Conveners
Polarized Electron Sources II
- Joe Grames (JLab)
The European Workshop on Photocathodes for Acclerator Applications (EWPAA 2024) took place in Dresden, Germany.
A summary of cathode work in Europe concerning photocathodes for spin-polarized electron beams will be presented. Topics include ,e.g., high QE cathodes for driving spin polarized positron sources for applied science, mechanisms to increase cathode lifetime and materials....
GaAs-based photocathodes are currently the only viable technology for producing a spin-polarized electron beam at a high enough average current required for particle collider based nuclear and high energy physics experiments. In this work we give an overview on research carried out at Cornell University focused on improving the robustness of GaAs based photocathodes, including: the development...
Strained superlattices of GaAs/GaAsP grown using molecular beam epitaxy (MBE) have been used for more than 20 years to generate high polarization electron beams for nuclear physics. GaAs/GaAsP superlattices have several manufacturing challenges, including the thick graded layer required for the virtual GaAsP substrate, the significant difference in optimal growth temperatures for GaAs and...
Photocathodes capable of producing highly spin polarized electrons beams are required for both high energy and nuclear physics experiments. In this talk, we report on the commissioning of a new UHV vacuum system for photocathode characterization, which includes a retarding field Mott polarimeter for the measurement of electron spin polarization. We will illustrate the design of III-Vs...
Electron sources capable of high polarization and quantum efficiency (QE) are critical to the operation of electron accelerators such as the Continuous Electron Beam Accelerator Facility (CEBAF) at Thomas Jefferson National Accelerator Facility. Strained superlattice photocathodes containing pairs of strained GaAs/GaAsP are currently the standard for beam production at CEBAF, capable of more...
