J. F. Babb, R. Higa, M. S. Hussein

The European Physical Journal A 53, 126 (2017)

15/06/2017

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 Δ -resonance ( Jπ=+3/2 , I = 3/2). We found both dynamical effects to be quite relevant for distances r between ∼50 fm up to ∼103 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.

10.1140/epja/i2017-12313-7