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Determination of the Axial-Vector Weak Coupling Constant with Ultracold Neutrons

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 نشر من قبل Jianglai Liu
 تاريخ النشر 2010
  مجال البحث
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A precise measurement of the neutron decay $beta$-asymmetry $A_0$ has been carried out using polarized ultracold neutrons (UCN) from the pulsed spallation UCN source at the Los Alamos Neutron Science Center (LANSCE). Combining data obtained in 2008 and 2009, we report $A_0 = -0.11966 pm 0.00089_{-0.00140}^{+0.00123}$, from which we determine the ratio of the axial-vector to vector weak coupling of the nucleon $g_A/g_V = -1.27590_{-0.00445}^{+0.00409}$.



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