Comparison of electron cloud mitigating coatings using retarding field analyzers

Simulation of the Electron Flux into the Main Injector Electron Cloud Retarding Field Analyzer Using Vorpal

We present results from precision simulations of the electron cloud (EC) in the Fermilab Main Injector (MI), focusing on the dynamics of the EC close to the Retarding Field Analyzer (RFA) detectors. Our simulations are based on the Vorpal plasma simulation package. We find that the presence of a parasitic, weak (few Gauss) magnetic field significantly alters the spatial distribution of electron...

Secondary electron yield measurements from thin surface coatings for NLC electron cloud reduction

In the beam pipe of the positron damping ring of the Next Linear Collider, electrons will be created by beam interaction with the surrounding vacuum chamber wall and give rise to an electron cloud. Several solutions are possible for avoiding the electron cloud, without changing the bunch structure or the diameter of the vacuum chamber. Some of the currently available solutions for preventing th...

Mems-enabled Retarding Potential Analyzers for Hypersonic In-flight Plasma Diagnostics

We report the design, fabrication, and preliminary characterization of a microfabricated retarding potential analyzer (RPA) that ensures unprecedented grid alignment accuracy. Through refined manufacturing methods, improved tolerances upon assembly serve to increase the signal to noise ratio (SNR). Furthermore, microfabrication permits smaller features overcoming sensor limitations previously b...

A Retarding Field Energy Analyser for the JET Plasma Boundary . A Retarding Field Energy Analyser for the JET Plasma Boundary

Methods for Quantitative Interpretation of Retarding Field Analyzer Data∗

A great deal of Retarding Field Analyzer (RFA) data has been taken as part of the CesrTA program at Cornell. Obtaining a quantitative understanding of this data requires use of cloud simulation programs, as well as a detailed model of the RFA itself. In a drift region, the RFA can be modeled by postprocessing the output of a simulation code, and one can obtain best fit values for important simu...