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تسجيل مستخدم جديدScalar interaction limits from the beta-neutrino correlation of trapped radioactive atoms
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تأليف
A. Gorelov
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We have set limits on contributions of scalar interactions to nuclear beta decay. A magneto-optical trap (MOT) provides a localized source of atoms suspended in space, so the low-energy recoiling nuclei can freely escape and be detected in coincidence with the beta. This allows reconstruction of the neutrino momentum, and the measurement of the beta-neutrino correlation, in a more direct fashion than previously possible. The beta-neutrino correlation parameter of the 0+ to 0+ pure Fermi decay of 38mK is $tilde{a}$=0.9981+-0.0030+-0.0037, consistent with the standard model prediction a=1.
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