A. J. Mackinnon
A5040969819- Laser-Plasma Interactions and Diagnostics
- Laser-induced spectroscopy and plasma
- High-pressure geophysics and materials
- Laser-Matter Interactions and Applications
- Nuclear Physics and Applications
- Atomic and Molecular Physics
- Laser Design and Applications
- Ion-surface interactions and analysis
- Magnetic confinement fusion research
- Advanced X-ray Imaging Techniques
- Combustion and Detonation Processes
- Cold Fusion and Nuclear Reactions
- Diamond and Carbon-based Materials Research
- Energetic Materials and Combustion
- Astro and Planetary Science
- Laser Material Processing Techniques
- Atomic and Subatomic Physics Research
- Electron and X-Ray Spectroscopy Techniques
- Advanced Optical Sensing Technologies
- Planetary Science and Exploration
- Radiation Detection and Scintillator Technologies
- Fusion materials and technologies
- Advanced X-ray and CT Imaging
- Particle accelerators and beam dynamics
- Nuclear reactor physics and engineering
Lawrence Livermore National Laboratory
2015-2024
Lawrence Livermore National Security
2005-2024
Massachusetts Institute of Technology
2009-2023
SLAC National Accelerator Laboratory
2016-2023
General Atomics (United States)
2007-2023
Rutherford Appleton Laboratory
2001-2023
The University of Texas at Austin
2023
University of California, Los Angeles
2023
Florida Agricultural and Mechanical University
2023
University of Rochester
2011-2022
An explanation for the energetic ions observed in PetaWatt experiments is presented. In solid target with focused intensities exceeding 1020 W/cm2, high-energy electron generation, hard bremsstrahlung, and protons have been on backside of target. this report, an attempt made to explain physical process present that will presence these protons, as well number, energy, angular spread experiment. particular, we hypothesize hot electrons produced front are sent through back off target, where...
An intense collimated beam of high-energy protons is emitted normal to the rear surface thin solid targets irradiated at 1 PW power and peak intensity 3x10(20) W cm(-2). Up 48 J ( 12%) laser energy transferred 2x10(13) >10 MeV. The spectrum exhibits a sharp cutoff as high 58 MeV on axis which decreases in with increasing off angle. Proton induced nuclear processes have been observed used characterize beam.
In recent Petawatt laser experiments at Lawrence Livermore National Laboratory, several hundred joules of 1 μm light in 0.5–5.0-ps pulses with intensities up to 3×1020 W cm−2 were incident on solid targets and produced a strongly relativistic interaction. The energy content, spectra, angular patterns the photon, electron, ion radiations have all been diagnosed number ways, including novel (to physics) nuclear activation techniques. About 40%–50% is converted broadly beamed hot electrons....
A new technique is described for the isochoric heating (i.e., at constant volume) of matter to high energy-density plasma states (>10(5) J/g) on a picosecond time scale (10(-12)sec). An intense, collimated, ultrashort-pulse beam protons--generated by high-intensity laser pulse--is used isochorically heat solid density material temperature several eV. The duration shorter than significant hydrodynamic expansion occur; hence heated warm dense state. Using spherically shaped targets, focused...
MeV-proton production from solid targets irradiated by 100-fs laser pulses at intensities above 1x10(20) W cm(-2) has been studied as a function of initial target thickness. For foils 100 microm thick the proton beam was characterized an energy spectrum temperature 1.4 MeV with cutoff 6.5 MeV. When thickness reduced to 3 3.2+/-0.3 24 These observations are consistent modeling showing enhanced density electrons rear surface for thinnest targets, which predicts increased acceleration and...
The acceleration of high-energy ion beams (up to several tens mega-electron-volts per nucleon) following the interaction short (t < 1 ps) and intense (I λ 2 > 1018 W˙cm-2˙μm-2) laser pulses with solid targets has been one most active areas research in last few years. exceptional properties these (high brightness high spectral cutoff, directionality laminarity, burst duration) distinguish them from lower-energy ions accelerated earlier experiments at moderate intensities. In view properties,...
Due to their particular properties, the beams of multi-MeV protons generated during interaction ultraintense (I&gt;1019 W/cm2) short pulses with thin solid targets are most suited for use as a particle probe in laser-plasma experiments. The recently developed proton imaging technique employs point-projection scheme diagnostic tool detection electric fields In recent investigations carried out at Rutherford Appleton Laboratory (RAL, UK), wide range conditions relevance inertial...
Abstract Obtaining a burning plasma is critical step towards self-sustaining fusion energy 1 . A one in which the reactions themselves are primary source of heating plasma, necessary to sustain and propagate burn, enabling high gain. After decades research, here we achieve burning-plasma state laboratory. These experiments were conducted at US National Ignition Facility, laser facility delivering up 1.9 megajoules pulses with peak powers 500 terawatts. We use lasers generate X-rays radiation...
The National Ignition Facility (NIF) at Lawrence Livermore Laboratory includes a precision laser system now capable of delivering 1.8 MJ 500 TW 0.35-μm light to target. NIF has been operational since March 2009. A variety experiments have completed in support NIF's mission areas: national security, fundamental science, and inertial fusion energy. capabilities infrastructure are place its missions with nearly 60 X-ray, optical, nuclear diagnostic systems. primary goal the Campaign (NIC) on...
A series of cryogenic, layered deuterium-tritium (DT) implosions have produced, for the first time, fusion energy output twice peak kinetic imploding shell. These experiments at National Ignition Facility utilized high density carbon ablators with a three-shock laser pulse (1.5 MJ in 7.5 ns) to irradiate low gas-filled ($0.3\text{ }\text{ }\mathrm{mg}/\mathrm{cc}$ helium) bare depleted uranium hohlraums, resulting hohlraum radiative temperature $\ensuremath{\sim}290\text{ }\mathrm{eV}$. The...
Deuterium-tritium inertial confinement fusion implosion experiments on the National Ignition Facility have demonstrated yields ranging from 0.8 to 7×10(14), and record fuel areal densities of 0.7 1.3 g/cm2. These implosions use hohlraums irradiated with shaped laser pulses 1.5-1.9 MJ energy. The peak power duration at were varied, as capsule ablator dopant concentrations shell thicknesses. We quantify level hydrodynamic instability mix into hot spot measured elevated absolute x-ray emission...
Abstract In a burning plasma state 1–7 , alpha particles from deuterium–tritium fusion reactions redeposit their energy and are the dominant source of heating. This has recently been achieved at US National Ignition Facility 8 using indirect-drive inertial-confinement fusion. Our experiments use laser-generated radiation-filled cavity (a hohlraum) to spherically implode capsules containing deuterium tritium fuel in central hot spot where occur. We have developed more efficient hohlraums...
An inertial fusion implosion on the National Ignition Facility, conducted August 8, 2021 (N210808), recently produced more than a megajoule of yield and passed Lawson's criterion for ignition [Phys. Rev. Lett. 129, 075001 (2022)]. We describe experimental improvements that enabled N210808 present first measurements from an igniting plasma in laboratory. metrics like product hot-spot energy pressure squared, absence self-heating, increased by ∼35%, leading to record values enhancement...
We present the design of first igniting fusion plasma in laboratory by Lawson's criterion that produced 1.37 MJ energy, Hybrid-E experiment N210808 (August 8, 2021) [Phys. Rev. Lett. 129, 075001 (2022)10.1103/PhysRevLett.129.075001]. This uses indirect drive inertial confinement approach to heat and compress a central "hot spot" deuterium-tritium (DT) fuel using surrounding dense DT piston. Ignition occurs when heating from absorption α particles created process overcomes loss mechanisms...
An indirect-drive inertial fusion experiment on the National Ignition Facility was driven using 2.05 MJ of laser light at a wavelength 351 nm and produced 3.1±0.16 total yield, producing target gain G=1.5±0.1 exceeding unity for first time in laboratory [Phys. Rev. E 109, 025204 (2024)10.1103/PhysRevE.109.025204]. Herein we describe experimental evidence increased drive capsule additional energy control over known degradation mechanisms, which are critical to achieving high performance....
In an experimental study of the physics fast ignition, characteristics hot electron source at laser intensities up to 1020 W cm−2 have been measured and a diagnosis heating depth by electrons has initiated. Generation with more than 30% efficiency observed. Preliminary data suggest temperatures kT in range 300–800 eV.
A study of the properties multi-MeV proton emission from thin foils following ultraintense laser irradiation has been carried out. It shown that protons are emitted, in a quasilaminar fashion, region transverse size order 100-200 microm. The imaging source equivalent to those much smaller located several hundred microm front foil. This finding obtained by analyzing radiographs periodically structured test objects, and is corroborated observations laser-heated thick targets.
The influence of the plasma density scale length on production MeV protons from thin foil targets irradiated at $I{\ensuremath{\lambda}}^{2}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}5\ifmmode\times\else\texttimes\fi{}{10}^{19}\phantom{\rule{0ex}{0ex}}\mathrm{W}\mathrm{cm}{}^{\ensuremath{-}2}$ has been studied. With an unperturbed foil, with energy $>20\phantom{\rule{0ex}{0ex}}\mathrm{MeV}$ were formed in exponential spectrum a temperature...
Electron transport within solid targets, irradiated by a high-intensity short-pulse laser, has been measured imaging K(alpha) radiation from high- Z layers (Cu, Ti) buried in low- (CH, Al) foils. Although the laser spot is approximately 10 microm [full width at half maximum (FWHM)], electron beam spreads to > or =70 FWHM <20 of penetration into an Al target then, depths >100 microm, diverges with 40 degree spreading angle. Monte Carlo and analytic models are compared our data. We find that...
A novel physical phenomenon has been observed following the interaction of an intense (10(19) W/cm(2)) laser pulse with underdense plasma. Long-lived, macroscopic bubblelike structures have detected through deflection that associated electric charge separation causes in a proton probe beam. These are interpreted as remnants cloud relativistic solitons generated plasma by ultraintense pulse. This interpretation is supported analytical study soliton evolution, particle-in-cell simulations, and...
Electromagnetic (E/B) fields generated by the interaction with plasmas of long-pulse, low-intensity laser beams relevant to inertial confinement fusion have been measured for first time using novel monoenergetic proton radiography methods. High-resolution, time-gated images a plastic foil driven 10(14) W/cm(2) implied B approximately 0.5 MG and E 1.5 x 10(8) V/m. Simulations these experiments LASNEX+LSP performed are in overall (though not exact) agreement data both field strengths spatial...
Metal foil targets were irradiated with 1 mum wavelength (lambda) laser pulses of 5 ps duration and focused intensities (I) up to 4x10;{19} W cm;{-2}, giving values both Ilambda;{2} pulse comparable those required for fast ignition inertial fusion. The divergence the electrons accelerated into target was determined from spatially resolved measurements x-ray K_{alpha} emission transverse probing plasma formed on back foils. Comparison other published data shows that it increases is...
Relativistic self-channeling of a picosecond laser pulse in preformed plasma near critical density has been observed both experimentally and 3D particle-in-cell simulations. Optical probing measurements indicate the formation single pulsating propagation channel, typically about 5 \ensuremath{\mu}m diameter. The computational results reveal importance channel relativistic electrons traveling with light corresponding self-generated magnetic field.