PoS - Proceedings of Science
Volume 380 - Particles and Nuclei International Conference 2021 (PANIC2021) - Tests of symmetries and conservation laws
Improvement of systematic uncertainties for the neutron lifetime experiment at J-PARC
T. Mogi*, T. Hasegawa, K. Hirota, G. Ichikawa, S. Ieki, T. Ino, Y. Iwashita, S. Kajiwara, Y. Kato, M. Kitaguchi, R. Kitahara, J. Koga, S. Makise, S. Matsuzaki, K. Mishima, K. Morikawa, N. Nagakura, H. Okabe, H. Otono, Y. Seki, D. Sekiba, T. Shima, H. Shimizu, H.M. Shimizu, Y. Sugisawa, N. Sumi, H. Sumino, T. Tanabe, T. Tomita, H. Uehara, T. Yamada, S. Yamashita, K. Yano and T. Yoshiokaet al. (click to show)
Full text: pdf
Pre-published on: March 02, 2022
Published on: May 24, 2022
Abstract
The neutron lifetime is one of the important parameters for particle physics and astrophysics. There is a 4.6$\sigma$ (9.5 s) discrepancy between the results of the two typical methods. To solve this discrepancy, a new neutron lifetime experiment with a different method is in progress at J-PARC, and this experiment published the first result in 2020 of $898 \pm 10 (\mathrm{stat.}) +15/-18 (\mathrm{syst.})\,\mathrm{s}$. We have performed improvements to reduce systematic uncertainties towards 1 s accuracy. The methods to measure the amount of $\mathrm{^3He}$ injected and in the working gas have been upgraded, and a new model for the space charge effect in the Monte Carlo simulation has been implemented.
DOI: https://doi.org/10.22323/1.380.0458
How to cite

Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.

Open Access
Creative Commons LicenseCopyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.