2022-06-28 オークリッジ国立研究所(ORNL)
<関連情報>
- https://www.ornl.gov/news/physicists-confront-neutron-lifetime-puzzle
- https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.128.212503
中性子寿命異常の説明としての中性子-ミラー中性子振動の実験的探索 Experimental Search for Neutron to Mirror Neutron Oscillations as an Explanation of the Neutron Lifetime Anomaly
L. J. Broussard, J. L. Barrow, L. DeBeer-Schmitt, T. Dennis, M. R. Fitzsimmons, M. J. Frost, C. E. Gilbert, F. M. Gonzalez, L. Heilbronn, E. B. Iverson, A. Johnston, Y. Kamyshkov, M. Kline, P. Lewiz, C. Matteson, J. Ternullo, L. Varriano, and S. Vavra
Physical Review Letters Published 27 May 2022
DOI:https://doi.org/10.1103/PhysRevLett.128.212503
ABSTRACT
An unexplained >4σ discrepancy persists between “beam” and “bottle” measurements of the neutron lifetime. A new model proposed that conversions of neutrons n into mirror neutrons n′, part of a dark mirror sector, can increase the apparent neutron lifetime by 1% via a small mass splitting Δm between n and n′ inside the 4.6 T magnetic field of the National Institute of Standards and Technology Beam Lifetime experiment. A search for neutron conversions in a 6.6 T magnetic field was performed at the Spallation Neutron Source which excludes this explanation for the neutron lifetime discrepancy.