Simulations of Positron Capture at Ce+BAF

Conference · 01 June 2024

DOI:https://doi.org/10.18429/JACoW-IPAC2024-MOPC54· OSTI ID:2372855

Ushakov, Andriy ^[1]; Benesch, Jay ^[1]; Grames, Joseph ^[1]; Nagaitsev, Sergei ^[2]; Raut, Nabin ^[1]; Rimmer, Robert ^[1]; Roblin, Yves ^[1]; Voutier, Eric ^[3]; Wang, Shaoheng ^[1]

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1. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
2. Brookhaven National Laboratory (BNL), Upton, NY (United States)
3. Univ. Paris-Saclay, Gif-sur-Yvette (France)

We present a capture concept for the continuous wave (CW) polarized positron injector for the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab (Ce+BAF). This two-step concept is based on (1) the generation of bremsstrahlung radiation by a longitudinally polarized electron beam 1 mA, 120 MeV, 90% polarization), passing through a tungsten target, and (2) the production of e+e--pairs by these bremsstrahlung photons in the same target. To provide highly-polarized positron beams (>60% polarization) or high-current positron beams (>1 µA) with low polarization for nuclear physics experiments, the positron source requires a flexible capture system with an adjustable energy selection band. The results of beam dynamics simulations and calculations of the power deposited in the positron capture section are presented.

• Research Organization: Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Brookhaven National Laboratory (BNL), Upton, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP)
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 2372855
• Report Number(s): JLAB-ACC-24-4037; DOE/OR/23177-7469
• Country of Publication: United States
• Language: English