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Filkins T, Rosenberg MJ, Bahr RE, Katz J, Ivancic ST. Calibration of the sub-aperture backscatter system on OMEGA EP. Rev Sci Instrum 2023; 94:2890121. [PMID: 37166247 DOI: 10.1063/5.0101839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 02/03/2023] [Indexed: 05/12/2023]
Abstract
The sub-aperture backscatter (SABS) diagnostic on the OMEGA EP Laser System [Waxer et al., Opt. Photonics News 16, 30 (2005)] is a diagnostic that is used to measure the backscattered and sidescattered light during laser-plasma interaction experiments [W. L. Kruer, The Physics of Laser Plasma Interactions, Frontiers in Physics Vol. 73, edited by D. Pines (Addison-Wesley, Redwood City, CA, 1988) and Myatt et al., Phys. Plasmas 21, 055501 (2014)] that are relevant to high-energy-density physics and inertial confinement fusion. The diagnostic collects stimulated Brillouin scattering (SBS) UV light at around 351 nm and stimulated Raman scattering (SRS) in the visible-light regime in the 420-720-nm-wavelength range and provides spectrally and temporally resolved information. Five 1-in. light collectors, composed of a lens, ground glass diffuser, and coupling into a 300-μm fiber, are positioned behind the last steering mirror on one of the four beamlines to catch a portion of the beam cross section (∼1.5%) of the emission that is scattered into the beamline. The SRS light is collected in two light collectors, combined, and transported via graded index fibers to a streaked spectrometer. The SABS-SRS streak spectrometer has a temporal and spectral resolution of 100 ps and 1 nm, respectively. Three other light collectors collect, combine, and transport the SBS signal to a Hamamatsu high-voltage photodiode, where an oscilloscope digitizes the data, providing a time resolution of better than 1 ns. To obtain an absolute energy calibration of SRS measurements, light signals of known energy and wavelength were injected into the light collectors one at a time. The resulting counts on the streak camera charge-coupled device for SRS are then correlated with the incident fluence of scattered light at the light collector in order to allow a quantitative assessment of streak camera sensitivity to determine the energy of the scattered light during experiments. The measurements were performed in situ from the light collectors to the detectors. Additional offline measurements provided the transmission of the optics between the target chamber center and the light collectors.
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Affiliation(s)
- T Filkins
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
| | - M J Rosenberg
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
| | - R E Bahr
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
| | - J Katz
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
| | - S T Ivancic
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
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2
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Valdivia MP, Perez-Callejo G, Bouffetier V, Collins GW, Stoeckl C, Filkins T, Mileham C, Romanofsky M, Begishev IA, Theobald W, Klein SR, Schneider MK, Beg FN, Casner A, Stutman D. Current advances on Talbot-Lau x-ray imaging diagnostics for high energy density experiments (invited). Rev Sci Instrum 2022; 93:115102. [PMID: 36461483 DOI: 10.1063/5.0101865] [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: 06/03/2022] [Accepted: 09/14/2022] [Indexed: 06/17/2023]
Abstract
Talbot-Lau x-ray interferometry is a refraction-based diagnostic that can map electron density gradients through phase-contrast methods. The Talbot-Lau x-ray deflectometry (TXD) diagnostics have been deployed in several high energy density experiments. To improve diagnostic performance, a monochromatic TXD was implemented on the Multi-Tera Watt (MTW) laser using 8 keV multilayer mirrors (Δθ/θ = 4.5%-5.6%). Copper foil and wire targets were irradiated at 1014-1015 W/cm2. Laser pulse length (∼10 to 80 ps) and backlighter target configurations were explored in the context of Moiré fringe contrast and spatial resolution. Foil and wire targets delivered increased contrast <30%. The best spatial resolution (<6 μm) was measured for foils irradiated 80° from the surface. Further TXD diagnostic capability enhancement was achieved through the development of advanced data postprocessing tools. The Talbot Interferometry Analysis (TIA) code enabled x-ray refraction measurements from the MTW monochromatic TXD. Additionally, phase, attenuation, and dark-field maps of an ablating x-pinch load were retrieved through TXD. The images show a dense wire core of ∼60 μm diameter surrounded by low-density material of ∼40 μm thickness with an outer diameter ratio of ∼2.3. Attenuation at 8 keV was measured at ∼20% for the dense core and ∼10% for the low-density material. Instrumental and experimental limitations for monochromatic TXD diagnostics are presented. Enhanced postprocessing capabilities enabled by TIA are demonstrated in the context of high-intensity laser and pulsed power experimental data analysis. Significant advances in TXD diagnostic capabilities are presented. These results inform future diagnostic technique upgrades that will improve the accuracy of plasma characterization through TXD.
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Affiliation(s)
- M P Valdivia
- Center for Energy Research, University of California San Diego, La Jolla, California 92093, USA
| | - G Perez-Callejo
- Departamento de Física Teórica, Atómica y Óptica, Universidad de Valladolid, 47011 Valladolid, Spain
| | - V Bouffetier
- European XFEL GmbH, Holzkoppel 4, 22869 Schenefeld, Germany
| | - G W Collins
- General Atomics, Inertial Fusion Technology, San Diego, California 92121, USA
| | - C Stoeckl
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - T Filkins
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - C Mileham
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - M Romanofsky
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - I A Begishev
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - W Theobald
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - S R Klein
- University of Michigan, Ann Arbor, Michigan 48109, USA
| | - M K Schneider
- Johns Hopkins University, Applied Physics Laboratory, Laurel, Maryland 20723, USA
| | - F N Beg
- Center for Energy Research, University of California San Diego, La Jolla, California 92093, USA
| | - A Casner
- CEA-CESTA, 15 Avenue des Sablières, CS 60001, 33116 Le Barp CEDEX, France
| | - D Stutman
- ELI-NP, Institute for Physics and Nuclear Engineering, Bucharest-Magurele 077125, Romania
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Zhang S, Li J, Krauland CM, Beg FN, Muller S, Theobald W, Palastro J, Filkins T, Turnbull D, Haberberger D, Ren C, Betti R, Stoeckl C, Campbell EM, Trela J, Batani D, Scott RHH, Wei MS. Pump-depletion dynamics and saturation of stimulated Brillouin scattering in shock ignition relevant experiments. Phys Rev E 2021; 103:063208. [PMID: 34271736 DOI: 10.1103/physreve.103.063208] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 05/19/2021] [Indexed: 11/07/2022]
Abstract
As an alternative inertial confinement fusion scheme, shock ignition requires a strong converging shock driven by a high-intensity laser pulse to ignite a precompressed fusion capsule. Understanding nonlinear laser-plasma instabilities is crucial to assess and improve the laser-shock energy coupling. Recent experiments conducted on the OMEGA EP laser facility have demonstrated that such instabilities can ∼100% deplete the first 0.5 ns of the high-intensity laser. Analyses of the observed laser-generated blast wave suggest that this pump-depletion starts at ∼0.02 critical density and progresses to 0.1-0.2 critical density, which is also confirmed by the time-resolved stimulated Raman backscattering spectra. The pump-depletion dynamics can be explained by the breaking of ion-acoustic waves in stimulated Brillouin scattering. Such pump depletion would inhibit the collisional laser energy absorption but may benefit the generation of hot electrons with moderate temperatures for electron shock ignition [Phys. Rev. Lett. 119, 195001 (2017)PRLTAO0031-900710.1103/PhysRevLett.119.195001].
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Affiliation(s)
- S Zhang
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California 92093, USA
| | - J Li
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California 92093, USA
| | - C M Krauland
- Inertial Fusion Technology, General Atomics, San Diego, California 92121, USA
| | - F N Beg
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California 92093, USA
| | - S Muller
- Inertial Fusion Technology, General Atomics, San Diego, California 92121, USA
| | - W Theobald
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - J Palastro
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - T Filkins
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - D Turnbull
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - D Haberberger
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - C Ren
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.,Department of Mechanical Engineering, University of Rochester, Rochester, New York 14623, USA
| | - R Betti
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.,Department of Mechanical Engineering, University of Rochester, Rochester, New York 14623, USA
| | - C Stoeckl
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - E M Campbell
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - J Trela
- Centre Lasers Intenses et Applications, CELIA, Université de Bordeaux CEA-CNRS, 33405 Talence, France
| | - D Batani
- Centre Lasers Intenses et Applications, CELIA, Université de Bordeaux CEA-CNRS, 33405 Talence, France
| | - R H H Scott
- Central Laser Facility, STFC Rutherford Appleton Laboratory, Harwell Oxford, Didcot OX11 0QX, United Kingdom
| | - M S Wei
- Inertial Fusion Technology, General Atomics, San Diego, California 92121, USA.,Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
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Rosenberg MJ, Hernandez JE, Butler N, Filkins T, Bahr RE, Jungquist RK, Bedzyk M, Swadling G, Ross JS, Michel P, Lemos N, Eichmiller J, Sommers R, Nyholm P, Boni R, Marozas JA, Craxton RS, McKenty PW, Sharma A, Radha PB, Froula DH, Datte P, Gorman M, Moody JD, Heinmiller JM, Fornes J, Hillyard P, Regan SP. The Scattered Light Time-history Diagnostic suite at the National Ignition Facility. Rev Sci Instrum 2021; 92:033511. [PMID: 33820108 DOI: 10.1063/5.0040558] [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: 12/14/2020] [Accepted: 02/16/2021] [Indexed: 06/12/2023]
Abstract
The Scattered Light Time-history Diagnostic (SLTD) is being implemented at the National Ignition Facility (NIF) to greatly expand the angular coverage of absolute scattered-light measurements for direct- and indirect-drive inertial confinement fusion (ICF) experiments. The SLTD array will ultimately consist of 15 units mounted at a variety of polar and azimuthal angles on the NIF target chamber, complementing the existing NIF backscatter suite. Each SLTD unit collects and diffuses scattered light onto a set of three optical fibers, which transport the light to filtered photodiodes to measure scattered light in different wavelength bands: stimulated Brillouin scattering (350 nm-352 nm), stimulated Raman scattering (430 nm-760 nm), and ω/2 (695 nm-745 nm). SLTD measures scattered light with a time resolution of ∼1 ns and a signal-to-noise ratio of up to 500. Currently, six units are operational and recording data. Measurements of the angular dependence of scattered light will strongly constrain models of laser energy coupling in ICF experiments and allow for a more robust inference of the total laser energy coupled to implosions.
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Affiliation(s)
- M J Rosenberg
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - J E Hernandez
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - N Butler
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - T Filkins
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - R E Bahr
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - R K Jungquist
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - M Bedzyk
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - G Swadling
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - J S Ross
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - P Michel
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - N Lemos
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - J Eichmiller
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - R Sommers
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - P Nyholm
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - R Boni
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - J A Marozas
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - R S Craxton
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - P W McKenty
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - A Sharma
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - P B Radha
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - D H Froula
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - P Datte
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - M Gorman
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - J D Moody
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - J M Heinmiller
- Nevada National Security Site, Livermore, California 94551, USA
| | - J Fornes
- Nevada National Security Site, Livermore, California 94551, USA
| | - P Hillyard
- Nevada National Security Site, Livermore, California 94551, USA
| | - S P Regan
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
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Depierreux S, Tassin V, Antigny D, Bahr RE, Botrel N, Bourdenet R, DeDemo G, DeLaval L, Dubos O, Fariaut J, Ferri M, Filkins T, LeTacon S, Sorce C, Villette B, Vandenboomgaerde M. Experimental Evidence of Harnessed Expansion of a High-Z Plasma Using the Hollow Wall Design for Indirect Drive Inertial Confinement Fusion. Phys Rev Lett 2020; 125:255002. [PMID: 33416398 DOI: 10.1103/physrevlett.125.255002] [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: 05/13/2020] [Accepted: 11/17/2020] [Indexed: 06/12/2023]
Abstract
The effectiveness of a dome-shaped wall covered by a thin gold foil (hollow wall) [M. Vandenboomgaerde et al., Phys. Plasmas 25, 012713 (2018)PHPAEN1070-664X10.1063/1.5008669] in holding back the high-Z plasma expansion in a gas-filled hohlraum is demonstrated for the first time in experiments reproducing the irradiation conditions of indirect drive at the ignition scale. The setup exploits a 1D geometry enabling record of the complete history of the gold expansion for 8 ns by imaging its emission in multiple x-ray energy ranges featuring either the absorption zones or the thermal emission regions. The measured expansion dynamics is well reproduced by numerical simulations. This novel wall design could now be tailored for the megajoule scale to enable the propagation of the inner beams up to the equator in low gas-filled hohlraum thus allowing the fine-tuning of the irradiation symmetry on the timescale required for ignition.
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Affiliation(s)
| | - V Tassin
- CEA, DAM, DIF, F-91297 Arpajon, France
| | - D Antigny
- CEA, DAM, CESTA, F-33114 Le Barp, France
| | - R E Bahr
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
| | - N Botrel
- CEA, DAM, VALDUC, F-21120 Is sur Tille, France
| | - R Bourdenet
- CEA, DAM, VALDUC, F-21120 Is sur Tille, France
| | - G DeDemo
- CEA, DAM, VALDUC, F-21120 Is sur Tille, France
| | - L DeLaval
- CEA, DAM, CESTA, F-33114 Le Barp, France
| | - O Dubos
- CEA, DAM, DIF, F-91297 Arpajon, France
| | - J Fariaut
- CEA, DAM, DIF, F-91297 Arpajon, France
| | - M Ferri
- CEA, DAM, CESTA, F-33114 Le Barp, France
| | - T Filkins
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
| | - S LeTacon
- CEA, DAM, VALDUC, F-21120 Is sur Tille, France
| | - C Sorce
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
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Stoeckl C, Filkins T, Jungquist R, Mileham C, Pereira NR, Regan SP, Shoup MJ, Theobald W. Characterization of shaped Bragg crystal assemblies for narrowband x-ray imaging. Rev Sci Instrum 2018; 89:10G124. [PMID: 30399777 DOI: 10.1063/1.5036525] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 07/26/2018] [Indexed: 06/08/2023]
Abstract
X-ray imaging using shaped crystals in Bragg reflection is a powerful technique used in high-energy-density physics experiments. The characterization of these crystal assemblies with conventional x-ray sources is very difficult because of the required angular resolution of the order of ∼10 μrad and the narrow bandwidth of the crystal. The 10-J, 1-ps Multi-Terawatt (MTW) laser at the Laboratory for Laser Energetics was used to characterize a set of Bragg crystal assemblies. The small spot size (of the order of 5 μm) and the high power (>1018 W/cm2) of this laser make it possible to measure the spatial resolution at the intended photon energy. A set of six crystals from two different vendors was checked on MTW, showing an unexpectedly large variation in spatial resolution of up to a factor of 4.
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Affiliation(s)
- C Stoeckl
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
| | - T Filkins
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
| | - R Jungquist
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
| | - C Mileham
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
| | - N R Pereira
- Ecopulse, Inc., 7844 Vervain Ct., Springfield, Virginia 22152, USA
| | - S P Regan
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
| | - M J Shoup
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
| | - W Theobald
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA
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Rinderknecht HG, Rojas-Herrera J, Zylstra AB, Frenje JA, Gatu Johnson M, Sio H, Sinenian N, Rosenberg MJ, Li CK, Séguin FH, Petrasso RD, Filkins T, Steidle JA, Steidle JA, Traynor N, Freeman C. Impact of x-ray dose on track formation and data analysis for CR-39-based proton diagnostics. Rev Sci Instrum 2015; 86:123511. [PMID: 26724031 DOI: 10.1063/1.4938161] [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: 06/05/2023]
Abstract
The nuclear track detector CR-39 is used extensively for charged particle diagnosis, in particular proton spectroscopy, at inertial confinement fusion facilities. These detectors can absorb x-ray doses from the experiments in the order of 1-100 Gy, the effects of which are not accounted for in the previous detector calibrations. X-ray dose absorbed in the CR-39 has previously been shown to affect the track size of alpha particles in the detector, primarily due to a measured reduction in the material bulk etch rate [Rojas-Herrera et al., Rev. Sci. Instrum. 86, 033501 (2015)]. Similar to the previous findings for alpha particles, protons with energies in the range 0.5-9.1 MeV are shown to produce tracks that are systematically smaller as a function of the absorbed x-ray dose in the CR-39. The reduction of track size due to x-ray dose is found to diminish with time between exposure and etching if the CR-39 is stored at ambient temperature, and complete recovery is observed after two weeks. The impact of this effect on the analysis of data from existing CR-39-based proton diagnostics on OMEGA and the National Ignition Facility is evaluated and best practices are proposed for cases in which the effect of x rays is significant.
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Affiliation(s)
- H G Rinderknecht
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - J Rojas-Herrera
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - A B Zylstra
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - J A Frenje
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - M Gatu Johnson
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - H Sio
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - N Sinenian
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - M J Rosenberg
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - C K Li
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - F H Séguin
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - R D Petrasso
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - T Filkins
- State University of New York at Geneseo, Geneseo, New York 14454, USA
| | | | - Jessica A Steidle
- State University of New York at Geneseo, Geneseo, New York 14454, USA
| | - N Traynor
- State University of New York at Geneseo, Geneseo, New York 14454, USA
| | - C Freeman
- State University of New York at Geneseo, Geneseo, New York 14454, USA
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