THSDI1
Tech-X, Boulder, Colorado, USA
BNL, Upton, Long Island, New York, USA
Increasing the luminosity of relativistic hadron beams is critical for the advancement of nuclear physics. Coherent electron cooling promises to cool such beams significantly faster than alternative methods. We present simulations of 40 GeV/n Au79+ ions for a single pass, which consists of a modulator, an FEL amplifier and a kicker. In the modulator, the electron beam copropagates with the ion beam, which perturbs the electron beam density and velocity via anisotropic Debye shielding. Self-amplified spontaneous emission lasing in the FEL both amplifies and imparts wavelength-scale modulation on the electron beam perturbations. The modulated electric fields appropriately accelerate or decelerate the copropagating ions in the kicker. In analogy with stochastic cooling, these field strengths are crucial for estimating the effective drag force on the hadrons and, hence, the cooling time. The inherently 3D particle and field dynamics is modeled with the parallel VORPAL framework (modulator and kicker) and with GENESIS (amplifier), with careful coupling between codes. Physical parameters are taken from the CeC proof-of-principle experiment under development at Brookhaven National Lab.
