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At modern laser facilities, energy densities ranging from 1 Mbar to many hundreds of gigabars can regularly be achieved. These high-energy states of matter last for mere moments, measured in nanoseconds to tens of picoseconds, but during those times numerous high-precision instruments can be employed, revealing remarkable compressed matter physics, radiation–hydrodynamics physics, laser–matter interaction physics, and nuclear physics processes. We review the current progress of high-energy-density physics at the National Ignition Facility and describe the underlying physical principles.

An equation of state is a fundamental characteristic of a substance. It is necessary in numerous studies and practically important problems of high energy density physics. In this review, we consider the modern requirements to equations of state, theoretical and experimental methods used to study the thermodynamic properties of a substance, different aspects of constructing wide-range equations of state, and examples of application of wide-range equations of state in simulation of high-energy processes.

HIAF-BRing, a new multipurpose accelerator facility of the High Intensity heavy-ion Accelerator Facility project, requires an extremely high vacuum lower than 10 −11 mbar to fulfill the requirements of radioactive beam physics and high energy density physics. To achieve the required process pressure, the bench-marked codes of VAKTRAK and Molflow+ are used to simulate the pressure profiles of the BRing system. In order to ensure the accuracy of the implementation of VAKTRAK, the computational results are verified by measured pressure data and compared with a new simulation code BOLIDE on the current synchrotron CSRm. Since the verification of VAKTRAK has been done, the pressure profiles of the BRing are calculated with different parameters such as conductance, out-gassing rates and pumping speeds. According to the computational results, the optimal parameters are selected to achieve the required pressure for the BRing.

The birth of the closest naked-eye supernova in four centuries on 23 February 1987 had gone unnoticed until Ian Shelton discovered an extra star in the photographic plate he was developing early th...

International audience; A non-modal linear hydrodynamic stability analysis of ablation waves is carried out for the firsttime. This analysis is performed for unsteady self-similar solutions in slab symmetry of theEuler equations with nonlinear heat conduction, using a direct-adjoint method that results froma Lagrangian-based optimization problem. Such solutions are considered in connection withinertial confinement fusion (ICF) experiments where the hydrodynamic stability of ablativeflows has been identified as a key issue to the achievement of thermonuclear burn. Inherentlyunsteady, these flows are compressible, highly nonuniform with a steep heat front, and boundedby a material surface and a shock front — features that are possible sources of non-modalthermo-acoustics effects. Non-modal effects are presently exhibited on a particular ablation wavesolution. This finding raises the question of the existence and consequences of such effects inconfigurations of X-ray driven ablation that are more representative of ICF experiments, whichis the object of an ongoing investigation.

In order to understand the transport of fast electrons within solid density targets driven by an optical high power laser, wehave numerically investigated the dynamics and structure of strong self-generated magnetic fields in such experiments.Here we present a systematic study of the bulk magnetic field generation due to the ponderomotive current, Weibel-likeinstability and resistivity gradient between two solid layers. Using particle-in-cell simulations, we observe the effect ofvarying the laser and target parameters, including laser intensity, focal size, incident angle, preplasma scale length, targetthickness and material and experimental geometry. The simulation results suggest that the strongest magnetic field isgenerated with laser incident angles and preplasma scale lengths that maximize laser absorption efficiency. The recentcommissioning of experimental platforms equipped with both optical high power laser and X-ray free electron laser(XFEL), such as European XFEL-HED, LCLS-MEC and SACLA beamlines, provides unprecedented opportunities toprobe the self-generated bulk magnetic field by X-ray polarimetry via Faraday rotation with simultaneous high spatialand temporal resolution. We expect that this systematic numerical investigation will pave the way to design and optimizenear future experimental setups to probe the magnetic fields in such experimental platforms

The low-density polystyrene is often chosen as the converter material in high energy density physics experiments. The accurate thermodynamic and transport properties of polystyrene under extreme co...

This paper provides an overview of the frontier research fields and significant questions in nuclear physics regarding particle accelerators, and the status and future development trends for big-science facilities of particle accelerators are reviewed. Two Chinese government-approved “12th Five-Year” major science infrastructure facilities, the “High Intensity heavy-ion Accelerator Facility (HIAF)” and “China Initiative Accelerator Driven System (CiADS)”, are being constructed in Huizhou, Guangdong Province. Based on these two big-science projects (HIAF and CiADS), we proposed to establish a large-scale charged particle accelerator complex facility named the “Bright Electron and Ion research Facility (BEIF).” This facility will be dedicated to the research and development of nuclear physics and its interdisciplinary frontier fields. The research frontier fields of nuclear physics at the BEIF will include nuclear structure and astrophysics, nucleon structure, quark matter phase structure, and interdisciplinary fields between several significant frontiers of fundamental and nuclear physics, such as highly charged atomic physics and heavy ion-driven high energy density physics. BEIF will be a large-scale scientific complex facility comprising several superconducting ion LINAC accelerators, synchrotrons, storage rings, reactors, and various large experimental detectors and setups. BEIF will be built in three construction phases and will become one of the premier global large-scale particle accelerator complex facilities dedicated to the research of nuclear physics and technology.

The rapid development of a heavy-ion accelerator technology avails a new approach of producing high-energy-density (HED) matter in the laboratory, and an beneficial experimental platform for the inertial-confinement-fusion (ICF) that is driven by ion beams. The Institute of Modern Physics, Chinese Academy of Sciences, is responsible for the construction of the recently developed heavy ion accelerator facility (HIAF) in the 12th five-year plan period. The layout and building plan of the accelerator comlex regardinging HED and ICF inclusds the shooting of single-ion beams in phase-1, the shooting of double-ion beams in the optimization of phase-1 and the shooting of multi-ion beams in the phase-upgrade. A brief introduction of the state of matter driven by different beams-shooting methods and the new diagnostic development by IMP are presented. This paper will provide essential references of the experimental route and technical support for the research on ICF in China.

While major progress has been made in the research of inertial confinement fusion, significant challenges remain in the pursuit of ignition. To tackle the challenges, we propose a double-cone ignition (DCI) scheme, in which two head-on gold cones are used to confine deuterium–tritium (DT) shells imploded by high-power laser pulses. The scheme is composed of four progressive controllable processes: quasi-isentropic compression, acceleration, head-on collision and fast heating of the compressed fuel. The quasi-isentropic compression is performed inside two head-on cones. At the later stage of the compression, the DT shells in the cones are accelerated to forward velocities of hundreds of km s –1 . The head-on collision of the compressed and accelerated fuels from the cone tips transfer the forward kinetic energy to the thermal energy of the colliding fuel with an increased density. The preheated high-density fuel can keep its status for a period of approximately 200 ps. Within this period, MeV electrons generated by ps heating laser pulses, guided by a ns laser-produced strong magnetic field further heat the fuel efficiently. Our simulations show that the implosion inside the head-on cones can greatly mitigate the energy requirement for compression; the collision can preheat the compressed fuel of approximately 300 g cm −3 to a temperature above keV. The fuel can then reach an ignition temperature of greater than 5 keV with magnetically assisted heating of MeV electrons generated by the heating laser pulses. Experimental campaigns to demonstrate the scheme have already begun. This article is part of a discussion meeting issue ‘Prospects for high gain inertial fusion energy (part 1)’.

International audience; Material equation-of-state (EOS) models, generally providing the pressure and internal energy for a given density and temperature, are required to close the equations of hydrodynamics. As a result they are an essential piece of physics used to simulate inertial confinement fusion (ICF) implosions. Historically, EOS models based on different physical/chemical pictures of matter have been developed for ICF relevant materials such as the deuterium (D2) or deuterium-tritium (DT) fuel, as well as candidate ablator materials such as polystyrene (CH), glow-discharge polymer (GDP), beryllium (Be), carbon (C), and boron carbide (B4C). The accuracy of these EOS models can directly affect the reliability of ICF target design and understanding, as shock timing and material compressibility are essentially determined by what EOS models are used in ICF simulations. Systematic comparisons of current EOS models, benchmarking with experiments, not only help us to understand what the model differences are and why they occur, but also to identify the state-of-the-art EOS models for ICF target designers to use. For this purpose, the first Equation-of-State Workshop, supported by the US Department of Energy’s ICF program, was held at the Laboratory for Laser Energetics (LLE), University of Rochester on 31 May - 2nd June, 2017. This paper presents a detailed review on the findings from this workshop: (1) 5-10% model-model variations exist throughout the relevant parameter space, and can be much larger in regions where ionization and dissociation are occurring, (2) the D2 EOS is particularly uncertain, with no single model able to match the available experimental data, and this drives similar uncertainties in the CH EOS, and (3) new experimental capabilities such as Hugoniot measurements around 100 Mbar and high-quality temperature measurements are essential to reducing EOS uncertainty.

Sandia National Laboratories' origin began during World War II. In July 1945 our forerunner, Sandia Base, was established to develop, test, and assemble non-nuclear parts of weapons. Shock wave research became essential in the 1950s with the advent of supersonic and exoatmospheric missiles. A major concern was effects of radiation-produced shocks on materials. As a result, we developed a wide range of experimental, diagnostic, modeling, and computational capabilities. These have addressed complex issues related to both weapons and basic science. Notable applications have included analysis of the cause of the turret explosion aboard the USS Iowa and predicting the response to the Shoemaker- Levy comet impact on Jupiter. Six decades later, our research encompasses all aspects of material science from high energy density physics to low density plasma surface interactions.

Particle accelerators play a key role in a broad set of defense and security applications, including war-fighter and asset protection, cargo inspection, nonproliferation, materials characterization, and stockpile stewardship. Accelerators can replace the high activity radioactive sources that pose a security threat to developing a radiological dispersal device, and, can be used to produce isotopes for medical, industrial, and research purposes. An overview of current and emerging accelerator technologies relevant to addressing the needs of defense and security is presented.

The Super Proton Synchrotron (SPS) will serve as an injector to the Large Hadron Collider (LHC) at CERN as well as it is used to accelerate and extract proton beams for fixed target experiments. In either case, safety of operation is a very important issue that needs to be carefully addressed. This paper presents detailed numerical simulations of the thermodynamic and hydrodynamic response of solid targets made of copper and tungsten that experience impact of a full SPS beam comprized of 288 bunches of 450 GeV/c protons. These simulations have shown that the material will be seriously damaged if such an accident happens. An interesting outcome of this work is that the SPS can be used to carry out dedicated experiments to study High Energy Density (HED) states in matter.

International audience; The creation of high energy density plasma states produced during laser-solid interaction on a sub-picosecond timescale opens a way to create astrophysical plasmas in the lab to investigate their properties, such as the frequency-dependent refractive index. Available probes to measure absorption and phase-changes given by the complex refractive index of the plasma state are extreme-UV (EUV) and soft X-ray (XUV) ultra-short pulses from high harmonic generation (HHG). For demanding imaging applications such as single-shot measurements of solid density plasmas, the HHG probe has to be optimized in photon number and characterized in intensity and wavefront stability from shot-to-shot. In an experiment, a coherent EUV source based on HHG driven by a compact diode-pumped laser is optimized in photons per pulse for argon and xenon, and the shot-to-shot intensity stability and wavefront changes are characterized. The experimental results are compared to an analytical model estimating the HHG yield, showing good agreement. The obtained values are compared to available data for solid density plasmas to confirm the feasibility of HHG as a probe.

International audience; A number of laser facilities coming online all over the world promise the capability of high-power laser experiments with shot repetition rates between 1 and 10 Hz. Target availability and technical issues related to the interaction environment could become a bottleneck for the exploitation of such facilities. In this paper, we report on target needs for three different classes of experiments: dynamic compression physics, electron transport and isochoric heating, and laser-driven particle and radiation sources. We also review some of the most challenging issues in target fabrication and high repetition rate operation. Finally, we discuss current target supply strategies and future perspectives to establish a sustainable target provision infrastructure for advanced laser facilities.

International audience

A model is presented to calculate the stopping power of ions propagating in dense matter. Comparisons with experiment in the cold dense regime are presented and discussed. Further, we present results from the warm dense matter regime and the field of high energy density physics.

With the rapid developing of high energy lasers and ultrashort high intensity lasers, high energy density conditions, which widely exist in astronomical environment and nuclear explosion, can be created in laboratories. This provides new opportunities for various physics fields and forms new interdisciplinary frontiers. In this review, recent studies of astronomic phenomena in a controllable way in laboratories with high power lasers will be first presented. Then prospects of the new physics driven by next generation ultra-relativistic lasers will be discussed.

High Energy Density (HED) physics spans over numerous areas of basic and applied physics, for example, astrophysics, planetary physics, geophysics, inertial fusion and many others. Due to this reason, it has been a subject of very active research over the past many decades. Static as well as dynamic methods have been applied to generate samples of HED matter in the laboratory. The most commonly used tool in the static techniques is the diamond anvil cell while the dynamic methods involve shock compression of matter. During the past fifteen years, great progress has been made on the development of bunched intense particle beams that have emerged as an additional new tool for studying HED physics. In this paper we present two experiment designs that have been worked out for HED physics studies at the Facility for Antiprotons and Ion Research (FAIR) at Darmstadt. This facility has entered into construction phase and will provide one of the largest and most powerful particle accelerators in the world. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A high-temperature (>340 eV) half-hohlraum target platform has been developed on the National Ignition Facility (NIF) to enable the study of diffusive supersonic radiation flow in low-density foams...

Since the 1970s, high energy heavy ion accelerators have been one of the leading options for imploding and igniting targets for inertial fusion energy production. Following the energy crisis of the early 1970s, a number of people in the international accelerator community enthusiastically began working on accelerators for this application. In the last decade, there has also been significant interest in using accelerators to study high energy density physics (HEDP). Nevertheless, research on heavy ion accelerators for fusion has proceeded slowly pending demonstration of target ignition using the National Ignition Facility (NIF), a laser-based facility at Lawrence Livermore National Laboratory. A recent report of the National Research Council recommends expansion of accelerator research in the US if and when the NIF achieves ignition. Fusion target physics and the economics of commercial energy production place constraints on the design of accelerators for fusion applications. From a scientific standpoint, phase space and space charge considerations lead to the most stringent constraints. Meeting these constraints almost certainly requires the use of multiple beams of heavy ions with kinetic energies >1 GeV. These constraints also favor the use of singly charged ions. This article discusses the constraints for both fusion and HEDP, and explains how they lead to the requirements on beam parameters. RF and induction linacs are currently the leading contenders for fusion applications. We discuss the advantages and disadvantages of both options. We also discuss the principal issues that must yet be resolved.

The Z-Backlighter Laser Facility at Sandia National Laboratories was developed to enable high energy density physics experiments in conjunction with the Z Pulsed Power Facility at Sandia National Laboratories, with an emphasis on backlighting. Since the first laser system there became operational in 2001, the facility has continually evolved to add new capability and new missions. The facility currently has several high energy laser systems including the nanosecond/multi-kilojoule Z-Beamlet Laser (ZBL), the sub-picosecond/kilojoule- class Z-Petawatt (ZPW) Laser, and the smaller nanosecond/100 J-class Chaco laser. In addition to these, the backlighting mission requires a regular stream of coated consumable optics such as debris shields and vacuum windows, which led to the development of the Sandia Optics Support Facility to support the unique high damage threshold optical coating needs described.

The Los Alamos Inertial Confinement Fusion and Science Programs engage in a vigorous array of experiments, theory, and modeling. We use the three major High Energy Density facilities, NIF, Omega, and Z to perform experiments. These include opacity, radiation transport, hydrodynamics, ignition science, and burn experiments to aid the ICF and Science campaigns in reaching their stewardship goals. The ICF program operates two nuclear diagnostics at NIF, the neutron imaging system and the gamma reaction history instruments. Both systems are being expanded with significant capability enhancements.

In this chapter we consider a nuclear explosion as a unique multistage physical phenomenon whose study is of interest to scientists of different realms of knowledge, particularly to experts in high energy density physics. In the first and second sections of this chapter we will study the former stage—the initiation of a nuclear explosion. The last section of the chapter is dedicated to experiments in the generation and study of extreme states of matter with the use of intense shock waves driven by a nuclear explosion.

The rapid progress of laser technology has opened up the possibility of generating ultrashort laser pulses of the nano–pico–femto1–atto–second range and of bringing (see Tables 3.2, 3.3; Fig. 3.2) the existing and projected laser complexes into the petawatt–zettawatt power range (Figs 4.1, 4.2), making it possible to span a wide range of power densities up to the highest values achievable today, q ≈ 1022– 1023 W/cm2 [70, 69, 6, 14], which will undoubtedly rise with time.

The National Ignition Facility (NIF) is a high-energy laser facility comprised of 192 beamlines that house thousands of optics. These optics guide, amplify and tightly focus light onto a tiny target for fusion ignition research and high energy density physics experiments. The condition of these optics is key to the economic, efficient and maximally energetic performance of the laser. Our goal, and novel achievement, is to find on the optics any imperfections while they are tens of microns in size, track them through time to see if they grow and if so, remove the optic and repair the single site so the entire optic can then be re-installed for further use on the laser. This paper gives an overview of the image analysis used for detecting, measuring, and tracking sites of interest on an optic while it is installed on the beamline via in situ inspection and after it has been removed for maintenance. In this way, the condition of each optic is monitored throughout the optic's lifetime. This overview paper will summarize key algorithms and technical developments for custom image analysis and processing and highlight recent improvements. (Associated papers will include more details on these issues.) We will also discuss the use of OI Analysis for daily operation of the NIF laser and its extension to inspection of NIF targets.