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تسجيل مستخدم جديدUltrahigh-density spin-polarized H and D observed via magnetization quantum beats
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We measure nuclear and electron spin-polarized H and D densities of at least 10$^{19}, cm^{-3}$ with $sim$10 ns lifetimes, from the photodissociation of HBr and DI with circularly-polarized UV light pulses. This density is $sim$6 orders of magnitude higher than that produced by conventional continuous-production methods, and, surprisingly, at least 100 times higher than expected densities for this photodissociation method. We observe the hyperfine quantum beating of the H and D magnetization with a pick-up coil, i.e., the respective 0.7 and 3 ns periodic transfer of polarization from the electrons to the nuclei and back. The $rm{10^{19},cm^{-3}}$ spin-polarized H and D density is sufficient for laser-driven ion acceleration of spin polarized electrons, protons, or deuterons, the preparation of nuclear-spin-polarized molecules, and for the demonstration of spin-polarized D-T or D-$rm{{^3He}}$ laser fusion, for which a reactivity enhancement of $rm{sim50%}$ is expected.
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