A5057020444- Laser-Plasma Interactions and Diagnostics
- Nuclear Physics and Applications
- Magnetic confinement fusion research
- High-pressure geophysics and materials
- Laser-induced spectroscopy and plasma
- Ion-surface interactions and analysis
- Solar and Space Plasma Dynamics
- Fusion materials and technologies
- Gamma-ray bursts and supernovae
- Astro and Planetary Science
- Radiation Detection and Scintillator Technologies
- Atomic and Subatomic Physics Research
- Combustion and Detonation Processes
- Cold Fusion and Nuclear Reactions
- Diamond and Carbon-based Materials Research
- Radiation Therapy and Dosimetry
- Astronomy and Astrophysical Research
- Ionosphere and magnetosphere dynamics
- Space Satellite Systems and Control
- Iron oxide chemistry and applications
- Particle Detector Development and Performance
- Geomagnetism and Paleomagnetism Studies
- Particle Accelerators and Free-Electron Lasers
- Spectroscopy and Laser Applications
- Computational Fluid Dynamics and Aerodynamics
Massachusetts Institute of Technology
2021-2025
Fusion Academy
2021-2025
Plasma Technology (United States)
2021-2025
Fusion (United States)
2024
Los Alamos National Laboratory
2018
The Particle Time of Flight (PTOF) diagnostic is a chemical vapor deposition diamond-based detector and the only for measuring nuclear bang times low yield (<1013) shots on National Ignition Facility. Recently, comprehensive study impulse responses revealed certain detectors with very fast consistent rise time <50 ps, enabling burn history measurements. At current standoff 50 cm, this measurement possible 14 MeV neutrons from deuterium–tritium (DT) fusion plasmas. PTOF-inferred...
Magnetizing a cryogenic deuterium–tritium (DT)-layered inertial confinement fusion (ICF) implosion can improve performance by reducing thermal conduction and improving DT-alpha in the hot spot. A room-temperature, magnetized indirect-drive ICF platform at National Ignition Facility has been developed, using high-Z, high-resistivity AuTa4 alloy as hohlraum wall material. Experiments show 2.5× increase deuterium–deuterium (DD) neutron yield 0.8-keV hot-spot temperature with application of 12-T...
Magnetic reconnection is a ubiquitous and fundamental process in plasmas by which magnetic fields change their topology release energy. Despite decades of research, the physics governing many parameter regimes remains controversial. Contemporary theories predict that long, narrow current sheets are susceptible to tearing instability split into isolated islands (or plasmoids), resulting an enhanced rate. While several experimental observations plasmoids regime low-to-intermediate...
This study investigated discrepancies between measured and simulated x-ray drive in Inertial Confinement Fusion (ICF) hohlraums at the National Ignition Facility (NIF). Despite advances radiation-hydrodynamic simulations, a consistent "drive deficit" remains. Experimentally ICF capsule bang-times are systematically 400-700 ps later than simulations predict. The Build-A-Hohlraum (BAH) campaign explored potential causes for this discrepancy by varying hohlraum features, including laser...
Here, we present a Monte Carlo toolkit for validating step range filter (SRF) spectrometer designs. Geant4 is used to transport charged particles through the SRF filters generate synthetic data that include realistic CR-39 effects. Synthetic spectra generated by this method inherently account instrument response and allow quantification of performance before shots. The usefulness demonstrated its application number problems. A new broadband ∼10 MeV wide 3He3He proton spectrum validated, an...
State of the art experiments show that Biermann-battery magnetic fields in laser-driven plasmas can produce a magnetized collisionless shock precursor, mimicking scenario Venus bow-shock formation.
A targeted experiment at the National Ignition Facility (NIF) confirms presence of multispecies hydrodynamics in inertial confinement fusion hohlraums relevant to ignition. The effects are identified by filling gold hohlraum with a deuterium-tritium (DT) gas mixture instead helium. As is heated NIF lasers, it implodes inward, compressing and heating DT, which leads fusion. resulting DT-fusion neutrons measured space, time, yield, angle, energy. distinct, peaked, triangular shape radial...
This study investigated discrepancies between measured and simulated x-ray drive in Indirect-Drive Inertial Confinement Fusion (ID-ICF) hohlraums at the National Ignition Facility. Despite advances radiation-hydrodynamic simulations, a consistent “drive deficit” remains. Experimentally ID-ICF capsule bang-times are systematically 400–700 ps later than simulations predict. The Build-A-Hohlraum (BAH) campaign explored potential causes for this discrepancy by varying hohlraum features,...
A more complete understanding of laser-driven hohlraum plasmas is critical for the continued development and improvement ICF experiments. In these hohlraums, self-generated electric magnetic fields can play an important role in modifying plasma properties such as heat transport; however, strength distribution electromagnetic hohlraums remain largely uncertain. To explore this question, we conducted experiments at OMEGA laser facility, using monoenergetic proton radiography to probe vacuum...
The Particle Time of Flight (PTOF) detector is a chemical vapor deposition diamond-based used to measure bang times in low-yield (≲ 1015 neutrons) experiments at the National Ignition Facility (NIF) Lawrence Livermore Laboratory (LLNL). Historically, impulse response for PTOF diamond detectors has been obtained from x-ray timing shots on NIF and MegaRay pulsed electron accelerator LLNL. may alternatively be using single particle interactions with detector, substantially less cost higher...
With the advent of ignited plasmas at National Ignition Facility (NIF), alpha physics has become a driving factor in theoretical understanding and experimental behavior. In this communication, we explore aspects direct alpha-ion heating through comparison consequences from one-fluid two-fluid models hydrodynamic approach. We show that case with all energy deposited electrons raises ignition criteria by ∼4 keV or ∼0.2 g/cm2 hotspot relative to ions. recently NIF implosion, 30% 3.5 MeV α is...
Penumbral imaging is a technique used in plasma diagnostics which radiation source shines through one or more large apertures onto detector. To interpret penumbral image, must reconstruct it to recover the original source. The inferred always has some error due noise image and uncertainty instrument geometry. Interpreting thus requires quantification of that inference’s uncertainty. Markov chain Monte Carlo algorithms have been quantify for similar problems but never inference shape an...
Proton radiography is an essential diagnostic for studying magnetic fields in high energy density physics experiments. Protons are born a fusion implosion, traverse the plasma, and detected on CR-39 solid state nuclear track detectors. Here, it shown that there intrinsic non-uniformity ∼15 MeV D3He proton data. The increasing angle between trajectory center of detector results traveling through more stack material. As protons travel material lose energy, spectrum gets wider. at lower end can...
Image plates (IPs), or phosphor storage screens, are a technology employed frequently in inertial confinement fusion (ICF) and high energy density plasma (HEDP) diagnostics because of their sensitivity to many types radiation, including, x rays, protons, alphas, beta particles, neutrons. Prior studies characterizing IPs predicated on the signal level remaining below scanner saturation threshold. Since scanning process removes some from IP via photostimulated luminescence, repeatedly an can...
Image plates (IPs) are a quickly recoverable and reusable radiation detector often used to measure proton x-ray fluence in laser-driven experiments. Recently, IPs have been radiography stack on the OMEGA laser, diagnostic historically implemented with CR-39, or radiochromic film. The this other diagnostics detect charged particles, neutrons, x-rays indiscriminately. using photo-stimulated luminescence (PSL) material, phosphor, which electrons excited metastable states by ionizing radiation....
This paper reports on investigations the impact of higher neutron fluences detection efficiency protons with CR-39, a charged particle track detector. CR-39 is widely used as diagnostic for inertial fusion applications and an integral component numerous diagnostics at OMEGA laser facility National Ignition Facility. As experiments continue to produce yields, existing are impacted by than they were originally designed for. presents data from measuring proton signal pieces different levels...
To benchmark the accuracy of models and improve predictive capability future experiments, National Ignition Facility requires measurements physical conditions inside inertial confinement fusion hohlraums. The ion temperature bulk motion velocity gas-filled regions hohlraum can be obtained by replacing helium tamping gas in with deuterium-tritium (DT) measuring Doppler broadening shift neutron spectrum produced nuclear reactions hohlraum. understand spatial distribution production hohlraum,...
New designs and a new analysis technique have been developed for an existing compact charged-particle spectrometer on the NIF OMEGA. The extends capabilities of this diagnostic to measure arbitrarily shaped ion spectra down 1 MeV with yields as low 106. Three different are provided optimized measurement DD protons, T3He deuterons, 3He3He protons. highly customizable, generalized framework is optimizing design alternative applications. Additionally, understanding detector’s response...
Charged particle spectrometry is a critical diagnostic to study inertial-confinement-fusion plasmas and high energy density plasmas. The OMEGA Laser Facility has two fixed magnetic charged spectrometers (CPSs) measure MeV-ions. In situ calibration of these was carried out using 241Am 226Ra alpha emitters. emission spectrum from the sources measured independently surface-barrier detectors (SBDs). dispersion broadening CPS systems were determined by comparing that SBD. method significantly...
The Particle Time of Flight (PTOF) diagnostic is a chemical vapor deposition diamond detector used for measuring multiple nuclear bang times at the National Ignition Facility. Due to non-trivial, polycrystalline structure these detectors, individual characterization and measurement are required interrogate sensitivity behavior charge carriers. In this paper, process developed determining x-ray PTOF detectors relating it intrinsic properties detector. We demonstrate that sample measured has...
Radiochromic film (RCF) and image plates (IPs) are both commonly used detectors in diagnostics fielded at inertial confinement fusion (ICF) high-energy-density physics (HEDP) research facilities. Due to the intense x-ray background all ICF/HEDP experiments, accurately calibrating optical density of RCF as a function dose, photostimulated luminescence per photon IPs energy, is necessary for interpreting experimental results. Various measurements sensitivity curve different x rays have been...
Inertial Confinement Fusion and Magnetic (ICF MCF) follow different paths toward goals that are largely common. In this paper, the claim is made progress can be accelerated by learning from each other across two fields. Examples of successful cross-community knowledge transfer presented highlight gains working together, specifically in areas high-resolution x-ray imaging spectroscopy neutron spectrometry. Opportunities for near- mid-term collaboration identified, including chemical vapor...
This letter reports the first complete observation of magnetized collisionless shock precursors formed through compression Biermann-battery magnetic fields in laser produced plasmas. At OMEGA, lasers produce a supersonic CH plasma flow which is with fields. The collides an unmagnetized hydrogen gas jet to create precursor. situation where flowing carries field similar Venusian bow shock. Imaging 2$\omega$ Thomson scattering confirms that interaction and shows density temperature jumps....
CR-39 proton radiography is an experimental charged-particle backlighter platform fielded and used at OMEGA the NIF to image electric magnetic fields in a subject plasma. Processing piece of involves etching it hot NaOH, etch time can greatly impact background-to-signal ratio (BSR) low-fluence (≲4 × 104 cm−2) regions detection efficiency high-fluence (≳7 105 cm−2). For data with high fluence variation, these effects mean that any single will result ≳15% error measured signal either high- or...