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arXiv · 1703.02323

A new measurement of electron transverse polarization in polarized nuclear beta decay

H. Kawamura·T. Akiyama·M. Hata·Y. Hirayama·M. Ikeda·Y. Ikeda·T. Ishii·D. Kameda·S. Mitsuoka·H. Miyatake·D. Nagae·Y. Nakaya·K. Ninomiya·M. Nitta·N. Ogawa·J. Onishi·E. Seitaibashi·S. Tanaka·R. Tanuma·Y. Totsuka·T. Toyoda·Y. X. Watanabe·J. Murata
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Abstract

The Mott polarimetry for T -Violation (MTV) experiment tests time-reversal symmetry in polarized nuclear beta decay by measuring an electron's transverse polarization as a form of angular asymmetry in Mott scattering using a thin metal foil. A Mott scattering analyzer system developed using a tracking detector to measure scattering angles offers better event selectivity than conventional counter experiments. In this paper, we describe a pilot experiment conducted at KEK-TRIAC using a prototype system with a polarized 8Li beam. The experiment confirmed the sound performance of our Mott analyzer system to measure T-violating triple correlation (R correlation), and therefore recommends its use in higher-precision experiments at the TRIUMF-ISAC.

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H. Kawamura, T. Akiyama, M. Hata, Y. Hirayama, M. Ikeda, Y. Ikeda, T. Ishii, D. Kameda, S. Mitsuoka, H. Miyatake, D. Nagae, Y. Nakaya, K. Ninomiya, M. Nitta, N. Ogawa, J. Onishi, E. Seitaibashi, S. Tanaka, R. Tanuma, Y. Totsuka, T. Toyoda, Y. X. Watanabe, J. Murata. 2017-03-07. A new measurement of electron transverse polarization in polarized nuclear beta decay. https://doi.org/10.1142/s0217732317500584

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