Limits on a CP-violating scalar axion-nucleon interaction
Abstract
Axions or similar hypothetical pseudoscalar bosons may have a small CP-violating scalar Yukawa interaction gs(N) with nucleons, causing macroscopic monopole-dipole forces. Torsion-balance experiments constrain gp(e) gs(N), whereas gp(N) gs(N) is constrained by the depolarization rate of ultra-cold neutrons or spin-polarized nuclei. However, the pseudoscalar couplings gp(e) and gp(N) are strongly constrained by stellar energy-loss arguments and gs(N) by searches for anomalous monopole-monopole forces, together providing the most restrictive limits on gp(e) gs(N) and gp(N) gs(N). The laboratory limits on gs(N) are currently the most restrictive constraints on CP-violating axion interactions.
Turn this paper into a lesson
ArcXiv compiles a structured reading guide from this paper's metadata: plain-English importance, contributions, prerequisite concepts, which sections to read first, flashcards, and a quiz. Grounded in the abstract, never invented.