Simulations of Electron Cooling for a Polarized Electron-Ion Collider Design

Relativistic magnetized electron cooling is essential for achieving the ion beam luminosity requirements of proposed electron-ion collider (EIC) designs. Because the cooling system will have to operate in previously untested parameter regimes, accurate calculations of magnetized dynamic friction are required at the design stage. In particular, one has to include all relevant physics that might increase the cooling time, such as space charge forces, field errors and complicated phase space distributions of imperfectly magnetized electron beams. We present simulations relevant to the JLEIC design, performed with the BETACOOL and JSPEC codes, as well as RadiaSoft's Sirepo interface to JLEIC. We also present recent work on a new semi-analytic treatment of momentum transfer from a single magnetized electron to a drifting ion, and its use for calculations of dynamic friction.