Press Releases

DATE2021.01.08 #Press Releases

Mystery of Neutron Lifetimes, New Experiment Launched to Unravel

Disclaimer: machine translated by DeepL which may contain errors.

-A Third Approach to the Neutron Lifetime Problem

High Energy Accelerator Research Organization

J-PARC Center

Nagoya University

The University of Tokyo

Kyoto University

Kyushu University

University of Tsukuba

Osaka University


A research group led by Associate Professor Kenji Mishima, Lecturer Takashi Ino, and Research Fellow Go Ichikawa at the Institute for Materials Structure Science, High Energy Accelerator Research Organization (KEK), in collaboration with Nagoya University, The University of Tokyo, Kyoto University, Kyushu University, Osaka Electro-Communication University, University of Tsukuba, and Osaka University, developed an instrument to measure neutron lifetime with a new method different from existing methods, and obtained the first results. and obtained the first experimental results.

The decay of neutrons, one of the particles that form atomic nuclei, is closely related to the mechanism of elemental synthesis in the universe and particle physics. Based on the results of this study, it is expected that the accuracy of neutron decay lifetime measurements will be improved to further explore the mysteries of the evolution of the universe.

The results of this research were published in the journal Progress of Theoretical and Experimental Physics on January 8.

Figure: Measured neutron lifetime
Previous measurements by the bottle method and the beam method and the measurements obtained this time

For more information, please visit the websites of High Energy Accelerator Research Organization (KEK) and International Center for Elementary Particle Physics ( ICPPP ), The University of Tokyo.