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Simulating extreme environments using ion and electron beam irradiations for structural materials semiconductor devices and polymers.
Abstract not provided.
Foil focusing effect in pepper-pot measurements in intense electron beams
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Particle-In-Cell Simulations of High Current Density Electron Beams in the Scorpius Linear Induction Accelerator
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Generation of High Emittance Ratios in High Charge Electron Beams at FACET-II
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Generating Sub-Femtosecond Electron Beams at Plasma Wakefield Accelerators
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BLAZED REFLECTION GRATINGS PATTERNED VIA ELECTRON-BEAM LITHOGRAPHY FOR X-RAY SOURCES
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Systems and methods of electron beam induced processing
Embodiments of the present disclosure provide for methods and systems for making structures using an electrospray system while under vacuum. In particular, embodiments of the present disclosure provide for methods and systems for ultra-fast growth of high aspect ratio nano/meso/micro-structures with three dimensional topological complexity and control of phase and composition of the structure formed.
Rapid Electron Beam Modeling at Unprecedented Phase Space Densities
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Record quantum efficiency from superlattice photocathode for spin polarized electron beam production.
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Systems and methods of electron beam induced processing
Embodiments of the present disclosure provide for methods and systems for making structures using an electrospray system while under vacuum. In particular, embodiments of the present disclosure provide for methods and systems for ultra-fast growth of high aspect ratio nano/meso/micro-structures with three dimensional topological complexity and control of phase and composition of the structure formed.
Fiber-Optic Electro-Optic Sensors for Non-Destructive Electron Beam Diagnostics
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Electron Accelerator Technology Innovation: Simulation and Experimental Studies to Advance Applications of High-, Medium-, and Low-Energy Electron Beam Facilities
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ADDITIVE MANUFACTURING OF TITANIUM-ZIRCONIUM-MOLYBDENUM ALLOY USING ELECTRON BEAM POWDER BED FUSION
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Progress in Developing High Energy Nozzle Beams
Electron beam studies of skimmer phenomena and effect on high energy nozzle beam formation
Stopping-power enhancement from discrete particle-wake correlations in high-energy-density plasmas
Three-dimensional (3D) simulations of electron beams propagating in high-energy-density plasmas using the quasistatic Particle-in-Cell (PIC) code QuickPIC demonstrate a significant increase in stopping power when beam electrons mutually interact via their wakes. Each beam electron excites a plasma wave wake of wavelength ~ 2 π c / ω p e , where c is the speed of light and ω p e is the background plasma frequency. Here we show that a discrete collection of electrons undergoes a beam-plasma-like instability caused by mutual particle-wake interactions that causes electrons to bunch in the beam, even for beam densities n b for which fluid theory breaks down. This bunching enhances the beam's stopping power, which we call “correlated stopping,” and the effect increases with the “correlation number” N b ≡ n b ( c / ω p e ) 3 . For example, a beam of monoenergetic 9.7 MeV electrons with N b = 1 / 8 , in a cold background plasma with n e = 10 26 cm – 3 (450 g cm – 3 DT), has a stopping power of 2.28 ± 0.04 times the single-electron value, which increases to 1220 ± 5 for N b = 64 . The beam also experiences transverse filamentation, which eventually limits the stopping enhancement.
Electrostatic hiss and the beam driven electron acoustic instability in the dayside polar cusp
In this study it is shown that the upward moving electron beams observed by DE-1 in the dayside polar cusp at 2 to 5 R sub E drive an electrostatic electron acoustic mode, rather than the whistler mode near resonance, as previously concluded. The characteristics of this instability are compared with the properties of hiss in the polar cusp observed by the Dynamics Explorer (DE-1) satellite. The hiss frequencies and funnel shaped frequency-time spectra are consistent with the electron acoustic mode. However, because the hiss often has a fluctuating magnetic field component near the axis of the funnel shape, the hiss is probably composed of both electron acoustic and whistler mode waves.
Transverse diffusion of electrons in a magnetoplasma
Plasma density and temperature profiles were measured for plasma electrons which were generated by a plasma source and ionization from a 1 kev electron beam. Electron plasma parameters were measured with a cylindrical Langmuir probe which was moved perpendicular to the axis of the beam and field. Electron densities decreased exponentially from the beam center and the decay constant varied with magnetic field in accordance with the Bohm theory of cross field diffusion. This enhanced diffusion effect due to instabilities generated by the electron beam is orders of magnitude larger than that due to particle collisions.