Speaker
Description
Positron beams are considered as a new capability for the CEBAF 12 GeV accelerator at Jefferson Lab. This capability would provide a unique facility for hadronic physics experiments and tests of the Standard Model. Secondary e+/e- particle beams are created using the polarized bremsstrahlung of an intense continuous-wave (CW) spin polarized primary electron beam. To do this, the existing Low Energy Research Facility is re-imagined with a new 300 kV dc HV GaAs photogun which provides an intense ~1 mA and highly polarized ~90% electron beam. This beam is accelerated to ~100 kW and directed to a rotating W-target, where secondary e+ (or e-) are collected to a CW beam, accelerated to 123 MeV and injected to CEBAF for energies up to 12 GeV. This new Ce+BAF configuration is optimized to provide experiments with positron spin polarization >60% and intensity greater than >50 nA, and greater intensities when high spin polarization is not required.
