Designing a Coherent Electron Cooling System for High-Energy Hadron Colliders

The electron cooler for the proposed luminosity upgrade of the Relativistic Heavy Ion Collider (RHIC) represents a significant design challenge due to the high energy of the ion beam. An exciting concept known as ¿coherent¿ electron cooling (CEC) combines the best features of electron cooling and stochastic cooling, via free-electron laser (FEL) technology, to offer the possibility of cooling high-energy hadron beams with order-of-magnitude shorter cooling times. However, the CEC concept is unproven and requires detailed simulation of its key components. In this project, the parallel VORPAL framework, which has successfully simulated the underlying physics of conventional electron cooling sections, will be used to simulate relevant aspects of the CEC concept for enhanced cooling of heavy ion beams. Phase I will involve the simulation of the ¿modulator¿ of a CEC section, in which ions imprint a signature (i.e., wake) on the electron density and velocities. Then, linear one-dimensional FEL theory and other simplified assumptions will be used to propagate the ions and electrons to the ¿kicker¿, where an amplified and phase-shifted electron wake will be used to strongly reduce the thermal motion of the ions that originally generated the wake. Commercial Applications and other Benefits as described by the awardee: In addition to the application to the RHIC upgrade, the study should further enhance the parallel three-dimensioal VORPAL framework, which is already a successful commercial product.