Observation of polarized positrons from an undulator-based source.
نویسندگان
چکیده
An experiment (E166) at the Stanford Linear Accelerator Center has demonstrated a scheme in which a multi-GeV electron beam passed through a helical undulator to generate multi-MeV, circularly polarized photons which were then converted in a thin target to produce positrons (and electrons) with longitudinal polarization above 80% at 6 MeV. The results are in agreement with GEANT4 simulations that include the dominant polarization-dependent interactions of electrons, positrons, and photons in matter.
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ورودعنوان ژورنال:
- Physical review letters
دوره 100 21 شماره
صفحات -
تاریخ انتشار 2008