New Limits on Exotic Spin-Dependent Interactions at Astronomical Distances

Area of Science:

• Modern physics
• Particle physics
• Astrophysics

Background:

• Exotic spin-dependent interactions involving new light particles are crucial for addressing fundamental questions in physics.
• These interactions can manifest in various forms between polarized neutrons and unpolarized nucleons.
• Potential astrophysical sources like the Sun and Moon could induce detectable variations in laboratory settings.

Purpose of the Study:

• To derive new experimental upper limits on exotic spin-dependent interactions at astronomical ranges.
• To improve constraints on specific interaction types, including scalar-pseudoscalar, vector-axial-vector, and axial-axial-vector.
• To extend the analysis to Hari Dass interactions and establish new constraints.

Main Methods:

• Analysis of existing data from laboratory measurements on Lorentz and CPT violation.
• Utilizing astronomical observations to probe spin-dependent interactions.
• Applying theoretical frameworks to derive experimental upper limits.

Main Results:

• Established the most stringent experimental upper limits to date on g_{S}^{N}g_{P}^{n} interactions, surpassing previous combined astrophysical-laboratory limits.
• Reported new constraints on vector-axial-vector and axial-axial-vector interactions at astronomical scales, with vector-axial-vector limits improved significantly.
• Derived new constraints on Hari Dass interactions.

Conclusions:

• The study provides the tightest experimental constraints on exotic spin-dependent interactions to date.
• The findings contribute to the search for new physics beyond the Standard Model.
• This research advances our understanding of fundamental interactions and their astrophysical implications.