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تسجيل مستخدم جديدA solenoidal electron spectrometer for a precision measurement of the neutron $beta$-asymmetry with ultracold neutrons
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We describe an electron spectrometer designed for a precision measurement of the neutron $beta$-asymmetry with spin-polarized ultracold neutrons. The spectrometer consists of a 1.0-Tesla solenoidal field with two identical multiwire proportional chamber and plastic scintillator electron detector packages situated within 0.6-Tesla field-expansion regions. Select results from performance studies of the spectrometer with calibration sources are reported.
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We report the first measurement of angular correlation parameters in neutron $beta$-decay using polarized ultracold neutrons (UCN). We utilize UCN with energies below about 200 neV, which we guide and store for $sim 30$ s in a Cu decay volume. The $v
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