Searches for Exotic Interactions Using Neutrons

Abstract

Slow neutrons possess several advantageous properties which make them useful probes for a variety of exotic interactions, including some that can form at least some components of the dark matter of interest for this issue of Symmetry. We discuss the relevant neutron properties, describe some of the recent work that has been done along these lines using neutron experiments mainly with cold and ultra-cold neutrons, and outline some interesting and exciting opportunities which can be pursued using resonant epithermal neutron interactions in heavy nuclei.

Spin-Textured Neutron Beams with Orbital Angular Momentum

“…While neutron beams are successfully utilized as indirect probes of many exotic phases of matter, such as quantum spin liquids and magnetic skyrmion lattices [32,33], or as test particles to investigate fundamental physical phenomena including gravity and dark matter [34], a creative endeavor lies in producing arbitrary neutron states. In this work, we have presented an experimental protocol to generate neutron beams with spin textures that couple to the neutron's orbital motion and impart OAM to the beam.…”

Powders of Diamond Nanoparticles as a Promising Material for Reflectors of Very Cold and Cold Neutrons

“…The design of reflectors of such neutrons based on NDs can significantly increase VCN/CN fluxes and expand the scope of such neutrons for solving applied and fundamental problems. In particular, some of these topics were recently mentioned when discussing particle physics at the European Spallation Source in Lund, Sweden [ 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ].…”

Neutron-neutral particle mixing and its observable consequences

“…Cold neutrons serve as a rich and varied environment where many interesting processes occur [13], making it possible to search for new physical phenomena in a smaller experiment, comparing with the ones at the LHC. The neutron lifetime and the neutron-antineutron (n-n) oscillation time are the two key observables that are investigated intensively [14][15][16][17][18][19][20][21][22][23].…”