Simulation Package for Parallel 3D Modeling of an Electron Gun with a Diamond Amplifier

The Relativistic Heavy Ion Collider (RHIC) contributes fundamental advances to nuclear physics by colliding a wide range of ions. A novel electron cooling section, a key component of the proposed RHIC luminosity upgrade, requires the acceleration of high-charge electron bunches with low emittance and energy spread. A promising candidate for the electron source is the recently developed concept of a high quantum efficiency photoinjector with a diamond amplifier. However, no code is available to use for investigating such a photoinjector via computer simulations. This project will develop numerical algorithms for the generation and transport of secondary electrons through diamond amplifiers in strong electric fields. These algorithms will be implemented in an existing parallel three-dimensional (3D) particle-in-cell (PIC) code and then tested against experimental data. Phase I implemented Monte Carlo models for the generation and transport of secondary electrons in diamond. The simulation results were in agreement with published data on the number of secondary electrons generated over time. It also was demonstrated that the code can be effectively used to simulate an electron gun of interest to RHIC. Phase II will implement additional code to model inelastic scattering from phonons and impurities, and electron emission from diamond surfaces with negative affinity layers. The simulation results will be verified with published theoretical/computational results and validated with available experimental data. Commercial Applications and Other Benefits as described by the awardee: A code for simulating diamond amplifiers in electron photo injectors should directly benefit scientists working to design high-current electron accelerators required for cooling high-energy ion beams at the RHIC. These capabilities will also benefit an existing PIC code that is already commercially distributed, thus increasing its potential for generating further commercial revenue.