A5054581481- Nuclear Physics and Applications
- Laser-Plasma Interactions and Diagnostics
- High-pressure geophysics and materials
- Atomic and Subatomic Physics Research
- Cold Fusion and Nuclear Reactions
- Nuclear physics research studies
- Laser-induced spectroscopy and plasma
- Neutrino Physics Research
- Quantum, superfluid, helium dynamics
- Advanced NMR Techniques and Applications
- Particle physics theoretical and experimental studies
- Radiation Detection and Scintillator Technologies
- Magnetic confinement fusion research
- Medical Imaging Techniques and Applications
- Astronomical and nuclear sciences
- Quantum Chromodynamics and Particle Interactions
- Dark Matter and Cosmic Phenomena
- Advanced MRI Techniques and Applications
- Particle Detector Development and Performance
- Fusion materials and technologies
- Advanced Radiotherapy Techniques
- Radioactive Decay and Measurement Techniques
- Advanced optical system design
- Nuclear reactor physics and engineering
- Non-Invasive Vital Sign Monitoring
Siemens (United States)
2024
Los Alamos National Laboratory
2020-2024
University of Tennessee at Knoxville
2013-2024
Lawrence Livermore National Laboratory
2023-2024
Los Alamos National Security (United States)
2024
Oak Ridge National Laboratory
2013
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...
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....
Abstract Indirect Drive Inertial Confinement Fusion Experiments on the National Ignition Facility (NIF) have achieved a burning plasma state with neutron yields exceeding 170 kJ, roughly 3 times prior record and necessary stage for igniting plasmas. The results are despite multiple sources of degradations that lead to high variability in performance. Results shown here, first time, include an empirical correction factor mode-2 asymmetry regime addition previously determined corrections...
Ground-state two-proton (2p) radioactivity is a decay mode found in isotopes of elements with even atomic numbers located beyond the drip line. So far, this exotic process has been experimentally observed few light and medium-mass nuclides Z less than or equal to 30. In study, using state-of-the-art nuclear density functional theory, we globally analyze 2p for first time identify candidates heavier strontium. We predict cases where competition between emission alpha may be observed. nuclei...
Background: Neutron-skin thickness is an excellent indicator of isovector properties atomic nuclei. As such, it correlates strongly with observables in finite nuclei that depend on neutron-to-proton imbalance and the nuclear symmetry energy characterizes equation state neutron-rich matter. A rich worldwide experimental program involving studies rare isotopes, parity-violating electron scattering, astronomical observations devoted to pinning down sector models.Purpose: We assess theoretical...
We review experimental neutron imaging of inertial confinement fusion sources, including the systems that have been used in our measurements at National Ignition Facility. These allow with 10 µm resolution for deuterium-deuterium and deuterium-tritium sources mean radius up to 400 µm, neutrons scattered lower energy remaining cold fuel. are critical understanding burn volume three-dimensional effects can reduce yields.
We report the first observation of parity-violating 2.2 MeV gamma-ray asymmetry $A^{np}_\gamma$ in neutron-proton capture using polarized cold neutrons incident on a liquid parahydrogen target at Spallation Neutron Source Oak Ridge National Laboratory. isolates $\Delta I=1$, \mbox{$^{3}S_{1}\rightarrow {^{3}P_{1}}$} component weak nucleon-nucleon interaction, which is dominated by pion exchange and can be directly related to single coupling constant either DDH meson model or pionless EFT....
This manuscript examines the correlations between hot-spot velocity (an observable signature of residual kinetic energy), low-mode implosion asymmetries, and burn amplification in inertial confinement fusion implosions on National Ignition Facility (NIF). Using a combination two-dimensional axis-symmetric three-dimensional radiation-hydrodynamic simulations coupled to neutronics, we find that for typical NIF implosions, stagnation asymmetry multiplies observed anywhere from 80% 120%, while...
The change in the power balance, temporal dynamics, emission weighted size, temperature, mass, and areal density of inertially confined fusion plasmas have been quantified for experiments that reach target gains up to 0.72. It is observed as gain rises, increased rates self-heating initially overcome expansion losses. This leads reacting peak production at later times with mass lower densities. Analytic models are consistent observations inferences how these quantities evolve rate...
While nuclear fusion ignition has been achieved at the National Ignition Facility in inertial confinement (ICF) experiments, obtaining higher gain and more efficient burn is still desired. In that regard, increasing compression of fuel an important factor. recent indirect-drive capsule implosions, SQ-n campaign testing hypothesis reducing hydrodynamic growth perturbations key to achieving high-density carbon based-ablators for ICF. uses a design lower adiabat with ramped foot laser pulse...
The joint LANL/LLNL nuclear imaging team has acquired the first gamma-ray images of inertial confinement fusion implosions at National Ignition Facility. image provides crucial information to help characterize inertially confined fuel and ablator assembly stagnation, that would be difficult acquire from neutron or x-ray observations. Gamma visualizes both gamma radiation emitted directly in deuterium–tritium (DT) reactions as well rays produced when DT neutrons scatter inelastically on...
Neutron beta decay is one of the most fundamental processes in nuclear physics and provides sensitive means to uncover details weak interaction. can evaluate ratio axial-vector vector coupling constants standard model, λ = g A / V , through multiple correlations. The Nab experiment will carry out measurements electron-neutrino correlation parameter a with precision δ 10 −3 Fierz interference term b 3 × unpolarized free neutron decay. These results, along more precise measurement lifetime,...
We report the first precision measurement of parity-violating asymmetry in direction proton momentum with respect to neutron spin, reaction ^{3}He(n,p)^{3}H, using capture polarized cold neutrons an unpolarized active ^{3}He target. The is a result weak interaction between nucleons, which remains one least well-understood aspects electroweak theory. provides important benchmark for modern effective field theory and potential model calculations. Measurements like this are necessary determine...
Delta-Rice is an HDF5 (The HDF Group et al., 2020) filter plugin that was developed to compress digitized detector signals recorded by the Nab experiment (Fry 2019), a fundamental neutron physics experiment.This two-step process where incoming data passed through pre-processing and then compressed with Rice coding.A routine for determining optimal dataset provided along example GPU deployment.When applied collected acquisition system, this method produced output files 29% their initial size,...
Abstract Background Linear attenuation coefficients (LACs) in positron emission tomography combined with computed (PET/CT) are derived from CT scans that utilize energy‐integrating detectors (EID‐CT). These LACs inaccurate when iodine contrast has been injected. Photon counting detector (PCD‐CT) may be able to improve the accuracy. Purpose To investigate whether PCD‐CT can PET/CT quantitative Methods Two experiments were performed: one only and PET CT. The first experiment used an electron...
Background: The outstanding capabilities of modern Positron Emission Tomography (PET) to highlight small tumor lesions and provide pathological function assessment are at peril from image quality degradation caused by respiratory cardiac motion. However, the advent long axial field-of-view (LAFOV) scanners with increased sensitivity, alongside precise time-of-flight (TOF) PET systems, enables acquisition ultrafast time resolution images, which can be used for estimating correcting cyclic...
We describe our current understanding of the variability and degradation mechanisms observed through a series five indirectly driven inertial fusion implosions fielded at National Ignition Facility in fall 2021, four which attempted to reproduce first experiment achieve Lawson's criterion for ignition with thermonuclear yield 1.35 MJ on August 8, 2021. A large number absolutely calibrated (imaging, time-resolved, spectrally resolved) x-ray neutron diagnostics are NIF along multiple lines...
We report the first measurement of 10B(α,n)13N reaction in a polar-direct-drive exploding pusher (PDXP) at National Ignition Facility (NIF). This work is motivated by need to develop alternative mix diagnostics, radiochemistry being focus here. The target composed 65/35 at. % deuterium–tritium (DT) fill surrounded roughly 30 μm thick beryllium ablator. inner portion ablator doped with 10 10B. Radiation-hydrodynamics calculations were performed 1D optimize both remaining boron rho-R and DT...