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Improved Limits on Spin-Mass Interactions
Junyi Lee1, Attaallah Almasi1, Michael Romalis1
1Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
Physical Review Letters
|May 15, 2018
Summary
Researchers searched for new forces mediated by axions or axionlike particles. This experiment improved constraints on coupling constants for very light particles, significantly advancing neutron laboratory limits.
Area of Science:
- Particle Physics
- Experimental Physics
Background:
- Axions and axionlike particles are hypothetical very light particles.
- These particles can mediate long-range forces between ordinary matter particles.
Purpose of the Study:
- To search for new forces mediated by axions or axionlike particles.
- To place improved constraints on the coupling constants of these particles.
Main Methods:
- An experiment was designed to detect forces between unpolarized nucleons in lead weights and polarized neutrons and electrons.
- A Helium-3-Potassium comagnetometer was used in conjunction with lead masses.
Main Results:
- New, improved constraints were placed on the products of scalar and pseudoscalar coupling constants.
- Constraints were set for axionlike particle masses below 10^-6 eV.
- An order of magnitude improvement over previous neutron laboratory limits was achieved.
Conclusions:
- The experiment successfully constrained the properties of axions and axionlike particles.
- This work represents a significant advancement in the search for new fundamental forces and particles.
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