L. A. Bernstein
A5056920801- Nuclear Physics and Applications
- Nuclear physics research studies
- Nuclear reactor physics and engineering
- Astronomical and nuclear sciences
- Quantum Chromodynamics and Particle Interactions
- Atomic and Molecular Physics
- Laser-Plasma Interactions and Diagnostics
- Nuclear Materials and Properties
- Particle accelerators and beam dynamics
- Radiation Detection and Scintillator Technologies
- Graphite, nuclear technology, radiation studies
- Advanced Chemical Physics Studies
- X-ray Spectroscopy and Fluorescence Analysis
- Radiopharmaceutical Chemistry and Applications
- Rare-earth and actinide compounds
- Particle physics theoretical and experimental studies
- Atomic and Subatomic Physics Research
- Nuclear and radioactivity studies
- Radioactive contamination and transfer
- Radiation Therapy and Dosimetry
- Advanced NMR Techniques and Applications
- High-pressure geophysics and materials
- Superconducting Materials and Applications
- Laser-induced spectroscopy and plasma
- Medical Imaging Techniques and Applications
University of California, Berkeley
2016-2025
Lawrence Berkeley National Laboratory
2016-2025
Lawrence Livermore National Laboratory
2012-2024
Brookhaven National Laboratory
2023
Helmholtz Institute Mainz
2017
Johannes Gutenberg University Mainz
2017
University of California System
2015
Los Alamos National Laboratory
2012-2014
Sandia National Laboratories
2012-2014
General Atomics (United States)
2012-2014
For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as proof of principle various concepts. Following Lawson criterion, an ignited plasma is one where heating power high enough overcome all physical processes that cool plasma, creating positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, state can begin "burn propagation" into surrounding cold fuel, enabling possibility energy...
Psychological tests typically include a response scale whose purpose it is to organize and constrain the options available respondents facilitate scoring. One such Likert scale, which initially was introduced have specific 5-point form. In practice, scales varied considerably in nature number of options. However, relatively little consensus exists regarding several questions that emerged use Likert-type items. First, there “psychometrically optimal” options? Second, better an even or odd...
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...
On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:msub><a:mrow><a:mi>G</a:mi></a:mrow><a:mrow><a:mtext>target</a:mtext></a:mrow></a:msub></a:mrow></a:math> of 1.5. This is first laboratory demonstration exceeding “scientific breakeven” (or <c:math xmlns:c="http://www.w3.org/1998/Math/MathML"...
Ignition requires precisely controlled, high convergence implosions to assemble a dense shell of deuterium-tritium (DT) fuel with ρR&gt;∼1 g/cm2 surrounding 10 keV hot spot ρR ∼ 0.3 g/cm2. A working definition ignition has been yield ∼1 MJ. At this the α-particle energy deposited in would have ∼200 kJ, which is already ∼10 × more than kinetic typical implosion. The National Campaign includes low dudded layers study and optimize hydrodynamic assembly diagnostics rich environment. mixture...
Accurate nuclear data are essential for advances in fields related to energy, security, medicine and space exploration, with similar needs shared by multiple applications. This perspective addresses some of the latest applications suggests work ensure both near- long-term progress
Discrete $\ensuremath{\gamma}$ rays directly connecting states of a superdeformed (SD) band in ${}^{194}\mathrm{Hg}$ to the yrast have been discovered. Thus, excitation energies and spins all members lowest SD are established for first time, together with their likely parity. The decays from its ${10}^{+}$ ${12}^{+}$ states, which lie 4204.8 4407.4 keV above normal-deformed same spins.
Radiative strength functions (RSFs) in $^{93\ensuremath{-}98}\mathrm{Mo}$ have been extracted using the $(^{3}\mathrm{He},\ensuremath{\alpha}\ensuremath{\gamma})$ and $(^{3}\mathrm{He},{^{3}\mathrm{He}}^{'}\ensuremath{\gamma})$ reactions. The RSFs are U shaped as function of \ensuremath{\gamma} energy with a minimum at around ${E}_{\ensuremath{\gamma}}=3 \mathrm{MeV}$. values increase neutron number because low-energy tail giant electric dipole resonance nuclear deformation. unexpected...
The first inertial confinement fusion implosion experiments with equimolar deuterium-tritium thermonuclear fuel have been performed on the National Ignition Facility. These use 0.17 mg of potential for ignition and significant yield conditions. has fielded as a cryogenic layer inside spherical plastic capsule that is mounted in center cylindrical gold hohlraum. Heating hohlraum 192 laser beams total energy 1.6 MJ produces soft x-ray field 300 eV temperature. ablation pressure produced by...
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...
A new experimental technique is presented using proton-$\ensuremath{\gamma}\mathrm{\text{\ensuremath{-}}}\ensuremath{\gamma}$ correlations from $^{94}\mathrm{Mo}(d,p)^{95}\mathrm{Mo}$ reactions which allows for the model-independent extraction of photon strength function at various excitation energies primary $\ensuremath{\gamma}$-ray decay quasicontinuum to individual low-lying levels. Detected particle provide entrance into residual nucleus while transitions levels specify discrete states...
The $\ensuremath{\gamma}$-ray strength function in the quasicontinuum has been measured for ${}^{231--233}$Th, ${}^{232,233}$Pa, and ${}^{237--239}$U using Oslo method. All eight nuclei show a pronounced increase $\ensuremath{\gamma}$ at ${\ensuremath{\omega}}_{\mathrm{SR}}\ensuremath{\approx}2.4$ MeV, which is interpreted as low-energy $M1$ scissors resonance (SR). total found to be ${B}_{\mathrm{SR}}=9--11\phantom{\rule{0.16em}{0ex}}{\ensuremath{\mu}}_{N}^{2}$ when integrated over 1--4 MeV...
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 orbital M1-scissors resonance (SR) has been measured for the first time in quasi-continuum of actinides. Particle-gamma coincidences are recorded with deuteron and 3He induced reactions on 232Th. residual nuclei 231,232,233Th 232,233Pa show an unexpectedly strong integrated strength $B_{M1} = 11-15 \mu_{n}^{2}$ Egamma=1.0 - 3.5 MeV region. increased gamma-decay probability actinides due to SR is important cross-section calculations future fuel cycles fast nuclear reactors may also have...
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...
Particle-gamma coincidences have been measured to obtain gamma-ray spectra as a function of excitation energy for 231-233Th and 237-239U. The level densities, which were extracted using the Oslo method, show constant temperature behavior. isotopes display very similar temperatures in quasi-continuum, however, even-odd reveal entropy increase Delta S compared their even-even neighbors. excess depends on available orbitals last unpaired valence neutron heated nuclear system. Also, experimental...
A well-established knowledge of nuclear phenomena including fission, reaction cross sections, and structure/decay properties is critical for applications ranging from the design new reactors to nonproliferation production radioisotopes diagnosis treatment illness. However, lack a well-quantified, predictive theoretical capability means that most observables must be measured directly used calibrate empirical models, which in turn provide data needed these applications. In many cases, either...
The generation of dynamic high energy density plasmas in the pico- to nano-second time domain at high-energy laser facilities affords unprecedented nuclear science research possibilities. At National Ignition Facility (NIF), primary goal inertial confinement fusion has led synergistic development a unique brightness neutron source, sophisticated diagnostic instrumentation, and versatile experimental platforms. These novel capabilities provide new path investigate processes structural effects...
Lifetimes of states in four the $M1$ bands ${}^{198,199}\mathrm{Pb}$ have been determined through a Doppler-shift attenuation method measurement performed using Gammasphere array. The deduced $B(M1)$ values, which are sensitive probe underlying mechanism for generating these sequences, show remarkable agreement with tilted axis cranking (TAC) calculations. results represent clear evidence new concept nuclear excitations: ``magnetic rotation.''
The lifetime of the 2_+(1) state in 16C has been measured with recoil distance method using 9Be(9Be,2p) fusion-evaporation reaction at a beam energy 40 MeV. mean was to be 11.7(20) ps corresponding B(E2;2_+(1)-->0+) value 4.15(73)e_2 fm_4 [1.73(30) W.u.], consistent other even-even closed shell nuclei. Our result does not support an interpretation for "decoupled" valence neutrons.