We derive relation formulas for proton depolarizations in proton-${}^3\mathrm{He}$ ($p\text{−}$${}^3\mathrm{He}$) elastic scattering in a form that makes it easy to identify contributions of spin-dependent interactions. The formulas explain approximate relations found in the depolarizations measured at $E_p=800\text{MeV}$ when the magnitudes of scattering amplitudes due to $p\text{−}$${}^3\mathrm{He}$ spin–spin and tensor interactions are small. This nature of the interactions is investigated from the viewpoint of folding models. It is shown that the spin–spin and tensor interactions are significantly diminished owing to characteristics of nucleon densities of ${}^3\mathrm{He}$, which are calculated from a solution of the Faddeev equation. A folding model calculation with the densities and a simple nuclear potential shows that the $p\text{−}$${}^3\mathrm{He}$ spin–spin interaction is much weaker than the spin-independent central interaction.

• Received 3 February 2005
• Publisher error corrected 31 August 2005

DOI:https://doi.org/10.1103/PhysRevC.72.027601