Dipole-dipole dispersion interactions between neutrons

Abstract

We investigate the long-range interactions between two neutrons utilizing recent data on the neutron static and dynamic electric and magnetic dipole polarizabilities. The resulting long-range potentials are used to make quantitative comparisons between the collisions of a neutron with a neutron and a neutron with a proton. We also assess the importance of the first pion production threshold and first excited state of the nucleon, the $\Delta$-resonance ($J^{\pi }$ = + 3/2, I = 3/2). We found both dynamical effects to be quite relevant for distances r between ~ 50 fm up to ~$10^3$ fm in the nn system, the neutron-wall system and in the wall-neutron-wall system, reaching the expected asymptotic limit beyond that. Relevance of our findings to the confinement of ultra cold neutrons inside bottles is discussed.

11 pages, 12 figures, Version to be published in the European Physical Journal A (2017)

References in corpus (7)

• Using effective field theory to analyse low-energy Compton scattering data from protons and light nuclei
• Charge Symmetry Breaking and QCD
• Nucleon Polarizabilities: from Compton Scattering to Hydrogen Atom
• Predictions of covariant chiral perturbation theory for nucleon polarisabilities and polarised Compton scattering
• Quantum Gravitational Force Between Polarizable Objects
• Casimir effects in atomic, molecular, and optical physics
• What different variants of chiral EFT predict for the proton Compton differential cross section - and why

Cited by in corpus (2)

• Dipole-dipole interactions between neutrons
• Few-neutron systems with the long-range Casimir-Polder force