A5010676793- Laser-Plasma Interactions and Diagnostics
- Laser-induced spectroscopy and plasma
- Laser-Matter Interactions and Applications
- Magnetic confinement fusion research
- High-pressure geophysics and materials
- Nuclear Physics and Applications
- Atomic and Molecular Physics
- Laser Design and Applications
- Cold Fusion and Nuclear Reactions
- Advanced X-ray Imaging Techniques
- Particle accelerators and beam dynamics
- Solar and Space Plasma Dynamics
- Laser Material Processing Techniques
- Atomic and Subatomic Physics Research
- Plasma Diagnostics and Applications
- Radiation Detection and Scintillator Technologies
- High-Velocity Impact and Material Behavior
- Astro and Planetary Science
- Planetary Science and Exploration
- Ionosphere and magnetosphere dynamics
- Solid State Laser Technologies
- Dust and Plasma Wave Phenomena
- Diamond and Carbon-based Materials Research
- Advanced Surface Polishing Techniques
- Ion-surface interactions and analysis
The University of Texas at Austin
2015-2024
Lawrence Livermore National Laboratory
2007-2024
Sandia National Laboratories
2009-2021
University of California, San Diego
2021
Ludwig-Maximilians-Universität München
2016
Peking University
2016
National Technical Information Service
2011
Office of Scientific and Technical Information
2011
Fusion Academy
2009
Fusion (United States)
2006-2009
Laser-plasma accelerators of only a centimetre's length have produced nearly monoenergetic electron bunches with energy as high 1 GeV. Scaling these compact to multi-gigaelectronvolt would open the prospect building X-ray free-electron lasers and linear colliders hundreds times smaller than conventional facilities, but GeV barrier has so far proven insurmountable. Here, by applying new petawatt laser technology, we produce spectrum prominently peaked at 2 few per cent spread unprecedented...
An intense laser pulse focused onto a plasma can excite nonlinear waves. Under appropriate conditions, electrons from the background are trapped in wave and accelerated to ultra-relativistic velocities. This scheme is called wakefield accelerator. In this work, we present results acceleration experiment using petawatt-class wakefields as well nanoparticles assist injection of into accelerating phase wakefields. We find that 10-cm-long, nanoparticle-assisted accelerator generate 340 pC, 10 ±...
The plasma astrophysical $S$ factor for the $^{3}\mathrm{He}(d,p)^{4}\mathrm{He}$ fusion reaction was measured first time at temperatures of few keV, using interaction intense ultrafast laser pulses with molecular deuterium clusters mixed $^{3}\mathrm{He}$ atoms. Different proportions ${\mathrm{D}}_{2}$ and or ${\mathrm{CD}}_{4}$ were in gas target order to allow measurement cross section reaction. yield 14.7 MeV protons from extract low energies. Our result is agreement other...
Two different methods have been employed to determine the plasma temperature in a laser-cluster fusion experiment on Texas Petawatt laser. In first, was derived from time-of-flight data of deuterium ions ejected exploding D(2) or CD(4) clusters. second, measured ratio rates two nuclear reactions occurring at same time: D(d,(3)He)n and (3)He(d,p)(4)He. The temperatures determined by these agree well, which indicates that (i) ion energy distribution is not significantly distorted when travel...
The kinetic energy of hot (multi-keV) ions from the laser-driven Coulomb explosion deuterium clusters and resulting fusion yield in plasmas formed these exploding has been investigated under a variety conditions using Texas Petawatt laser. An optimum laser intensity was found for producing neutrons cluster with corresponding average ion energies 14 keV. substantial volume (1-10 mm(3)) laser-cluster interaction produced by petawatt peak power pulse led to 1.6×10(7) single shot 120 J, 170 fs...
Relativistic transparency enables volumetric laser interaction with overdense plasmas and direct acceleration of electrons to relativistic velocities. The dense electron current generates a magnetic filament field strength the order amplitude ($>$10$^5$ T). traps radially, enabling efficient conversion energy into MeV photons by oscillations in filament. use microstructured targets stabilizes hosing instabilities associated relativistically transparent interactions, resulting robust...
In this work, we present a new and general method for measuring the astrophysical S-factor of nuclear reactions in laser-induced plasmas apply it to d(d,n)$^{3}$He. The experiment was performed with Texas Petawatt laser, which delivered 150-270 fs pulses energy ranging from 90 180 J D$_{2}$ or CD$_{4}$ molecular clusters. After removing background noise, used measured time-of-flight data energetic deuterium ions obtain their distribution. We derive using distribution ions, volume fusion...
We present experimental observation of above-threshold ionization (ATI) electrons produced by the neon K shell in a laser field where intensity exceeds ${10}^{20}\phantom{\rule{0.16em}{0ex}}\mathrm{W}/{\mathrm{cm}}^{2}$. An array plastic scintillating calorimeter detectors was used to measure high-energy at four angles forward direction. Coarse energy resolution obtained using aluminum filters several thicknesses block lower-energy electrons. A threshold around...
We report on the increase in accelerated electron number and energy using compound parabolic concentrator (CPC) targets from a short-pulse ($\ensuremath{\sim}150$ fs), high-intensity ($>{10}^{18}$ W/${\mathrm{cm}}^{2}$), high-contrast ($\ensuremath{\sim}{10}^{8}$) laser-solid interaction. experimental measurements CPC where hot-electron temperature is enhanced up to $\ensuremath{\sim}9$ times when compared planar targets. The measured target...
We report on experiments in which the Texas Petawatt laser irradiated a mixture of deuterium or deuterated methane clusters and helium-3 gas, generating three types nuclear fusion reactions: D($d$,${}^{3}$He)$n$, D($d$,$t$)$p$, ${}^{3}$He($d$,$p$)${}^{4}$He. measured yields neutrons protons from these reactions found them to agree with based simple cylindrical plasma model using known cross sections parameters. Within our measurement errors, products were isotropically distributed. Plasma...
Experiments investigating fracture and resistance to plastic deformation at fast strain rates (>106 s−1) were performed via laser ablation on thin sheets of aluminum alloys. Single crystal high purity (Al-HP) a single 1100 series alloy (AA1100) prepared investigate the role impurity particles. Specimens +3 wt. % Mg (Al+3Mg) three different grain sizes also studied determine effect size. In present experiments, exhibited highest spall strength over Al+3Mg. Fracture characterization...
The irradiation of few nm thick targets by a finite-contrast high-intensity short-pulse laser results in strong pre-expansion these at the arrival time main pulse. decompress to near and lower than critical densities plasmas extending over micrometers, i.e. multiple wavelengths. interaction pulse with such highly localized but inhomogeneous target leads generation short channel further self-focusing beam. Experiments GHOST system UT Austin using measured non-Maxwellian, peaked electron...
High-flux, high-repetition-rate neutron sources are of interest in studying neutron-induced damage processes materials relevant to fusion, ultimately guiding designs for future fusion reactors. Existing and upcoming petawatt laser systems show great potential fulfill this need. Here, we present a platform producing laser-driven beams based on cryogenic liquid jet target an adaptable stacked lithium beryllium converter. Selected ion diagnostics enable monitoring the key parameters both beams....
A new type of compact high-resolution high-sensitivity gamma-ray spectrometer for short-pulse intense gamma-rays (250 keV to 50 MeV) has been developed by combining the principles scintillators and attenuation spectrometers. The first prototype this scintillator (SAS) was tested successfully in Trident laser experiments at LANL. Later versions have used extensively Texas Petawatt Austin, TX, more recently OMEGA-EP LLE, Rochester, NY. SAS is particularly useful high-repetition-rate...
Three types of neutron detectors (plastic scintillation detectors, indium activation and CR-39 track detectors) were calibrated for the measurement 2.45 MeV DD fusion yields from deuterium cluster experiment on Texas Petawatt Laser. A Cf-252 source neutrons generated laser-cluster interaction used as sources. The such that they can detect up to 10(8) per shot in current mode under high electromagnetic pulse environments. Indium successfully measured low 10(4) 10(11) neutrons. use a allowed...
An experimental and simulation study of warm dense carbon foams at ambient density (ne ∼ 1021 cm−3) is presented. This isochorically heated motivated by their potential application in carbon-atmosphere white-dwarf envelopes, where there are modeling uncertainties due to the equation state. The on an approximately picosecond time scale with a laser-accelerated proton beam. cooling expansion can be modeled appropriately initialized radiation-hydrodynamics codes; xRAGE code used this work....
Abstract The interaction of an intense laser with a solid foil target can drive $$\sim$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>∼</mml:mo> </mml:math> TV/m electric fields, accelerating ions to MeV energies. In this study, we experimentally observe that structured targets dramatically enhance proton acceleration in the normal sheath regime. At Texas Petawatt Laser facility, compared from $$1\, {\upmu }\hbox {m}$$ <mml:mrow> <mml:mn>1</mml:mn> <mml:mspace/>...
Abstract We report production of a self-injected, collimated (8 mrad divergence), 600 pC bunch electrons with energies up to 350 MeV from petawatt laser-driven plasma accelerator in electron density n e = 10 17 cm −3 , an order magnitude lower than previous self-injected laser-plasma accelerators. The energy the focused drive laser pulse (150 J, 150 fs) was distributed over several hot spots. Simulations show that these spots remained independent 5 interaction length, and produced weakly...
The Texas Petawatt Laser is operational with experimental campaigns executed in both F/40 and F3 target chambers. Recent improvements have resulted intensities of >2×1021 W/cm2 on target. Experimental highlights include, accelerated electron energies >2 GeV, DD fusion ion temperatures >25 keV isochorically heated solids to 10-50 eV.
We measured the average deuterium cluster size within a mixture of clusters and helium gas by detecting Rayleigh scattering signals. The from was comparable to that pure when total backing pressure temperature were same as those gas. According these measurements, depends on not partial in mixture. To characterize source further, Faraday cup used measure kinetic energy ions resulting Coulomb explosion upon irradiation an intense ultrashort pulse. indeed acquired similar amount target,...
Electron self-injection into a laser-plasma accelerator (LPA) driven by the Texas Petawatt (TPW) laser is reported at plasma densities 1.7 - 6.2 × 1017 cm−3. Energy and charge of electron beam, ranging from 0.5 GeV to 2 tens hundreds pC, respectively, depended strongly on beam quality density. Angular divergence was consistently around mrad (FWHM), while shot-to-shot pointing fluctuations were limited ±1.4 rms. Betatron x-rays with keV photon energy are also clearly observed.
We experimentally and numerically investigated the cascade random-quasi-phase-matched harmonic generation in polycrystalline zinc selenide with tightly focused mid-infrared nanosecond laser pulses. observed a sharp transition between two distinct intensity scaling regimes as function of pump energy from sub IN to super IN, where I is N order. To gain an understanding observations this complex nonlinear process, we carried out simulations coupled three-wave mixing equations random grain sizes...