A5101834802- Laser-Plasma Interactions and Diagnostics
- Nuclear Physics and Applications
- Neutrino Physics Research
- Astrophysics and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Radiation Detection and Scintillator Technologies
- High-pressure geophysics and materials
- Laser-Matter Interactions and Applications
- Magnetic confinement fusion research
- Atomic and Subatomic Physics Research
- Nuclear reactor physics and engineering
- Pulsed Power Technology Applications
- Particle Detector Development and Performance
- Laser-induced spectroscopy and plasma
- X-ray Spectroscopy and Fluorescence Analysis
- Atomic and Molecular Physics
- Particle physics theoretical and experimental studies
- Particle Accelerators and Free-Electron Lasers
- Fusion materials and technologies
- Dark Matter and Cosmic Phenomena
- Particle accelerators and beam dynamics
- Laser Design and Applications
- Ion-surface interactions and analysis
- Advanced X-ray Imaging Techniques
- Gyrotron and Vacuum Electronics Research
Sandia National Laboratories
2008-2024
Yale University
2022-2023
The Ohio State University
2019-2023
Université Libre de Bruxelles
2023
Chiba University
2023
University of Kansas
2023
Uppsala University
2022
University of Almería
2019
Universidad de Lima
2019
Massachusetts Institute of Technology
2018
Here Z, a 60 TW/5 MJ electrical accelerator located at Sandia National Laboratories, has been used to implode tungsten wire-array Z pinches. These arrays consisted of large numbers wires (120–300) with wire diameters 7.5 15 μm placed in symmetric cylindrical array. The experiments array ranging from 1.75 4 cm and lengths 1 2 cm. A long, diam consisting 240, (4.1 mg mass) achieved an x-ray power ∼200 TW energy nearly MJ. Spectral data suggest optically thick, Planckian-like radiator below...
This article presents the design of Radio Neutrino Observatory Greenland (RNO-G) and discusses its scientific prospects. Using an array radio sensors, RNO-G seeks to measure neutrinos above 10 PeV by exploiting Askaryan effect in neutrino-induced cascades ice. We discuss experimental considerations that drive RNO-G, present first measurements hardware is be deployed projected sensitivity instrument. will production-scale detector for in-ice neutrino signals.
We present observations for 20-MA wire-array z pinches of an extended wire ablation period 57%+/-3% the stagnation time array and non-thin-shell implosion trajectories. These experiments were performed with 20-mm-diam arrays used double- -pinch inertial confinement fusion [M. E. Cuneo, Phys. Rev. Lett. 88, 215004 (2002)] on Z accelerator [R. B. Spielman, Plasmas 5, 2105 (1998)]. This has smallest wire-wire gaps typically at 20 MA (209 microm ). The this indicates that two-dimensional (r-z)...
Abstract is a Monte Carlo framework designed to simulate ultra-high energy neutrino detectors that rely on the radio detection method. This method exploits emission generated in electromagnetic component of particle shower following interaction. simulates everything from interaction medium, subsequent Askaryan emission, propagation signal detector and finally response. as modern, modular Python-based framework, combining flexibility design with user-friendliness. It includes state-of-the-art...
The Askaryan Radio Array (ARA) is an ultra-high energy (UHE, $>10^{17}$ eV) neutrino detector designed to observe neutrinos by searching for the radio waves emitted relativistic products of neutrino-nucleon interactions in Antarctic ice. In this paper, we present constraints on diffuse flux between $10^{16}-10^{21}$ eV resulting from a search two complementary analyses, both analyzing four years data (2013-2016) deep stations (A2, A3) operating at that time. We place 90 % CL upper limit all...
Abstract Since summer 2021, the Radio Neutrino Observatory in Greenland (RNO-G) is searching for astrophysical neutrinos at energies $${>10}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mo>></mml:mo> <mml:mn>10</mml:mn> </mml:mrow> </mml:math> PeV by detecting radio emission from particle showers ice around Summit Station, Greenland. We present an extensive simulation study that shows how RNO-G will be able to measure energy of such cascades, which turn...
Tungsten wire array implosions on the 7- to 8-MA Saturn generator have been optimized using number and diameter variations produce $75\ifmmode\pm\else\textpm\fi{}10\mathrm{TW}$ of x rays with total energy outputs $450\ifmmode\pm\else\textpm\fi{}50\mathrm{kJ}.$ By increasing wires in a 12.5-mm-diam from 24 70 simultaneously decreasing individual 13 7.5 \ensuremath{\mu}m, radiated power increased $20\ifmmode\pm\else\textpm\fi{}3$ $40\ifmmode\pm\else\textpm\fi{}6\mathrm{TW}$ x-ray pulse width...
We have measured the x-ray power and energy radiated by a tungsten-wire-array z pinch as function of peak current width anode-cathode gap at base pinch. The measurements were performed 13- 19-MA currents 1-, 2-, 3-, 4-mm gaps. wire material, number wires, wire-array diameter, length, wire-array-electrode design, normalized-pinch-current time history, implosion time, diagnostic package held constant for experiments. To keep constant, mass array was increased I2 (i.e., diameter each I), where...
The Radar Echo Telescope for Cosmic Rays (RET-CR) is a recently funded experiment designed to detect the englacial cascade of cosmic ray-initiated air shower via in-ice radar, toward goal full-scale, next-generation ultrahigh energy neutrinos in polar ice. For rays with primary greater than 10 PeV, roughly 10% an shower's reaches surface high elevation ice sheet ($\ensuremath{\gtrsim}2\text{ }\text{ }\stackrel{\ifmmode \dot{}\else \textperiodcentered \fi{}}{\mathrm{k}}\mathrm{m}$)...
In the concept of dynamic hohlraum an imploding Z pinch is optically thick to its own radiation. Radiation may be trapped inside give a radiation temperature greater than that outside pinch. The typically produced by colliding outer Z-pinch liner onto inner liner. collision generates strongly radiating shock, and As implosion continues after collision, continue increase due ongoing PdV (pressure times change in volume) work done implosion. principal, point at which burns through, becomes...
Filtered x-ray diode (XRD) detectors are used as primary radiation flux diagnostics on Sandia’s Z accelerator, which generates nominally a 200-TW, 2-MJ, pulse. Given such levels and XRD sensitivities the being fielded 23 m from source. The standard diagnostic setup discussed. Vitreous carbon photocathodes to reduce effect of hydrocarbon contamination present in Z-machine vacuum system. Nevertheless pre- postcalibration data taken indicate spectrally dependent changes sensitivity these by up...
Initial experiments to study the Z-pinch-driven hohlraum high-yield inertial confinement fusion (ICF) concept of Hammer, Tabak, and Porter [Hammer et al., Phys. Plasmas 6, 2129 (1999)] are described. The relationship between measured pinch power, temperature, secondary coupling (“hohlraum energetics”) is well understood from zero-dimensional semianalytic, two-dimensional view factor radiation magnetohydrodynamics models. These have shown highest x-ray powers coupled any (26±5 TW), indicating...
A dynamic hohlraum is formed when an imploding annular cylindrical Z-pinch driven plasma collides with internal low density convertor. This collision generates inward traveling shock wave that emits x rays, which are trapped by the optically thick and can be used to drive inertial fusion capsule embedded in scheme has potential efficiently high yield capsules due close coupling between intense radiation generation capsule. In prior experiments [J. E. Bailey et al., Phys. Rev Lett. 89, 095004...
The radiation and shock generated by impact of an annular tungsten $Z$-pinch plasma on a 10-mm diam $5\mathrm{\text{\ensuremath{-}}}\mathrm{m}\mathrm{g}/\mathrm{c}\mathrm{c}$ $\mathrm{C}{\mathrm{H}}_{\mathrm{2}}$ foam are diagnosed with x-ray imaging power measurements. radiative was virtually unaffected instabilities. 5-ns-duration $\ensuremath{\sim}135\mathrm{\text{\ensuremath{-}}}\mathrm{e}\mathrm{V}$ field imploded 2.1-mm-diam CH capsule. measured temperature, radius, capsule radius...
Present-day Z-pinch experiments generate 200 TW peak power, 5–10 ns duration x-ray bursts that provide new possibilities to advance radiation science. The support both the underlying atomic and plasma physics, as well inertial confinement fusion astrophysics applications. A typical configuration consists of a sample located 1–10 cm away from pinch, where it is heated 10–100 eV temperatures by pinch radiation. spectrally-resolved sample-plasma absorption measured aiming spectrographs through...
We report the observation of radar echoes from ionization trails high-energy particle cascades. Data were taken at SLAC National Accelerator Laboratory, where full electron beam (∼10^{9} e^{-} ∼10 GeV/e^{-}) was directed into a plastic target to simulate an ultrahigh-energy neutrino interaction. The interrogated with radio waves, and coherent reflections cascades detected properties consistent theoretical expectations. This is first definitive cascades, which may lead viable detection...
A double Z pinch driving a cylindrical secondary hohlraum from each end has been developed which can indirectly drive intertial confinement fusion capsule implosions with time-averaged radiation fields uniform to 2%-4%. 2D time-dependent view factor and hydrodynamic simulations using the measured primary temperatures show that convergence ratios of at least 10 average distortions sphericity <Delta r>/r<or=30% are possible on accelerator may meet symmetry requirements for scaling yields >200 MJ.
Three hohlraum concepts are being pursued at Sandia National Laboratories (SNL) to investigate the possibility of using pulsed power driven magnetic implosions (Z pinches) drive targets capable fusion yields in range 200-1000 MJ. This research is conducted on SNL's Z facility, which driving peak currents 20 MA various pinch load configurations that produce implosion velocities as high 7.5 × 107cm/s, X ray energies 1-2 MJ and powers 100-250 TW. The first concept, denoted dynamic hohlraum, has...
Abstract: In this special section, educators describe current approaches to teaching theatre. Drawing from their experiences in K–12, community theatre, and higher education contexts, seventeen theatre explain pedagogical responses the COVID-19 pandemic, administrative cutbacks, campus issues, generative AI, accessibility, consent, students’ fear of taking risks. These short pieces also provide new ways considering assessment, history performance theory, engaging non-majors studies. This...
Detailed quantum-chemistry calculations of field-induced fragmentation reactions ionic liquid are presented. The simulations identified the most likely channels for hard (breaking covalent bonds) fragmentation. computed energetics and soft clusters into moieties) can be incorporated in multiscale models thrusters’ operation. determined that occurs on a picosecond scale, revealing these large flexible ions heated when accelerated by electric field. Although acquired internal kinetic energy...
The 100 ns, 20 MA pinch-driver Z is surrounded by an extensive set of diagnostics. There are nine radial lines sight at 12° above horizontal and each these may be equipped with up to five diagnostic ports. Instruments routinely fielded viewing the pinch from side ports include x-ray diode arrays, photoconducting detector bolometers, transmission grating spectrometers, time-resolved pinhole cameras, crystal calorimeters, silicon photodiodes, neutron detectors. A package on axis for internal...
We have developed wire-array z -pinch scaling relations for plasma-physics and inertial-confinement-fusion (ICF) experiments. The can be applied to the design of accelerators high-fusion-yield (approximately 0.4 GJ/shot) inertial-fusion-energy 3 research. find that (delta(a)/delta(RT)) proportional (m/l)1/4 (Rgamma)(-1/2), where delta(a) is imploding-sheath thickness a wire-ablation-dominated pinch, delta(RT) sheath Rayleigh-Taylor-dominated m total mass, l axial length array, R initial...
In the pursuit of measurement still-elusive ultrahigh-energy (UHE) neutrino flux at energies order EeV, detectors using in-ice Askaryan radio technique have increasingly targeted lower trigger thresholds. This has led to improved trigger-level sensitivity UHE neutrinos. Working with data collected by Radio Array (ARA), we search for candidates lowest threshold achieved date, leading analysis-level sensitivities. A on a set 208.7~days livetime from reduced-threshold fifth ARA station is...
Over the last 25 years, radiowave detection of neutrino-generated signals, using cold polar ice as neutrino target, has emerged perhaps most promising technique for extragalactic ultra-high energy neutrinos (corresponding to energies in excess 0.01 Joules, or $10^{17}$ electron volts). During summer 2021 and tandem with initial deployment Radio Neutrino Observatory Greenland (RNO-G), we conducted radioglaciological measurements at Summit Station, refine our understanding target. We report...