A5048961017- Nuclear Physics and Applications
- Radiation Detection and Scintillator Technologies
- Superconducting and THz Device Technology
- Physics of Superconductivity and Magnetism
- Laser-Plasma Interactions and Diagnostics
- Atomic and Subatomic Physics Research
- X-ray Spectroscopy and Fluorescence Analysis
- High-pressure geophysics and materials
- Nuclear reactor physics and engineering
- Particle Detector Development and Performance
- Advanced Semiconductor Detectors and Materials
- Medical Imaging Techniques and Applications
- Ion-surface interactions and analysis
- Advanced X-ray and CT Imaging
- Particle Accelerators and Free-Electron Lasers
- Magnetic properties of thin films
- Nuclear physics research studies
- Cold Fusion and Nuclear Reactions
- Electron and X-Ray Spectroscopy Techniques
- Magnetic confinement fusion research
- Advanced X-ray Imaging Techniques
- Advanced Chemical Physics Studies
- Astro and Planetary Science
- Calibration and Measurement Techniques
- Gyrotron and Vacuum Electronics Research
Lawrence Livermore National Laboratory
2014-2025
Los Alamos National Laboratory
2011-2014
Rutherford Appleton Laboratory
2014
Sandia National Laboratories
2014
Massachusetts Institute of Technology
2014
Fusion Academy
2014
Fusion (United States)
2014
General Atomics (United States)
2014
CEA DAM Île-de-France
2014
National Security Technologies (United States)
2011
A neutron imaging diagnostic has recently been commissioned at the National Ignition Facility (NIF). This new system is an important tool for inertial fusion studies NIF measuring size and shape of burning DT plasma during ignition stage Inertial Confinement Fusion (ICF) implosions. The technique utilizes a pinhole aperture, placed between source detector. detection measures two dimensional distribution neutrons passing through pinhole. designed to collect images times. long flight path this...
Neutron yields are measured at the National Ignition Facility (NIF) by an extensive suite of neutron activation diagnostics. Neutrons interact with materials whose reaction cross sections threshold just below fusion production energy, providing accurate measure primary unscattered neutrons without contribution from lower-energy scattered neutrons. Indium samples mounted on diagnostic instrument manipulators in NIF target chamber, 25–50 cm source, to 2.45 MeV deuterium-deuterium through...
Transparent ceramics combine the scintillation performance of single crystals with ruggedness and processability glass. We have developed a versatile, scaleable fabrication method, wherein nanoparticle feedstock is consolidated at temperatures well below melting to form inch-scale phase-pure transparent optical scatter α <0.1 cm<sup>-1</sup>. fabricated Cerium-doped Gadolinium Garnets light yields ~50,000 Ph/MeV energy resolution <5% 662 keV. also methods sheets high-Z ceramic...
First results from the analysis of neutron image data collected on implosions cryogenically layered deuterium-tritium capsules during 2011-2012 National Ignition Campaign are reported. The span a variety experimental designs aimed at increasing stagnation pressure central hotspot and areal density surrounding fuel assembly. Images neutrons produced by deuterium–tritium fusion reactions in presented, as well images that scatter dense compared with 1D 2D model predictions, consistency checked...
The National Ignition Facility has been used to compress deuterium-tritium an average areal density of ~1.0±0.1 g cm(-2), which is 67% the ignition requirement. These conditions were obtained using 192 laser beams with total energy 1-1.6 MJ and peak power up 420 TW create a hohlraum drive shaped profile, peaking at soft x-ray radiation temperature 275-300 eV. This pulse delivered series shocks that compressed capsule containing cryogenic radius 25-35 μm. Neutron images implosion estimate...
Transparent polycrystalline ceramic scintillators based on the garnet structure and incorporating gadolinium for high stopping power are being developed use in gamma spectrometers. Optimization of energy resolution spectroscopy involves refining material composition light yield, developing ceramics fabrication methodology homogeneity, as well selecting size geometry scintillator to match photodetector characteristics readout electronics. We have demonstrated 4% at 662 keV 0.05 cm <formula...
We are working to perfect the growth of divalent Eu-doped strontium iodide single crystals and optimize design SrI<sub>2</sub>(Eu)-based gamma ray spectrometers. SrI<sub>2</sub>(Eu) offers a light yield in excess 100,000 photons/MeV proportionality surpassing that Ce-doped lanthanum bromide. Thermal x-ray diffraction analyses SrI<sub>2</sub> EuI<sub>2</sub> indicate an excellent match melting crystallographic parameters, very modest thermal expansion anisotropy. have demonstrated energy...
Dense plasma focii (DPFs) are appealing as energy efficient sources of short pulses ions, neutrons, and x rays. The output these is expected to scale with input current (I4), but has been shown drop at the MA level [S. K. H. Auluck, “On failure neutron yield scaling in dense focus,” Phys. Plasmas 30, 080701 (2023)]. New results on MegaJOuLe Neutron Imaging Radiography DPF showed production agreement beyond previously observed drop. This work provides insight into pinch formation a reports...
Recently discovered scintillators for gamma ray spectroscopy - single-crystal SrI<sub>2</sub>(Eu), GYGAG(Ce) transparent ceramic and Bismuth-loaded plastics offer resolution fabrication advantages compared to commercial scintillators, such as NaI(Tl) standard PVT plastic. Energy at 662 keV of 2.7% is obtained with while 4.5% GYGAG(Ce). A new scintillator radiographic imaging systems, GLO(Eu), offers high light yield 70,000 Photons/MeV, stopping, low radiation damage. Implementation Gd-based...
We have built a high-resolution high-efficiency superconducting soft x-ray spectrometer for synchrotron-based fluorescence-detected absorption spectroscopy. The sensor is 3×3 array of 200×200 μm2 Nb–Al–Al2O3–Al–Nb tunnel junctions with an energy resolution around 15 eV below 1 keV and total count rate capability ≈100 000 counts/s. This cooled to ≈0.1 K by two-stage adiabatic demagnetization refrigerator while held at the end 40-cm-long cold finger that can be inserted into UHV sample chamber...
Transparent ceramics offer an alternative to single crystals for scintillator applications such as gamma ray spectroscopy and radiography. We have developed a versatile, scaleable fabrication method, using Flame Spray Pyrolysis (FSP) produce feedstock which is readily converted into phase-pure transparent ceramics. measure integral light yields in excess of 80,000 Ph/MeV with Cerium-doped Garnets, excellent optical quality. Avalanche photodiode readout Garnets provides resolution near 6%....
A dense plasma focus (DPF) is a relatively compact coaxial gun, which completes its discharge as Z-pinch. These devices are designed to operate at variety of scales produce short (<100 ns) pulses ions, X-rays, and/or neutrons. LLNL recently constructed and brought into operation new device, the MegaJOuLe Neutron Imaging Radiography (MJOLNIR) DPF, for radiography high-yield operations. This device has been commissioned achieved neutron yields up 3.8E11 neutrons/pulse 2.5-MA peak current while...
Normal conductor-insulator-superconductor (NIS) junctions promise to be interesting for x-ray and phonon sensing applications, in particular due the expected self-cooling of N electrode by tunneling current. Such cooling would enable operation active element sensor below cryostat temperature at a correspondingly higher sensitivity. It also allow use NIS as microcoolers. At present, this has not been realized large area (suitable number detector applications). In article, we discuss detailed...
Development of the Europium-doped Strontium Iodide scintillator, SrI <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (Eu), involves advances in crystal growth, optics and readout methodology for prototype detectors. We have demonstrated energy resolution 3% at 662 keV a 26 cm <sup xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> (Eu) crystal, which is equivalent to performance obtained with Cerium-doped Lanthanum Bromide size. Compared...
There is an ever increasing demand for gamma-ray detectors which can achieve good energy resolution, high detection efficiency, and room-temperature operation. We are working to address each of these requirements through the development large volume SrI <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (Eu) scintillator detectors. In this work, we have evaluated a variety crystals with volumes >;10 cm <sup...
We are developing cryogenic high-resolution X-ray, Gamma-ray and neutron spectrometers based on superconducting Mo/Cu transition edge sensors. Here we discuss the sensor design for different applications, present photolithographic fabrication techniques, outline future detector development to increase spectrometer sensitivity.
We are developing new scintillator materials that offer potential for high resolution gamma ray spectroscopy at low cost. Single crystal SrI <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (Eu) offers ~3% 662 keV, in sizes of ~1 <sup xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> . have developed ceramics processing technology allowing us to achieve cubic inch scale transparent ceramic scintillators offering performance superior...
Superconducting tunnel junction (STJ) X-ray spectrometers have been developed for synchrotron-based high-resolution soft spectroscopy. We are quantifying the improvements in sensitivity and signal-to-noise ratio that STJ can offer analysis of dilute specimens over conventional semiconductor grating spectrometers. present analytical equations to quantify terms spectrometer resolution, detection efficiency count rate capabilities as a function line separation spectral background. discuss...