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Efficient propagation of the polarization from laser photons to positrons through Compton scattering and electron-positron pair creation

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 نشر من قبل Tsunehiko Omori
 تاريخ النشر 2005
  مجال البحث فيزياء
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We demonstrated for the first time the production of highly polarized short-pulse positrons with a finite energy spread in accordance with a new scheme that consists of two-quantum processes, such as inverse Compton scatterings and electron-positron pair creations. Using a circularly polarized laser beam of 532 nm scattered off a high-quality electron beam with the energy of 1.28 GeV, we obtained polarized positrons with an intensity of 10^4 e+/bunch. Magnitude of positron polarizations was determined as 73+-15(sta) +-19(sys)% by means of a newly designed positron polarimeter.



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