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Swanson KJ, Jaar GS, Mayes DC, Mancini RC, Ivanov VV, Astanovitskiy AL, Dmitriev O, Klemmer AW, De La Cruz C, Dolan D, Porwitzky A, Loisel GP, Bailey JE. Development and integration of photonic Doppler velocimetry as a diagnostic for radiation driven experiments on the Z-machine. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2022; 93:043502. [PMID: 35489931 DOI: 10.1063/5.0084638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 03/09/2022] [Indexed: 06/14/2023]
Abstract
Plasma density measurements are key to a wide variety of high-energy-density (HED) and laboratory astrophysics experiments. We present a creative application of photonic Doppler velocimetry (PDV) from which time- and spatially resolved electron density measurements can be made. PDV has been implemented for the first time in close proximity, ∼6 cm, to the high-intensity radiation flux produced by a z-pinch dynamic hohlraum on the Z-machine. Multiple PDV probes were incorporated into the photoionized gas cell platform. Two probes, spaced 4 mm apart, were used to assess plasma density and uniformity in the central region of the gas cell during the formation of the plasma. Electron density time histories with subnanosecond resolution were extracted from PDV measurements taken from the gas cells fielded with neon at 15 Torr. As well, a null shot with no gas fill in the cell was fielded. A major achievement was the low noise high-quality measurements made in the harsh environment produced by the mega-joules of x-ray energy emitted at the collapse of the z-pinch implosion. To evaluate time dependent radiation induced effects in the fiber optic system, two PDV noise probes were included on either side of the gas cell. The success of this alternative use of PDV demonstrates that it is a reliable, precise, and affordable new electron density diagnostic for radiation driven experiments and more generally HED experiments.
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Affiliation(s)
- K J Swanson
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - G S Jaar
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - D C Mayes
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - R C Mancini
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - V V Ivanov
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - A L Astanovitskiy
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - O Dmitriev
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - A W Klemmer
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - C De La Cruz
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - D Dolan
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - A Porwitzky
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G P Loisel
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J E Bailey
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
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Mayes DC, Mancini RC, Lockard TE, Hall IM, Bailey JE, Loisel GP, Nagayama T, Rochau GA, Liedahl DA. Observation of ionization trends in a laboratory photoionized plasma experiment at Z. Phys Rev E 2021; 104:035202. [PMID: 34654098 DOI: 10.1103/physreve.104.035202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 08/09/2021] [Indexed: 11/07/2022]
Abstract
We report experimental and modeling results for the charge state distribution of laboratory photoionized neon plasmas in the first systematic study over nearly an order of magnitude range of ionization parameter ξ∝F/N_{e}. The range of ξ is achieved by flexibility in the experimental platform to adjust either the x-ray drive flux F at the sample or the electron number density N_{e} or both. Experimental measurements of photoionized plasma conditions over such a range of parameters enable a stringent test of atomic kinetics models used within codes that are applied to photoionized plasmas in the laboratory and astrophysics. From experimental transmission data, ion areal densities are extracted by spectroscopic analysis that is independent of atomic kinetics modeling. The measurements reveal the net result of the competition between photon-driven ionization and electron-driven recombination atomic processes as a function of ξ as it affects the charge state distribution. Results from radiation-hydrodynamics modeling calculations with detailed inline atomic kinetics modeling are compared with the experimental results. There is good agreement in the mean charge and overall qualitative similarities in the trends observed with ξ but significant quantitative differences in the fractional populations of individual ions.
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Affiliation(s)
- D C Mayes
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - R C Mancini
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - T E Lockard
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - I M Hall
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - J E Bailey
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G P Loisel
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - T Nagayama
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G A Rochau
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - D A Liedahl
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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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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