Test of Symmetries with Neutrons and Nuclei

TL;DR

This paper discusses precision low-energy experiments with neutrons and nuclei to explore fundamental symmetries, potential new physics beyond the standard model, and the structure of the vacuum, utilizing advanced technologies like particle trapping and exotic beams.

Contribution

It reviews recent advancements and prospects in symmetry tests using neutrons and nuclei, highlighting technological improvements and their implications for fundamental physics.

Findings

Expected increase in experimental precision by one or two orders of magnitude.

Potential to uncover new physics through decay correlation measurements.

Search for electric dipole moments indicating CP violation.

Abstract

Precision experiments at low energies probing weak interaction are a very promising and complementary tool for investigating the structure of the electro-weak sector of the standard model, and for searching for new phenomena revealing signs for an underlaying new symmetry. With the advent of new technologies in particle trapping and production of beams for exotic nuclei as well as ultracold neutrons, we expect one or two orders of magnitude gain in precision. This corresponds to the progress expected by new high luminosity B-factories or the LHC. Domains studied are $\beta$-decays where decay correlations, partial or total decay rates may reveal the nature of the left-right structure of the interaction and the investigation of discrete symmetries. Here the search for a finite electric dipole moment which, due to its CP-violating nature were sensational by itself, could shed light on the structure of the vacuum at very small distances. Last but not least ideas of a mirror world can be extended to the sector of baryons which can be studied with neutrons.