AMO
In the literature: open
Axion-induced oscillating nucleon EDM at QCD-axion strength
In plain words
An axion, a proposed very light particle, would give neutrons and protons a tiny electric dipole that oscillates in time. Nuclear magnetic resonance experiments look for the resulting wobble of nuclear spins.
Precise statement
For axion dark matter with mass $m_a$ in $1e-14 \text{ to } 1e-6\,\mathrm{eV}$ and gluon coupling producing an oscillating $d_n \sim 1e-34\,e\,\mathrm{cm}$ at QCD-axion strength, determine whether an oscillating nucleon EDM or axion-nucleon gradient coupling is present at that strength, using solid-state NMR (CASPEr-type) or comagnetometers.
What would settle it
A resonant NMR or comagnetometer search reaching the QCD-axion band over at least a decade in mass.
Related problems
- Special case of Is dark matter the QCD axion? · Oscillating nucleon EDM tests QCD-axion dark matter below 1e-6 eV