Michael J. Rosenberg

Structure of Self-Generated Magnetic Fields in Laser-Solid Interaction from Proton Tomography

Jesse Griff-McMahon, C. Roca, V. Valenzuela-Villaseca, S. Malko et autres

Self-generated magnetic fields in laser-solid interactions are experimentally characterized to reveal the 3D location and local field strength, rather than path-integrated quantities, using multiview proton radiography and tomographic inversion. We infer magnetic fields that extend several millimeters off the target into the …

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Assessment of state of the art cross-beam energy transfer modeling for ignition-scale inertial fusion experiments

D. Viala, Arnaud Colaïtis, Duncan S. Barlow, L. Ceurvorst et autres

We present the first experimental validation at ignition scale of a linear kinetic ion-acoustic wave model for cross-beam energy transfer (CBET), using data from recent polar direct-drive experiments at the National Ignition Facility. In this configuration, CBET plays a critical role in …

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Structure of self-generated magnetic fields in laser-solid interaction from proton tomography

Jesse Griff-McMahon, Christopher A. Walsh, V. Valenzuela-Villaseca, S. Malko et autres

Strong magnetic fields are naturally self-generated in high-power, laser-solid interactions through the Biermann-battery mechanism. This work experimentally characterizes the 3D location and strength of these fields, rather than path-integrated quantities, through multi-view proton radiography and tomographic inversion on the OMEGA laser. We …

Correlating hot-electron preheat from the two-plasmon decay instability to ρR degradation for direct-drive implosions on OMEGA

Duc Luong Cao, W. Theobald, Michael J. Rosenberg, L. Ceurvorst et autres

Focused experiments were performed with the goal of isolating the impact of hot-electron preheat on compression in deuterium–tritium (DT) layered, direct-drive implosions on OMEGA. Preheat from the hot-electrons generated by two-plasmon–decay (TPD) activity was varied through the incident laser intensity, with the …

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A new neutron time-of-flight detector for yield and ion-temperature measurements in DT implosions on OMEGA

Arnold Schwemmlein, C. J. Forrest, James P. Knauer, Hannah McClow et autres

A new neutron time-of-flight (nTOF) detector for yield and ion-temperature measurements in deuterium-tritium (DT) implosions was designed, installed, and calibrated on the OMEGA Laser System. This detector was installed at θ = 46.8° from the vertical and φ = 84.9°, previously a …

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Approaching hydro-equivalent ignition in laser direct-drive via target design optimization using novel statistical modeling

A. Lees, R. Betti, V. Gopalaswamy, J. P. Knauer et autres

Laser direct-drive offers significant advantages in terms of target simplicity, improved energy coupling, and large fuel masses over indirect drive. However, performance degradations from hydrodynamic and laser-plasma instabilities seeded and driven by the direct illumination pose limitations on the parameter space available …

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Three-dimensional reconstruction of inertial confinement fusion hot-spot plasma from x-ray and nuclear diagnostics on OMEGA

Kristen Churnetski, K. M. Woo, W. Theobald, R. Betti et autres

Multidimensional effects degrade the neutron yield and the compressed areal density of laser-direct-drive inertial confinement fusion implosions of layered deuterium–tritium cryogenic targets on the OMEGA Laser System with respect to 1D radiation-hydrodynamic simulation predictions. A comprehensive physics-informed 3D reconstruction effort is under …

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An experimentally informed design process for future inertial confinement fusion facilities

R. K. Follett, Arnaud Colaïtis, Igor V. Igumenshchev, Duc Luong Cao et autres

The achievement of ignition in the laboratory has renewed interest in defining the requirements for a future high-gain inertial confinement fusion (ICF) facility. Our best chance of predicting future ICF performance is with 3-D radiation hydrodynamic simulations that have been benchmarked against …

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Erratum: Ion kinetic dynamics in strongly-shocked plasmas relevant to ICF (2017 Nucl. Fusion 57 066014)

Hans G. Rinderknecht, P. A. Amendt, Michael J. Rosenberg, C.K. Li et autres

Progress toward hydro-equivalent ignition in OMEGA direct-drive DT-layered implosions

L. Ceurvorst, R. Betti, V. Gopalaswamy, A. Lees et autres

Considerable progress has been made in deuterium-tritium-layered implosion experiments on the OMEGA Laser System, bringing the prospects for thermonuclear ignition in direct-drive configurations with megajoule-class lasers closer to reality. Doing so has required navigating the balance between improved 1D performance and multidimensional …

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Exploration of polar direct drive wetted foam concepts for neutron sources on the National Ignition Facility laser

Gregory E. Kemp, C. B. Yeamans, M. Hohenberger, Suhas D. Bhandarkar et autres

A multi-laboratory collaborative effort is currently exploring the feasibility of laser direct drive liquid deuterium–tritium (DT) wetted foam inertial confinement fusion concepts being considered for novel neutron sources on the National Ignition Facility (NIF) laser. In contrast to the laser indirect drive …

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Proton radiography inversions with source extraction and comparison to mesh methods

Jesse Griff-McMahon, V. Valenzuela-Villaseca, S. Malko, G. Fiksel et autres

Proton radiography is a central diagnostic technique for measuring electromagnetic (EM) fields in high-energy-density, laser-produced plasmas. In this technique, protons traverse the plasma where they accumulate small EM deflections which lead to variations in the proton fluence pattern on a detector. Path-integrated …

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