1
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Huang Y, Liang Z, Zeng J, Yuan J. Nonideal effects on ionization potential depression and ionization balance in dense Al and Au plasmas. Phys Rev E 2024; 109:045210. [PMID: 38755935 DOI: 10.1103/physreve.109.045210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Accepted: 04/04/2024] [Indexed: 05/18/2024]
Abstract
For low-density plasmas, the ionization balance can be properly described by the normal Saha equation in the chemical picture. For dense plasmas, however, nonideal effects due to the interactions between the electrons and ions and among the electrons themselves affect the ionization potential depression and the ionization balance. With the increasing of plasma density, the pressure ionization starts to play a more obvious role and competes with the thermal ionization. Based on a local-density temperature-dependent ion-sphere model, we develop a unified and self-consistent theoretical formalism to simultaneously investigate the ionization potential depression, the ionization balance, and the charge states distributions of the dense plasmas. In this work, we choose Al and Au plasmas as examples as Al is a prototype light element and Au is an important heavy element in many research fields such as in the inertial confinement fusion. The nonideal effect of the free electrons in the plasmas is considered by the single-electron effective potential contributed by both the bound electrons of different charge states and the free electrons in the plasmas. For the Al plasmas, we can reconcile the results of two experiments on measuring the ionization potential depression, in which one experiment can be better explained by the Stewart-Pyatt model while the other fits better with the Ecker-Kröll model. For dense Au plasmas, the results show that the double peak structure of the charge state distribution appears to be a common phenomenon. In particular, the calculated ionization balance shows that the two- and three-peak structures can appear simultaneously for denser Au plasmas above ∼30g/cm^{3}.
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Affiliation(s)
- Yihua Huang
- College of Science, Zhejiang University of Technology, Hangzhou Zhejiang 310023, People's Republic of China
| | - Zhenhao Liang
- College of Science, Zhejiang University of Technology, Hangzhou Zhejiang 310023, People's Republic of China
| | - Jiaolong Zeng
- College of Science, Zhejiang University of Technology, Hangzhou Zhejiang 310023, People's Republic of China
| | - Jianmin Yuan
- Institute of Atomic and Molecular Physics, Jilin University, Changchun Jilin 130012, People's Republic of China
- Graduate School of China Academy of Engineering Physics, Beijing 100193, People's Republic of China
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2
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Moldabekov Z, Schwalbe S, Böhme MP, Vorberger J, Shao X, Pavanello M, Graziani FR, Dornheim T. Bound-State Breaking and the Importance of Thermal Exchange-Correlation Effects in Warm Dense Hydrogen. J Chem Theory Comput 2024; 20:68-78. [PMID: 38133546 PMCID: PMC10782774 DOI: 10.1021/acs.jctc.3c00934] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 12/01/2023] [Accepted: 12/01/2023] [Indexed: 12/23/2023]
Abstract
Hydrogen at extreme temperatures and pressures is of key relevance for cutting-edge technological applications, with inertial confinement fusion research being a prime example. In addition, it is ubiquitous throughout our universe and naturally occurs in a variety of astrophysical objects. In the present work, we present exact ab initio path integral Monte Carlo (PIMC) results for the electronic density of warm dense hydrogen along a line of constant degeneracy across a broad range of densities. Using the well-known concept of reduced density gradients, we develop a new framework to identify the breaking of bound states due to pressure ionization in bulk hydrogen. Moreover, we use our PIMC results as a reference to rigorously assess the accuracy of a variety of exchange-correlation (XC) functionals in density functional theory calculations for different density regions. Here, a key finding is the importance of thermal XC effects for the accurate description of density gradients in high-energy-density systems. Our exact PIMC test set is freely available online and can be used to guide the development of new methodologies for the simulation of warm dense matter and beyond.
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Affiliation(s)
- Zhandos Moldabekov
- Center
for Advanced Systems Understanding (CASUS), Görlitz D-02826, Germany
- Helmholtz-Zentrum
Dresden-Rossendorf (HZDR), Dresden D-01328, Germany
| | - Sebastian Schwalbe
- Center
for Advanced Systems Understanding (CASUS), Görlitz D-02826, Germany
- Helmholtz-Zentrum
Dresden-Rossendorf (HZDR), Dresden D-01328, Germany
| | | | - Jan Vorberger
- Helmholtz-Zentrum
Dresden-Rossendorf (HZDR), Dresden D-01328, Germany
| | - Xuecheng Shao
- Department
of Chemistry, Rutgers University, Newark, New Jersey 07102, United States
- Department
of Physics, Rutgers University, Newark, New Jersey 07102, United States
| | - Michele Pavanello
- Department
of Chemistry, Rutgers University, Newark, New Jersey 07102, United States
- Department
of Physics, Rutgers University, Newark, New Jersey 07102, United States
| | - Frank R. Graziani
- Lawrence
Livermore National Laboratory (LLNL), Livermore 94550, California, United States
| | - Tobias Dornheim
- Center
for Advanced Systems Understanding (CASUS), Görlitz D-02826, Germany
- Helmholtz-Zentrum
Dresden-Rossendorf (HZDR), Dresden D-01328, Germany
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3
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Gawne T, Campbell T, Forte A, Hollebon P, Perez-Callejo G, Humphries OS, Karnbach O, Kasim MF, Preston TR, Lee HJ, Miscampbell A, van den Berg QY, Nagler B, Ren S, Royle RB, Wark JS, Vinko SM. Investigating mechanisms of state localization in highly ionized dense plasmas. Phys Rev E 2023; 108:035210. [PMID: 37849197 DOI: 10.1103/physreve.108.035210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 08/11/2023] [Indexed: 10/19/2023]
Abstract
We present experimental observations of K_{β} emission from highly charged Mg ions at solid density, driven by intense x rays from a free electron laser. The presence of K_{β} emission indicates the n=3 atomic shell is relocalized for high charge states, providing an upper constraint on the depression of the ionization potential. We explore the process of state relocalization in dense plasmas from first principles using finite-temperature density functional theory alongside a wave-function localization metric, and find excellent agreement with experimental results.
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Affiliation(s)
- Thomas Gawne
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - Thomas Campbell
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - Alessandro Forte
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - Patrick Hollebon
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - Gabriel Perez-Callejo
- Departamento de Física Teórica, Atómica y Óptica, Universidad de Valladolid, Valladolid, Spain
| | | | - Oliver Karnbach
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - Muhammad F Kasim
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | | | - Hae Ja Lee
- SLAC National Accelerator Laboratory, 2575 Sand Hill Rd, Menlo Park, California 94025, USA
| | - Alan Miscampbell
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - Quincy Y van den Berg
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - Bob Nagler
- SLAC National Accelerator Laboratory, 2575 Sand Hill Rd, Menlo Park, California 94025, USA
| | - Shenyuan Ren
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - Ryan B Royle
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - Justin S Wark
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - Sam M Vinko
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
- Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot OX11 0QX, United Kingdom
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4
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Karasiev VV, Hu SX, Shaffer NR, Miloshevsky G. First-principles study of L-shell iron and chromium opacity at stellar interior temperatures. Phys Rev E 2022; 106:065202. [PMID: 36671100 DOI: 10.1103/physreve.106.065202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 11/23/2022] [Indexed: 06/17/2023]
Abstract
Recently developed free-energy density functional theory (DFT)-based methodology for optical property calculations of warm dense matter has been applied for studying L-shell opacity of iron and chromium at T=182 eV. We use Mermin-Kohn-Sham density functional theory with a ground-state and a fully-temperature-dependent generalized gradient approximation exchange-correlation (XC) functionals. It is demonstrated that the role of XC at such a high-T is negligible due to the total free energy of interacting systems being dominated by the noninteracting free-energy term, in agreement with estimations for the homogeneous electron gas. Our DFT predictions are compared with the radiative emissivity and opacity of the dense plasma model, with the real-space Green's function method, and with experimental measurements. Good agreement is found between all three theoretical methods, and in the bound-continuum region for Cr when compared with the experiment, while the discrepancy between direct DFT calculations and the experiment for Fe remains essentially the same as for plasma-physics models.
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Affiliation(s)
- Valentin V Karasiev
- Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623, USA
| | - S X Hu
- Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623, USA
| | - Nathaniel R Shaffer
- Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623, USA
| | - Gennady Miloshevsky
- Department of Mechanical and Nuclear Engineering, Virginia Commonwealth University, Richmond, Virginia 23284, USA
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5
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Hu SX, Bishel DT, Chin DA, Nilson PM, Karasiev VV, Golovkin IE, Gu M, Hansen SB, Mihaylov DI, Shaffer NR, Zhang S, Walton T. Probing atomic physics at ultrahigh pressure using laser-driven implosions. Nat Commun 2022; 13:6780. [PMID: 36384992 PMCID: PMC9668816 DOI: 10.1038/s41467-022-34618-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 10/31/2022] [Indexed: 11/17/2022] Open
Abstract
Spectroscopic measurements of dense plasmas at billions of atmospheres provide tests to our fundamental understanding of how matter behaves at extreme conditions. Developing reliable atomic physics models at these conditions, benchmarked by experimental data, is crucial to an improved understanding of radiation transport in both stars and inertial fusion targets. However, detailed spectroscopic measurements at these conditions are rare, and traditional collisional-radiative equilibrium models, based on isolated-atom calculations and ad hoc continuum lowering models, have proved questionable at and beyond solid density. Here we report time-integrated and time-resolved x-ray spectroscopy measurements at several billion atmospheres using laser-driven implosions of Cu-doped targets. We use the imploding shell and its hot core at stagnation to probe the spectral changes of Cu-doped witness layer. These measurements indicate the necessity and viability of modeling dense plasmas with self-consistent methods like density-functional theory, which impact the accuracy of radiation transport simulations used to describe stellar evolution and the design of inertial fusion targets. Atoms and molecules under extreme temperature and pressure can be investigated using dense plasmas achieved by laser-driven implosion. Here the authors report spectral change of copper in billions atmosphere pressure that can only be explained by a self-consistent approach.
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6
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Zhang S, Karasiev VV, Shaffer N, Mihaylov DI, Nichols K, Paul R, Goshadze RMN, Ghosh M, Hinz J, Epstein R, Goedecker S, Hu SX. First-principles equation of state of CHON resin for inertial confinement fusion applications. Phys Rev E 2022; 106:045207. [PMID: 36397594 DOI: 10.1103/physreve.106.045207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 09/24/2022] [Indexed: 06/16/2023]
Abstract
A wide-range (0 to 1044.0 g/cm^{3} and 0 to 10^{9} K) equation-of-state (EOS) table for a CH_{1.72}O_{0.37}N_{0.086} quaternary compound has been constructed based on density-functional theory (DFT) molecular-dynamics (MD) calculations using a combination of Kohn-Sham DFT MD, orbital-free DFT MD, and numerical extrapolation. The first-principles EOS data are compared with predictions of simple models, including the fully ionized ideal gas and the Fermi-degenerate electron gas models, to chart their temperature-density conditions of applicability. The shock Hugoniot, thermodynamic properties, and bulk sound velocities are predicted based on the EOS table and compared to those of C-H compounds. The Hugoniot results show the maximum compression ratio of the C-H-O-N resin is larger than that of CH polystyrene due to the existence of oxygen and nitrogen; while the other properties are similar between CHON and CH. Radiation hydrodynamic simulations have been performed using the table for inertial confinement fusion targets with a CHON ablator and compared with a similar design with CH. The simulations show CHON outperforms CH as the ablator for laser-direct-drive target designs.
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Affiliation(s)
- Shuai Zhang
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - Valentin V Karasiev
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - Nathaniel Shaffer
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - Deyan I Mihaylov
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - Katarina Nichols
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - Reetam Paul
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - R M N Goshadze
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - Maitrayee Ghosh
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - Joshua Hinz
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - Reuben Epstein
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - Stefan Goedecker
- Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland
| | - S X Hu
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
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7
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Multi-Configuration Calculation of Ionization Potential Depression. PLASMA 2022. [DOI: 10.3390/plasma5040029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The modelling of ionization potential depression in warm and hot dense plasmas constitutes a real theoretical challenge due to ionic coupling and electron degeneracy effects. In this work, we present a quantum statistical model based on a multi-configuration description of the electronic structure in the framework of Density Functional Theory. We discuss different conceptual issues inherent to the definition of ionization potential depression and compare our results with the famous and widely-used Ecker-Kröll and Stewart-Pyatt models.
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8
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Jin R, Jurek Z, Santra R, Son SK. Plasma environmental effects in the atomic structure for simulating x-ray free-electron-laser-heated solid-density matter. Phys Rev E 2022; 106:015206. [PMID: 35974549 DOI: 10.1103/physreve.106.015206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 07/08/2022] [Indexed: 06/15/2023]
Abstract
High energy density (HED) matter exists extensively in the Universe, and it can be created with extreme conditions in laboratory facilities such as x-ray free-electron lasers (XFEL). In HED matter, the electronic structure of individual atomic ions is influenced by a dense plasma environment, and one of the most significant phenomena is the ionization potential depression (IPD). Incorporation of the IPD effects is of great importance in accurate modeling of dense plasmas. All theoretical treatments of IPD so far have been based on the assumption of local thermodynamic equilibrium, but its validity is questionable in ultrafast formation dynamics of dense plasmas, particularly when interacting with intense XFEL pulses. A treatment of transient IPD, based on an electronic-structure calculation of an atom in the presence of a plasma environment described by classical particles, has recently been proposed [Phys. Rev. E 103, 023203 (2021)2470-004510.1103/PhysRevE.103.023203], but its application to and impact on plasma dynamics simulations have not been investigated yet. In this work, we extend XMDYN, a hybrid quantum-classical approach combining Monte Carlo and molecular dynamics, by incorporating the proposed IPD treatment into plasma dynamics simulations. We demonstrate the importance of the IPD effects in theoretical modeling of aluminum dense plasmas by comparing two XMDYN simulations: one with electronic-structure calculations of isolated atoms (without IPD) and the other with those of atoms embedded in a plasma (with IPD). At equilibrium, the mean charge obtained in the plasma simulation with IPD is in good agreement with the full quantum-mechanical average-atom model. The present approach promises to be a reliable tool to simulate the creation and nonequilibrium evolution of dense plasmas induced by ultraintense and ultrashort XFEL pulses.
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Affiliation(s)
- Rui Jin
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Zoltan Jurek
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Robin Santra
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
- Department of Physics, Universität Hamburg, Notkestrasse 9-11, 22607 Hamburg, Germany
| | - Sang-Kil Son
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
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9
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Zeng J, Ye C, Liu P, Gao C, Li Y, Yuan J. The Strong Enhancement of Electron-Impact Ionization Processes in Dense Plasma by Transient Spatial Localization. Int J Mol Sci 2022; 23:ijms23116033. [PMID: 35682711 PMCID: PMC9181145 DOI: 10.3390/ijms23116033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 05/24/2022] [Accepted: 05/25/2022] [Indexed: 02/01/2023] Open
Abstract
Recent experiments have observed much higher electron–ion collisional ionization cross sections and rates in dense plasmas than predicted by the current standard atomic collision theory, including the plasma screening effect. We suggest that the use of (distorted) plane waves for incident and scattered electrons is not adequate to describe the dissipation that occurs during the ionization event. Random collisions with free electrons and ions in plasma cause electron matter waves to lose their phase, which results in the partial decoherence of incident and scattered electrons. Such a plasma-induced transient spatial localization of the continuum electron states significantly modifies the wave functions of continuum electrons, resulting in a strong enhancement of the electron–ion collisional ionization of ions in plasma compared to isolated ions. Here, we develop a theoretical formulation to calculate the differential and integral cross sections by incorporating the effects of plasma screening and transient spatial localization. The approach is then used to investigate the electron-impact ionization of ions in solid-density magnesium plasma, yielding results that are consistent with experiments. In dense plasma, the correlation of continuum electron energies is modified, and the integral cross sections and rates increase considerably. For the ionization of Mg9+e+1s22s2S→1s21S+2e, the ionization cross sections increase several-fold, and the rates increase by one order of magnitude. Our findings provide new insight into collisional ionization and three-body recombination and may aid investigations of the transport properties and nonequilibrium evolution of dense plasma.
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Affiliation(s)
- Jiaolong Zeng
- College of Science, Zhejiang University of Technology, Hangzhou 310023, China
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, China; (C.Y.); (P.L.); (C.G.); (Y.L.)
- Correspondence: (J.Z.); (J.Y.)
| | - Chen Ye
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, China; (C.Y.); (P.L.); (C.G.); (Y.L.)
| | - Pengfei Liu
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, China; (C.Y.); (P.L.); (C.G.); (Y.L.)
| | - Cheng Gao
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, China; (C.Y.); (P.L.); (C.G.); (Y.L.)
| | - Yongjun Li
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, China; (C.Y.); (P.L.); (C.G.); (Y.L.)
| | - Jianmin Yuan
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, China; (C.Y.); (P.L.); (C.G.); (Y.L.)
- Graduate School of China Academy of Engineering Physics, Beijing 100193, China
- Correspondence: (J.Z.); (J.Y.)
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10
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Shaffer NR, Starrett CE. Dense plasma opacity via the multiple-scattering method. Phys Rev E 2022; 105:015203. [PMID: 35193239 DOI: 10.1103/physreve.105.015203] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 12/20/2021] [Indexed: 11/07/2022]
Abstract
The calculation of the optical properties of hot dense plasmas with a model that has self-consistent plasma physics is a grand challenge for high energy density science. Here we exploit a recently developed electronic structure model that uses multiple scattering theory to solve the Kohn-Sham density functional theory equations for dense plasmas. We calculate opacities in this regime, validate the method, and apply it to recent experimental measurements of opacity for Cr, Ni, and Fe. Good agreement is found in the quasicontinuum region for Cr and Ni, while the self-consistent plasma physics of the approach cannot explain the observed difference between models and the experiment for Fe.
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Affiliation(s)
- Nathaniel R Shaffer
- Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545, USA and Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623, USA
| | - Charles E Starrett
- Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545, USA
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11
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Zan X, Lin C, Hou Y, Yuan J. Local field correction to ionization potential depression of ions in warm or hot dense matter. Phys Rev E 2021; 104:025203. [PMID: 34525605 DOI: 10.1103/physreve.104.025203] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 07/19/2021] [Indexed: 11/07/2022]
Abstract
An analytical self-consistent approach was recently established to predict the ionization potential depression (IPD) in multicomponent dense plasmas, which is achieved by considering the self-energy of ions and electrons within the quantum statistical theory. In order to explicitly account for the exchange-correlation effect of electrons, we incorporate the effective static approximation of local field correction (LFC) within our IPD framework through the connection of dynamical structure factor. The effective static approximation poses an accurate description for the asymptotic large wave number behavior with the recently developed machine learning representation of static LFC induced from the path-integral Monte Carlo data. Our calculation shows that the introduction of static LFC through dynamical structure factor brings a nontrivial influence on IPD at warm/hot dense matter conditions. The correlation effect within static LFC could provide up to 20% correction to free-electron contribution of IPD in the strong coupling and degeneracy regime. Furthermore, a new screening factor is obtained from the density distribution of free electrons calculated within the average-atom model, with which excellent agreements are observed with other methods and experiments at warm/hot dense matter conditions.
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Affiliation(s)
- Xiaolei Zan
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha, Hunan 410073, People's Republic of China
| | - Chengliang Lin
- Graduate School of China Academy of Engineering Physics, Beijing 100193, People's Republic of China
| | - Yong Hou
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha, Hunan 410073, People's Republic of China
| | - Jianmin Yuan
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha, Hunan 410073, People's Republic of China.,Graduate School of China Academy of Engineering Physics, Beijing 100193, People's Republic of China
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12
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Zhang P, Jin Y, Zan X, Liu P, Li Y, Gao C, Hou Y, Zeng J, Yuan J. Enhancement of electron-impact ionization induced by warm dense environments. Phys Rev E 2021; 104:035204. [PMID: 34654195 DOI: 10.1103/physreve.104.035204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 08/27/2021] [Indexed: 06/13/2023]
Abstract
Studies have shown significant discrepancies between the recent experiment [Berg et al., Phys. Rev. Lett. 120, 055002 (2018)PRLTAO10.1103/PhysRevLett.120.055002] and current theoretical calculations on the electron-impact ionization cross section of ions in warm dense magnesium. Here, we present a systematic study the effects of the ionic correlations and free-electron screening on the electron-impact ionization of ions in warm dense matter. The ionic correlation and the free-electron screening effects yield additional Hermitian terms to the calculation of the ionic central-force-field potential, which significantly change the electronic structure compared with that of the isolated ion. In calculating the electron-impact ionization, we describe the impact and ionized electrons using a damped-distorted wave function, which considers the momentum relaxation of free electrons due to collisions with other free electrons and ions. We reproduce the electron-impact ionization process for Mg^{7+} in the solid-density plasma and increase the ionization cross section by one order of magnitude compared with that of the isolated ion, which excellently agrees with the experimental result of Berg et al.
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Affiliation(s)
- Ping Zhang
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
| | - Yang Jin
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
| | - Xiaolei Zan
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
| | - Pengfei Liu
- College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
| | - Yongjun Li
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
| | - Cheng Gao
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
| | - Yong Hou
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
| | - Jiaolong Zeng
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
- College of Science, Zhejiang University of Technology, Hangzhou Zhejiang 310023, People's Republic of China
| | - Jianmin Yuan
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
- Graduate School, China Academy of Engineering Physics, Beijing 100193, People's Republic of China
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13
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Karasiev VV, Hu SX. Unraveling the intrinsic atomic physics behind x-ray absorption line shifts in warm dense silicon plasmas. Phys Rev E 2021; 103:033202. [PMID: 33862735 DOI: 10.1103/physreve.103.033202] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 02/12/2021] [Indexed: 11/07/2022]
Abstract
We present a free-energy density functional theory (DFT)-based methodology for optical property calculations of warm dense matter to cover a wide range of thermodynamic conditions and photon energies including the entire x-ray range. It uses Mermin-Kohn-Sham density functional theory with exchange-correlation (XC) thermal effects taken into account via a fully temperature dependent generalized gradient approximation XC functional. The methodology incorporates a combination of the ab initio molecular dynamics (AIMD) snapshotted Kubo-Greenwood optic data with a single atom in simulation cell calculations to close the photon energy gap between the L and K edges and extend the K-edge tail toward many-keV photon energies. This gap arises in the standard scheme due to a prohibitively large number of bands required for the Kubo-Greenwood calculations with AIMD snapshots. Kubo-Greenwood data on snapshots provide an accurate description of optic properties at low photon frequencies slightly beyond the L edge and x-ray absorption near edges structure (XANES) spectra, while data from periodic calculations with single atoms cover the tail regions beyond the edges. To demonstrate its applicability to mid-Z materials where the standard DFT-based approach is not computationally feasible, we have applied it to opacity calculations of warm dense silicon plasmas. These first-principles calculations revealed a very interesting phenomenon of redshift-to-blueshift in K-L (1s→2p) and K-edge absorptions along both isotherm and isochore, which are absent in most continuum-lowering models of traditional plasma physics. This new physics phenomenon can be attributed to the underlying competition between the screening of deeply bound core electrons and the screening of outer-shell electrons caused by warm-dense-plasma conditions. We further demonstrate that the ratio of 1s→2p to the K-edge x-ray absorptions can be used to characterize warm-dense-plasma conditions. Eventually, based on our absorption calculations, we have established a first-principles opacity table (FPOT) for silicon in a wide range of material densities and temperatures.
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Affiliation(s)
- Valentin V Karasiev
- Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623 USA
| | - S X Hu
- Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623 USA
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14
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Jin R, Abdullah MM, Jurek Z, Santra R, Son SK. Transient ionization potential depression in nonthermal dense plasmas at high x-ray intensity. Phys Rev E 2021; 103:023203. [PMID: 33735970 DOI: 10.1103/physreve.103.023203] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 01/22/2021] [Indexed: 11/07/2022]
Abstract
The advent of x-ray free-electron lasers (XFELs), which provide intense ultrashort x-ray pulses, has brought a new way of creating and analyzing hot and warm dense plasmas in the laboratory. Because of the ultrashort pulse duration, the XFEL-produced plasma will be out of equilibrium at the beginning, and even the electronic subsystem may not reach thermal equilibrium while interacting with a femtosecond timescale pulse. In the dense plasma, the ionization potential depression (IPD) induced by the plasma environment plays a crucial role for understanding and modeling microscopic dynamical processes. However, all theoretical approaches for IPD have been based on local thermal equilibrium (LTE), and it has been controversial to use LTE IPD models for the nonthermal situation. In this work, we propose a non-LTE (NLTE) approach to calculate the IPD effect by combining a quantum-mechanical electronic-structure calculation and a classical molecular dynamics simulation. This hybrid approach enables us to investigate the time evolution of ionization potentials and IPDs during and after the interaction with XFEL pulses, without the limitation of the LTE assumption. In our NLTE approach, the transient IPD values are presented as distributions evolving with time, which cannot be captured by conventional LTE-based models. The time-integrated ionization potential values are in good agreement with benchmark experimental data on solid-density aluminum plasma and other theoretical predictions based on LTE. The present work is promising to provide critical insights into nonequilibrium dynamics of dense plasma formation and thermalization induced by XFEL pulses.
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Affiliation(s)
- Rui Jin
- Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.,Department of Physics and Astronomy, Shanghai Jiao Tong University, 200240 Shanghai, China
| | | | - Zoltan Jurek
- Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.,The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Robin Santra
- Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.,The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany.,Department of Physics, Universität Hamburg, Jungiusstrasse 9, 20355 Hamburg, Germany
| | - Sang-Kil Son
- Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.,The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
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15
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Ruby JJ, Rygg JR, Chin DA, Gaffney JA, Adrian PJ, Forrest CJ, Glebov VY, Kabadi NV, Nilson PM, Ping Y, Stoeckl C, Collins GW. Energy Flow in Thin Shell Implosions and Explosions. PHYSICAL REVIEW LETTERS 2020; 125:215001. [PMID: 33274978 DOI: 10.1103/physrevlett.125.215001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 10/30/2020] [Indexed: 06/12/2023]
Abstract
Energy flow and balance in convergent systems beyond petapascal energy densities controls the fate of late-stage stars and the potential for controlling thermonuclear inertial fusion ignition. Time-resolved x-ray self-emission imaging combined with a Bayesian inference analysis is used to describe the energy flow and the potential information stored in the rebounding spherical shock at 0.22 PPa (2.2 Gbar or billions of atmospheres pressure). This analysis, together with a simple mechanical model, describes the trajectory of the shell and the time history of the pressure at the fuel-shell interface, ablation pressure, and energy partitioning including kinetic energy of the shell and internal energy of the fuel. The techniques used here provide a fully self-consistent uncertainty analysis of integrated implosion data, a thermodynamic-path independent measurement of pressure in the petapascal range, and can be used to deduce the energy flow in a wide variety of implosion systems to petapascal energy densities.
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Affiliation(s)
- J J Ruby
- Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, USA
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14627, USA
| | - J R Rygg
- Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, USA
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14627, USA
- Department of Mechanical Engineering, University of Rochester, Rochester, New York 14627, USA
| | - D A Chin
- Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, USA
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14627, USA
| | - J A Gaffney
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - P J Adrian
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - C J Forrest
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14627, USA
| | - V Yu Glebov
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14627, USA
| | - N V Kabadi
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - P M Nilson
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14627, USA
| | - Y Ping
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - C Stoeckl
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14627, USA
| | - G W Collins
- Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, USA
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14627, USA
- Department of Mechanical Engineering, University of Rochester, Rochester, New York 14627, USA
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16
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Irfan M, Shah M, Mirza AM. Ion-acoustic dipolar vortex in degenerate magnetoplasma with ions/electrons thermal corrections. CHAOS (WOODBURY, N.Y.) 2020; 30:073142. [PMID: 32752638 DOI: 10.1063/5.0003706] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 07/06/2020] [Indexed: 06/11/2023]
Abstract
Nonlinear evolution and propagation characteristics of an ion-acoustic (IA) dipolar vortex are examined in a magnetoplasma that comprises partially degenerate electrons and dynamic ions. The adiabatic ions reduce the quantum magnetohydrodynamic equations to a modified momentum equation. The latter admits a new solution and leads to an evolution equation for the description of a coherent IA dipolar vortex. Numerical analysis reveals that variations in the relevant plasma parameters alter the evolution condition for a stable vortex. The electron exchange-correlation enhances excitation of the vortex as it extends the parametric regime associated with the stable vortex solution. On the contrary, the ion temperature lessens the nonlinear evolution of the vortex. Importantly, a degree of enhancement in the exchange-correlation potential leads to the wave dispersion and-in return-widens the vortex potential spatially. The novel nature of the derived results stresses upon the comprehension of the ordered structures in the compact stars, the magnetic mirrors, the ionosphere, the pinch devices, etc., where thermal corrections significantly impact the waves dynamics.
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Affiliation(s)
- M Irfan
- Department of Physics, University of Malakand, Chakdara, Dir (Lower), Khyber Pakhtun Khwa 18800, Pakistan
| | - M Shah
- Department of Physics, University of Malakand, Chakdara, Dir (Lower), Khyber Pakhtun Khwa 18800, Pakistan
| | - Arshad M Mirza
- Theoretical Plasma Physics Group, Department of Physics, Quaid-i-Azam University, Islamabad 45320, Pakistan
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17
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Interspecies radiative transition in warm and superdense plasma mixtures. Nat Commun 2020; 11:1989. [PMID: 32332785 PMCID: PMC7181684 DOI: 10.1038/s41467-020-15916-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 04/03/2020] [Indexed: 11/17/2022] Open
Abstract
Superdense plasmas widely exist in planetary interiors and astrophysical objects such as brown-dwarf cores and white dwarfs. How atoms behave under such extreme-density conditions is not yet well understood, even in single-species plasmas. Here, we apply thermal density functional theory to investigate the radiation spectra of superdense iron–zinc plasma mixtures at mass densities of ρ = 250 to 2000 g cm−3 and temperatures of kT = 50 to 100 eV, accessible by double-shell–target implosions. Our ab initio calculations reveal two extreme atomic-physics phenomena—firstly, an interspecies radiative transition; and, secondly, the breaking down of the dipole-selection rule for radiative transitions in isolated atoms. Our first-principles calculations predict that for superdense plasma mixtures, both interatomic radiative transitions and dipole-forbidden transitions can become comparable to the normal intra-atomic Kα-emission signal. These physics phenomena were not previously considered in detail for extreme high-density plasma mixtures at super-high energy densities. Matter at extremely high density and pressure behaves differently than at ambient conditions. Here the authors use first-principles calculations to show the existence of interspecies radiative and dipole-forbidden transitions in warm and superdense plasma mixture of iron and zinc.
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18
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Röpke G, Blaschke D, Döppner T, Lin C, Kraeft WD, Redmer R, Reinholz H. Ionization potential depression and Pauli blocking in degenerate plasmas at extreme densities. Phys Rev E 2019; 99:033201. [PMID: 30999524 DOI: 10.1103/physreve.99.033201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Indexed: 06/09/2023]
Abstract
New facilities explore warm dense matter (WDM) at conditions with extreme densities (exceeding ten times condensed matter densities) so that electrons are degenerate even at temperatures of 10-100 eV. Whereas in the nondegenerate region correlation effects such as Debye screening are relevant for the ionization potential depression (IPD), new effects have to be considered in degenerate plasmas. In addition to the Fock shift of the self-energies, the bound-state Pauli blocking becomes important with increasing density. Standard approaches to IPD such as Stewart-Pyatt and widely used opacity tables (e.g., OPAL) do not contain Pauli blocking effects for bound states. The consideration of degeneracy effects leads to a reduction of the ionization potential and to a higher degree of ionization. As an example, we present calculations for the ionization degree of carbon plasmas at T = 100 eV and extreme densities up to 40 g/cm^{3}, which are relevant to experiments that are currently scheduled at the National Ignition Facility.
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Affiliation(s)
- Gerd Röpke
- Institut für Physik, Universität Rostock, D-18051 Rostock, Germany
- Department of Theoretical Nuclear Physics, National Research Nuclear University (MEPhI), 115409 Moscow, Russia
| | - David Blaschke
- Department of Theoretical Nuclear Physics, National Research Nuclear University (MEPhI), 115409 Moscow, Russia
- Institute of Theoretical Physics, University of Wroclaw, 50-204 Wroclaw, Poland
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - Tilo Döppner
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - Chengliang Lin
- Institut für Physik, Universität Rostock, D-18051 Rostock, Germany
| | | | - Ronald Redmer
- Institut für Physik, Universität Rostock, D-18051 Rostock, Germany
| | - Heidi Reinholz
- Institut für Physik, Universität Rostock, D-18051 Rostock, Germany
- School of Physics, University of Western Australia, WA 6009 Crawley, Australia
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19
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Gunst J, Wu Y, Keitel CH, Pálffy A. Nuclear excitation by electron capture in optical-laser-generated plasmas. Phys Rev E 2018; 97:063205. [PMID: 30011546 DOI: 10.1103/physreve.97.063205] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Indexed: 11/06/2022]
Abstract
The process of nuclear excitation by electron capture in plasma environments generated by the interaction of ultrastrong optical lasers with solid-state samples is investigated theoretically. With the help of a plasma model, we perform a comprehensive study of the optimal parameters for the most efficient nuclear excitation and determine the corresponding laser setup requirements. We discern between the low-density plasma regime, modeled by scaling laws, and the high-density regime, for which we perform particle-in-cell calculations. As a nuclear transition case study we consider the 4.85-keV nuclear excitation starting from the long-lived ^{93m}Mo isomer. Our results show that the optimal plasma and laser parameters are sensitive to the chosen observable and that measurable rates of nuclear excitation and isomer depletion of ^{93m}Mo should be already achievable at laser facilities existing today.
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Affiliation(s)
- Jonas Gunst
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - Yuanbin Wu
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - Christoph H Keitel
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - Adriana Pálffy
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
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20
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Driver KP, Soubiran F, Militzer B. Path integral Monte Carlo simulations of warm dense aluminum. Phys Rev E 2018; 97:063207. [PMID: 30011453 DOI: 10.1103/physreve.97.063207] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Indexed: 06/08/2023]
Abstract
We perform first-principles path integral Monte Carlo (PIMC) and density functional theory molecular dynamics (DFT-MD) calculations to explore warm dense matter states of aluminum. Our equation of state (EOS) simulations cover a wide density-temperature range of 0.1-32.4gcm^{-3} and 10^{4}-10^{8} K. Since PIMC and DFT-MD accurately treat effects of the atomic shell structure, we find two compression maxima along the principal Hugoniot curve attributed to K-shell and L-shell ionization. The results provide a benchmark for widely used EOS tables, such as SESAME, QEOS, and models based on Thomas-Fermi and average-atom techniques. A subsequent multishock analysis provides a quantitative assessment for how much heating occurs relative to an isentrope in multishock experiments. Finally, we compute heat capacity, pair-correlation functions, the electronic density of states, and 〈Z〉 to reveal the evolution of the plasma structure and ionization behavior.
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Affiliation(s)
- K P Driver
- Department of Earth and Planetary Science, University of California, Berkeley, California 94720, USA
| | - F Soubiran
- Department of Earth and Planetary Science, University of California, Berkeley, California 94720, USA
| | - B Militzer
- Department of Earth and Planetary Science, University of California, Berkeley, California 94720, USA
- Department of Astronomy, University of California, Berkeley, California 94720, USA
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21
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Validating Continuum Lowering Models via Multi-Wavelength Measurements of Integrated X-ray Emission. Sci Rep 2018; 8:6276. [PMID: 29674688 PMCID: PMC5908972 DOI: 10.1038/s41598-018-24410-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 03/26/2018] [Indexed: 11/11/2022] Open
Abstract
X-ray emission spectroscopy is a well-established technique used to study continuum lowering in dense plasmas. It relies on accurate atomic physics models to robustly reproduce high-resolution emission spectra, and depends on our ability to identify spectroscopic signatures such as emission lines or ionization edges of individual charge states within the plasma. Here we describe a method that forgoes these requirements, enabling the validation of different continuum lowering models based solely on the total intensity of plasma emission in systems driven by narrow-bandwidth x-ray pulses across a range of wavelengths. The method is tested on published Al spectroscopy data and applied to the new case of solid-density partially-ionized Fe plasmas, where extracting ionization edges directly is precluded by the significant overlap of emission from a wide range of charge states.
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22
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Iglesias CA, Sterne PA. Comment on "Continuum Lowering and Fermi-Surface Rising in Strongly Coupled and Degenerate Plasmas". PHYSICAL REVIEW LETTERS 2018; 120:119501. [PMID: 29601771 DOI: 10.1103/physrevlett.120.119501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Indexed: 06/08/2023]
Affiliation(s)
- Carlos A Iglesias
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550, USA
| | - Philip A Sterne
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550, USA
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23
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Affiliation(s)
- S X Hu
- Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623, USA
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24
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Wu Y, Gunst J, Keitel CH, Pálffy A. Tailoring Laser-Generated Plasmas for Efficient Nuclear Excitation by Electron Capture. PHYSICAL REVIEW LETTERS 2018; 120:052504. [PMID: 29481161 DOI: 10.1103/physrevlett.120.052504] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 11/06/2017] [Indexed: 06/08/2023]
Abstract
The optimal parameters for nuclear excitation by electron capture in plasma environments generated by the interaction of ultrastrong optical lasers with solid matter are investigated theoretically. As a case study we consider a 4.85 keV nuclear transition starting from the long-lived ^{93m}Mo isomer that can lead to the release of the stored 2.4 MeV excitation energy. We find that due to the complex plasma dynamics, the nuclear excitation rate and the actual number of excited nuclei do not reach their maximum at the same laser parameters. The nuclear excitation achievable with a high-power optical laser is up to twelve and up to six orders of magnitude larger than the values predicted for direct resonant and secondary plasma-mediated excitation at the x-ray free electron laser, respectively. Our results show that the experimental observation of the nuclear excitation of ^{93m}Mo and the subsequent release of stored energy should be possible at laser facilities available today.
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Affiliation(s)
- Yuanbin Wu
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - Jonas Gunst
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - Christoph H Keitel
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - Adriana Pálffy
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
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