, spatial resolution to 1 µm. Successful demonstration of this concept will have a major impact for both future inertial confinement fusion science and HED physics research.

scholarly journals High energy x-ray imager for inertial confinement fusion at the National Ignition Facility

2006 ◽  
Vol 77 (10) ◽  
pp. 10E301 ◽  
Author(s):  
Riccardo Tommasini ◽  
Jeffrey A. Koch ◽  
Bruce Young ◽  
Ed Ng ◽  
Tom Phillips ◽  
...  
Keyword(s):  
Inertial Confinement Fusion ◽  
High Energy ◽  
Inertial Confinement ◽  
National Ignition Facility ◽  
X Ray ◽  
Confinement Fusion

scholarly journals Inertial confinement fusion: a defence context

2020 ◽  
Vol 378 (2184) ◽  
pp. 20200012 ◽  
Author(s):  
Andrew Randewich ◽  
Rob Lock ◽  
Warren Garbett ◽  
Dominic Bethencourt-Smith
Keyword(s):  
Inertial Confinement Fusion ◽  
High Performance ◽  
Fusion Energy ◽  
High Gain ◽  
High Energy ◽  
High Energy Density ◽  
Inertial Confinement ◽  
Science And Engineering ◽  
Confinement Fusion ◽  
The Uk

Almost 30 years since the last UK nuclear test, it remains necessary regularly to underwrite the safety and effectiveness of the National Nuclear Deterrent. To do so has been possible to date because of the development of continually improving science and engineering tools running on ever more powerful high-performance computing platforms, underpinned by cutting-edge experimental facilities. While some of these facilities, such as the Orion laser, are based in the UK, others are accessed by international collaboration. This is most notably with the USA via capabilities such as the National Ignition Facility, but also with France where a joint hydrodynamics facility is nearing completion following establishment of a Treaty in 2010. Despite the remarkable capability of the science and engineering tools, there is an increasing requirement for experiments as materials age and systems inevitably evolve further from what was specifically trialled at underground nuclear tests (UGTs). The data from UGTs will remain the best possible representation of the extreme conditions generated in a nuclear explosion, but it is essential to supplement these data by realizing new capabilities that will bring us closer to achieving laboratory simulations of these conditions. For high-energy-density physics, the most promising technique for generating temperatures and densities of interest is inertial confinement fusion (ICF). Continued research in ICF by the UK will support the certification of the deterrent for decades to come; hence the UK works closely with the international community to develop ICF science. UK Ministry of Defence © Crown Owned Copyright 2020/AWE. This article is part of a discussion meeting issue ‘Prospects for high gain inertial fusion energy (part 1)'.

Sign in / Sign up

Export Citation Format

Share Document