Emittance, surface structure, and electron emission

Emittance of a field emission electron source

An analytical formula of the emittance of a field emitter is given. In contrast to thermal and photoemission, such a formula contains complexity due to the multidimensional nature of the source. A formulation of emittance is given for oneand three-dimensional 3D field emitters. The 3D formulation makes use of the point charge model of a unit cell emitter coupled with a trajectory analysis to fo...

Low Emittance Thermionic Electron Guns*

Emittance and entropy of electron beams

Creating high-brightness electron beams, which have many practical applications, is done with cathodes in regions with large electric field by field emission. The brightness is high when the current is high and the volume of the beam in phase space is small. An estimate of the phase space volume is the rms emittance. The simulations described in this report show that the beam emitted by a gated...

Electron Cloud at Low Emittance in Cesrta*

The Cornell Electron Storage Ring (CESR) has been reconfigured as a test accelerator (CesrTA) for a program of electron cloud (EC) research at ultra low emittance. The instrumentation in the ring has been upgraded with local diagnostics for measurement of cloud density and with improved beam diagnostics for the characterization of both the low emittance performance and the beam dynamics of high...

Nano-Structure Roughening on Poly(Lactic Acid)PLA Substrates: Scanning Electron Microscopy (SEM) Surface Morphology Characterization

Scanningelectron microscopy (SEM) has been utilized  to examine  the morphology and topography alterations  in the surface of Poly(Lactic Acid)(PLA) fabrics due to UV/Ozoneirradiation. In the past decade, a growing attention in the usage of “Green Techniques” in industrial applications has been observed owing to many benefits such as low impurities and their relatively low cost to substitute th...