1
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Dorst RS, Constantin CG, Schaeffer DB, Pilgram JJ, Niemann C. Planar laser induced fluorescence mapping of a carbon laser produced plasma. Rev Sci Instrum 2022; 93:103518. [PMID: 36319323 DOI: 10.1063/5.0099171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 08/23/2022] [Indexed: 06/16/2023]
Abstract
We present measurements of ion velocity distribution profiles obtained by laser induced fluorescence (LIF) on an explosive laser produced plasma. The spatiotemporal evolution of the resulting carbon ion velocity distribution was mapped by scanning through the Doppler-shifted absorption wavelengths using a tunable, diode-pumped laser. The acquisition of these data was facilitated by the high repetition rate capability of the ablation laser (1 Hz), which allowed for the accumulation of thousands of laser shots in short experimental times. By varying the intensity of the LIF beam, we were able to explore the effects of fluorescence power against the laser irradiance in the context of evaluating the saturation vs the non-saturation regime. The small size of the LIF beam led to high spatial resolution of the measurement compared to other ion velocity distribution measurement techniques, while the fast-gate operation mode of the camera detector enabled the measurement of the relevant electron transitions.
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Affiliation(s)
- R S Dorst
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C G Constantin
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA
| | - D B Schaeffer
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
| | - J J Pilgram
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C Niemann
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA
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2
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Johnson CL, Malko S, Fox W, Schaeffer DB, Fiksel G, Adrian PJ, Sutcliffe GD, Birkel A. Proton deflectometry with in situ x-ray reference for absolute measurement of electromagnetic fields in high-energy-density plasmas. Rev Sci Instrum 2022; 93:023502. [PMID: 35232152 DOI: 10.1063/5.0064263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 01/03/2022] [Indexed: 06/14/2023]
Abstract
We report a technique of proton deflectometry that uses a grid and an in situ reference x-ray grid image for precise measurements of magnetic fields in high-energy-density plasmas. A D3He fusion implosion provides a bright point source of both protons and x-rays, which is split into beamlets by a grid. The protons undergo deflections as they propagate through the plasma region of interest, whereas the x-rays travel along straight lines. The x-ray image, therefore, provides a zero-deflection reference image. The line-integrated magnetic fields are inferred from the shifts of beamlets between the deflected (proton) and reference (x-ray) images. We developed a system for analysis of these data, including automatic algorithms to find beamlet locations and to calculate their deflections from the reference image. The technique is verified in an experiment performed at OMEGA to measure a nonuniform magnetic field in vacuum and then applied to observe the interaction of an expanding plasma plume with the magnetic field.
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Affiliation(s)
- C L Johnson
- Rowan University, Glassboro, New Jersey 08028, USA
| | - S Malko
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - W Fox
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - D B Schaeffer
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08544, USA
| | - G Fiksel
- Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - P J Adrian
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - G D Sutcliffe
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - A Birkel
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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3
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Kaloyan M, Ghazaryan S, Constantin CG, Dorst RS, Heuer PV, Pilgram JJ, Schaeffer DB, Niemann C. Raster Thomson scattering in large-scale laser plasmas produced at high repetition rate. Rev Sci Instrum 2021; 92:093102. [PMID: 34598480 DOI: 10.1063/5.0059244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 08/17/2021] [Indexed: 06/13/2023]
Abstract
We present optical Thomson scattering measurements of electron density and temperature in a large-scale (∼2 cm) exploding laser plasma produced by irradiating a solid target with a high-energy (5-10 J) laser pulse at a high repetition rate (1 Hz). The Thomson scattering diagnostic matches this high repetition rate. Unlike previous work performed in single shots at much higher energies, the instrument allows for point measurements anywhere inside the plasma by automatically translating the scattering volume using motorized stages as the experiment is repeated at 1 Hz. Measured densities around 4 × 1016 cm-3 and temperatures around 7 eV result in a scattering parameter near unity, depending on the distance from the target. The measured spectra show the transition from collective scattering close to the target to non-collective scattering at larger distances. Densities obtained by fitting the weakly collective spectra agree to within 10% with an irradiance calibration performed via Raman scattering in nitrogen.
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Affiliation(s)
- M Kaloyan
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095, USA
| | - S Ghazaryan
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095, USA
| | - C G Constantin
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095, USA
| | - R S Dorst
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095, USA
| | - P V Heuer
- Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623, USA
| | - J J Pilgram
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095, USA
| | - D B Schaeffer
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
| | - C Niemann
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095, USA
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4
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Schaeffer DB, Fox W, Rosenberg MJ, Park HS, Fiksel G, Kalantar D. Measurements of electron temperature in high-energy-density plasmas using gated x-ray pinhole imaging. Rev Sci Instrum 2021; 92:043524. [PMID: 34243484 DOI: 10.1063/5.0043833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 03/22/2021] [Indexed: 06/13/2023]
Abstract
We present measurements of spatially and temporally resolved electron temperature in high-energy-density plasmas using gated x-ray pinhole imagers. A 2D image of bremsstrahlung x-ray self-emission from laser-driven plasma plumes is detected at the same time through two pinholes covered with different filter materials. By comparing the attenuated signal through each filter, a spatially resolved electron temperature as low as 0.1 keV can be estimated. Measurements of the plasma plume taken from different directions indicate that imaging through extended plasmas has a negligible effect on the temperature estimates. Methods for estimating the expected signal, selecting filters, and incorporating the response of the detector are discussed.
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Affiliation(s)
- D B Schaeffer
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
| | - W Fox
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
| | - M J Rosenberg
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - H-S Park
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - G Fiksel
- Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - D Kalantar
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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5
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Dorst RS, Heuer PV, Schaeffer DB, Constantin CG, Niemann C. Measurements of ion velocity distributions in a large scale laser-produced plasma. Rev Sci Instrum 2020; 91:103103. [PMID: 33138584 DOI: 10.1063/5.0013447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 09/11/2020] [Indexed: 06/11/2023]
Abstract
Laser-produced plasma velocity distributions are an important, but difficult quantity to measure. We present a non-invasive technique for measuring individual charge state velocity distributions of laser-produced plasmas using a high temporal and spectral resolution monochromator. The novel application of this technique is its ability to detect particles up to 7 m from their inception (significantly larger than most laboratory plasma astrophysics experiments, which take place at or below the millimeter scale). The design and assembly of this diagnostic is discussed in terms of maximizing the signal to noise ratio, maximizing the spatial and temporal resolution, and other potential use cases. The analysis and results of this diagnostic are demonstrated by directly measuring the time-of-flight velocity of all ion charge states in a laser produced carbon plasma.
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Affiliation(s)
- R S Dorst
- Department of Physics and Astronomy, University of California - Los Angeles, Los Angeles, California 90095, USA
| | - P V Heuer
- Department of Physics and Astronomy, University of California - Los Angeles, Los Angeles, California 90095, USA
| | - D B Schaeffer
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
| | - C G Constantin
- Department of Physics and Astronomy, University of California - Los Angeles, Los Angeles, California 90095, USA
| | - C Niemann
- Department of Physics and Astronomy, University of California - Los Angeles, Los Angeles, California 90095, USA
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6
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Schaeffer DB, Fox W, Follett RK, Fiksel G, Li CK, Matteucci J, Bhattacharjee A, Germaschewski K. Direct Observations of Particle Dynamics in Magnetized Collisionless Shock Precursors in Laser-Produced Plasmas. Phys Rev Lett 2019; 122:245001. [PMID: 31322368 DOI: 10.1103/physrevlett.122.245001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 05/22/2019] [Indexed: 06/10/2023]
Abstract
We present the first laboratory observations of time-resolved electron and ion velocity distributions in magnetized collisionless shock precursors. Thomson scattering of a probe laser beam was used to observe the interaction of a laser-driven, supersonic piston plasma expanding through an ambient plasma in an external magnetic field. From the Thomson-scattered spectra we measure time-resolved profiles of electron density, temperature, and ion flow speed, as well as spatially resolved magnetic fields from proton radiography. We observe direct evidence of the coupling between piston and ambient plasmas, including the acceleration of ambient ions driven by magnetic and pressure gradient electric fields, and deformation of the piston ion flow, key steps in the formation of magnetized collisionless shocks. Even before a shock has fully formed, we observe strong density compressions and electron heating associated with the pileup of piston ions. The results demonstrate that laboratory experiments can probe particle velocity distributions relevant to collisionless shocks, and can complement, and in some cases overcome, the limitations of similar measurements undertaken by spacecraft missions.
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Affiliation(s)
- D B Schaeffer
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
| | - W Fox
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - R K Follett
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - G Fiksel
- Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - C K Li
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - J Matteucci
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
| | - A Bhattacharjee
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - K Germaschewski
- Space Science Center, University of New Hampshire, Durham, New Hampshire 03824, USA
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7
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Matteucci J, Fox W, Bhattacharjee A, Schaeffer DB, Moissard C, Germaschewski K, Fiksel G, Hu SX. Biermann-Battery-Mediated Magnetic Reconnection in 3D Colliding Plasmas. Phys Rev Lett 2018; 121:095001. [PMID: 30230875 DOI: 10.1103/physrevlett.121.095001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 06/29/2018] [Indexed: 06/08/2023]
Abstract
Recent experiments have demonstrated magnetic reconnection between colliding plasma plumes, where the reconnecting magnetic fields were self-generated in the plasma by the Biermann-battery effect. Using fully kinetic 3D simulations, we show the full evolution of the magnetic fields and plasma in these experiments, including self-consistent magnetic field generation about the expanding plume. The collision of the two plasmas drives the formation of a current sheet, where reconnection occurs in a strongly time- and space-dependent manner, demonstrating a new 3D reconnection mechanism. Specifically, we observe a fast, vertically localized Biermann-mediated reconnection, an inherently 3D process where the temperature profile in the current sheet coupled with the out-of-plane ablation density profile conspires to break inflowing field lines, reconnecting the field downstream. Fast reconnection is sustained by both the Biermann effect and the traceless electron pressure tensor, where the development of plasmoids appears to modulate the contribution of the latter. We present a simple and general formulation to consider the relevance of Biermann-mediated reconnection in general astrophysical scenarios.
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Affiliation(s)
- J Matteucci
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
| | - W Fox
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - A Bhattacharjee
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - D B Schaeffer
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
| | - C Moissard
- Laboratoire de Physique des Plasmas, École Polytechnique, Paris 75252, France
| | - K Germaschewski
- Space Science Center, University of New Hampshire, Durham, New Hampshire 03824, USA
| | - G Fiksel
- Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - S X Hu
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
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8
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Schaeffer DB, Fox W, Haberberger D, Fiksel G, Bhattacharjee A, Barnak DH, Hu SX, Germaschewski K. Generation and Evolution of High-Mach-Number Laser-Driven Magnetized Collisionless Shocks in the Laboratory. Phys Rev Lett 2017; 119:025001. [PMID: 28753335 DOI: 10.1103/physrevlett.119.025001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Indexed: 06/07/2023]
Abstract
We present the first laboratory generation of high-Mach-number magnetized collisionless shocks created through the interaction of an expanding laser-driven plasma with a magnetized ambient plasma. Time-resolved, two-dimensional imaging of plasma density and magnetic fields shows the formation and evolution of a supercritical shock propagating at magnetosonic Mach number M_{ms}≈12. Particle-in-cell simulations constrained by experimental data further detail the shock formation and separate dynamics of the multi-ion-species ambient plasma. The results show that the shocks form on time scales as fast as one gyroperiod, aided by the efficient coupling of energy, and the generation of a magnetic barrier between the piston and ambient ions. The development of this experimental platform complements present remote sensing and spacecraft observations, and opens the way for controlled laboratory investigations of high-Mach number collisionless shocks, including the mechanisms and efficiency of particle acceleration.
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Affiliation(s)
- D B Schaeffer
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
| | - W Fox
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - D Haberberger
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - G Fiksel
- Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - A Bhattacharjee
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540, USA
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - D H Barnak
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
- Fusion Science Center for Extreme States of Matter, University of Rochester, Rochester, New York 14623, USA
| | - S X Hu
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - K Germaschewski
- Space Science Center, University of New Hampshire, Durham, New Hampshire 03824, USA
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9
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Schaeffer DB, Constantin CG, Bondarenko AS, Everson ET, Niemann C. Spatially resolved Thomson scattering measurements of the transition from the collective to the non-collective regime in a laser-produced plasma. Rev Sci Instrum 2016; 87:11E701. [PMID: 27910524 DOI: 10.1063/1.4955304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We present optical Thomson scattering results that image for the first time in a single measurement the spatial transition from collective to non-collective scattering. Data were taken in the Phoenix laser laboratory at the University of California, Los Angeles. The Raptor laser was used to ablate a carbon plasma, which was diagnosed with the frequency-doubled Phoenix laser serving as a Thomson scattering probe. Scattered light was collected from the laser plasma up to 10 cm from the target surface and up to 10 us after ablation, and imaged with high spatial and spectral resolutions. The results show a strong Thomson collective feature close to the target surface that smoothly transitions to a non-collective feature over several mm.
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Affiliation(s)
- D B Schaeffer
- Department of Physics and Astronomy, University of California- Los Angeles, Los Angeles, California 90095, USA
| | - C G Constantin
- Department of Physics and Astronomy, University of California- Los Angeles, Los Angeles, California 90095, USA
| | - A S Bondarenko
- Department of Physics and Astronomy, University of California- Los Angeles, Los Angeles, California 90095, USA
| | - E T Everson
- Department of Physics and Astronomy, University of California- Los Angeles, Los Angeles, California 90095, USA
| | - C Niemann
- Department of Physics and Astronomy, University of California- Los Angeles, Los Angeles, California 90095, USA
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10
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Clark SE, Everson ET, Schaeffer DB, Bondarenko AS, Constantin CG, Niemann C, Winske D. Enhanced collisionless shock formation in a magnetized plasma containing a density gradient. Phys Rev E Stat Nonlin Soft Matter Phys 2014; 90:041101. [PMID: 25375430 DOI: 10.1103/physreve.90.041101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Indexed: 06/04/2023]
Abstract
Two-dimensional hybrid simulations of super-Alfvénic expanding debris plasma interacting with an inhomogeneous ambient plasma are presented. The simulations demonstrate improved collisionless coupling of energy to the ambient ions when encountering a density gradient. Simulations of an expanding cylinder running into a step function gradient are performed and compared to a simple analytical theory. Magnetic flux probe data from a laboratory shock experiment are compared to a simulation with a more realistic debris expansion and ambient ion density. The simulation confirms that a shock is formed and propagates within the high density region of ambient plasma.
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Affiliation(s)
- S E Clark
- Department of Physics and Astronomy, University of California-Los Angeles, Los Angeles, California 90095, USA
| | - E T Everson
- Department of Physics and Astronomy, University of California-Los Angeles, Los Angeles, California 90095, USA
| | - D B Schaeffer
- Department of Physics and Astronomy, University of California-Los Angeles, Los Angeles, California 90095, USA
| | - A S Bondarenko
- Department of Physics and Astronomy, University of California-Los Angeles, Los Angeles, California 90095, USA
| | - C G Constantin
- Department of Physics and Astronomy, University of California-Los Angeles, Los Angeles, California 90095, USA
| | - C Niemann
- Department of Physics and Astronomy, University of California-Los Angeles, Los Angeles, California 90095, USA
| | - D Winske
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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Bondarenko AS, Schaeffer DB, Everson ET, Constantin CG, Clark SE, Niemann C. Feasibility of characterizing laser-ablated carbon plasmas via planar laser induced fluorescence. Rev Sci Instrum 2012; 83:10E515. [PMID: 23127022 DOI: 10.1063/1.4733562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Planar laser induced fluorescence (PLIF) imaging can potentially assess ion distributions and coupling in the context of super-Alfvénic ablation plasma expansions into magnetized background plasmas. In this feasibility study, we consider the application of PLIF to rapidly expanding carbon plasmas generated via energetic laser ablation of graphite. By utilizing hydrodynamic and collisional-radiative simulations, we identify schemes accessible to commercially available tunable lasers for the C I atom, the C II ion, and the C V ion. We then estimate the signal-to-noise ratios yielded by the schemes under reasonable experimental configurations.
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Affiliation(s)
- A S Bondarenko
- Department of Physics and Astronomy, University of California-Los Angeles, Los Angeles, California 90095, USA.
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12
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Clark SE, Schaeffer DB, Bondarenko AS, Everson ET, Constantin CG, Niemann C. Magnetic field measurements in low density plasmas using paramagnetic Faraday rotator glass. Rev Sci Instrum 2012; 83:10D503. [PMID: 23126847 DOI: 10.1063/1.4728214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Paramagnetic Faraday rotator glass (rare-earth doped borosilicate) with a high Verdet constant will be used to measure the magnetic field inside of low density Helium plasmas (T(e) ~ 5 eV, T(i) ~ 1 eV) with a density of n ~ 10(12) cm(-3). Linearly polarized light is sent through the glass such that the plane of polarization is rotated by an angle that depends on the strength of the magnetic field in the direction of propagation and the length of the crystal (6 mm). The light is then passed into an analyzer and photo-detector setup to determine the change in polarization angle. This setup can detect magnetic fields up to 5 kG with a resolution of <5 G and a temporal resolution on the order of a nanosecond. The diagnostic will be used to characterize the structure and evolution of laser-driven collisionless shocks in large magnetized plasmas.
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Affiliation(s)
- S E Clark
- Department of Physics and Astronomy, University of California - Los Angeles, Los Angeles, California 90095, USA
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13
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Schaeffer DB, Kugland NL, Constantin CG, Everson ET, Van Compernolle B, Ebbers CA, Glenzer SH, Niemann C. A scalable multipass laser cavity based on injection by frequency conversion for noncollective Thomson scattering. Rev Sci Instrum 2010; 81:10D518. [PMID: 21033873 DOI: 10.1063/1.3460626] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A scalable setup using injection by frequency conversion to establish a multipassing cavity for noncollective Thomson scattering on low density plasmas is presented. The cavity is shown to support >10 passes through the target volume with a 400% increase in energy on target versus a single-pass setup. Rayleigh scattering experiments were performed and demonstrate the viability of the cell to study low density plasmas of the order of 10(12)-10(13) cm(-3). A high-repetition, low-energy, single-pass Thomson scattering setup was also performed on the University of California, Los Angeles Large Plasma Device and shows that the multipass cavity could have a significant advantage over the high-repetition approach due to the cavity setup's inherently higher signal per shot.
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Affiliation(s)
- D B Schaeffer
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA.
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