Precise neutron lifetime experiment using pulsed neutron beams at J-PARC

Naoki Nagakura; Katsuya Hirota; Sei Ieki; Takashi Ino; Yoshihisa Iwashita; Masaaki Kitaguchi; Ryunosuke Kitahara; Kenji Mishima; Aya Morishita; Hideyuki Oide; Hidetoshi Otono; Risa Sakakibara; Yoshichika Seki; Tatsushi Shima; Hirohiko M. Shimizu; Tomoaki Sugino; Naoyuki Sumi; Hiroshima Sumino; Kaoru Taketani; Genki Tanaka; Tatsuhiko Tomita; Takahito Yamada; Satoru Yamashita; Mami Yokohashi; Tamaki Yoshioka

arXiv · 1702.03099

Precise neutron lifetime experiment using pulsed neutron beams at J-PARC

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Abstract

The neutron lifetime is one of the basic parameters in the weak interaction, and is used for predicting the light element abundance in the early universe. Our group developed a new setup to measure the lifetime with the goal precision of 0.1% at the polarized beam branch BL05 of MLF, J-PARC. The commissioning data was acquired in 2014 and 2015, and the first set of data to evaluate the lifetime in 2016, which is expected to yield a statistical uncertainty of O(1)%. This paper presents the current analysis results and the future plans to achieve our goal precision.

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Naoki Nagakura, Katsuya Hirota, Sei Ieki, Takashi Ino, Yoshihisa Iwashita, Masaaki Kitaguchi, Ryunosuke Kitahara, Kenji Mishima, Aya Morishita, Hideyuki Oide, Hidetoshi Otono, Risa Sakakibara, Yoshichika Seki, Tatsushi Shima, Hirohiko M. Shimizu, Tomoaki Sugino, Naoyuki Sumi, Hiroshima Sumino, Kaoru Taketani, Genki Tanaka, Tatsuhiko Tomita, Takahito Yamada, Satoru Yamashita, Mami Yokohashi, Tamaki Yoshioka. 2017-02-10. Precise neutron lifetime experiment using pulsed neutron beams at J-PARC. https://arxiv.org/abs/1702.03099

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