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Title: The PEPPo method for polarized positrons and PEPPo II

The Polarized Electrons for Polarized Positrons (PEPPo) experiment at the injector of the Continuous Electron Beam Accelerator Facility demonstrated for the first time the efficient transfer of polarization from electrons to positrons via a two-step process: polarized bremsstrahlung radiation is induced by a polarized electron beam in a high-Z target; then the polarized bremsstrahlung produces polarized positrons via the pair-production process in the same target. Positron polarization up to 82% was measured for an initial electron beam momentum of 8.19 MeV/c, limited only by the electron beam polarization of 85%. This technique extends polarized positron capabilities from GeV to MeV electron beams, and opens access to polarized positron beam physics to a wide community. We present the results of the PEPPo experiment and outline tentative plans for a follow-up experiment that would investigate key aspects of an approach based on PEPPo as a polarized positron source for the 12 GeV Upgrade of CEBAF.
  1. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
Publication Date:
Report Number(s):
JLAB-PHY-18-2632; DOE/OR/23177-4331
Journal ID: 0094-243X
Grant/Contract Number:
Accepted Manuscript
Journal Name:
AIP Conference Proceedings
Additional Journal Information:
Journal Volume: 1970; Journal Issue: 1; Conference: JPOS17,12-15 Sep 2017. Newport News, VA, USA
Research Org:
Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
Contributing Orgs:
for the PEPPo Collaboration
Country of Publication:
United States
43 PARTICLE ACCELERATORS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; Leptons; International science organizations; Photon scattering; Electromagnetic radiation; Particle beams
OSTI Identifier: