The A_y-Problem in Refined Resonating Group Model calculations for (p-³{rm He}) Scattering

We report on a microscopic Refined Resonating Group Model (RRGM) calculation of scattering of $p$ off ${}^3{\rm He}$ employing the Argonne-$v_{14}$ and the Bonn nucleon-nucleon potentials without three-nucleon forces at low energies up to 30 MeV. The calculated phase-shifts verify the well-known proton analyzing power $A_y$-problem. We demonstrate that with corrected ${}^3P_2$ phase-shifts experimental differential cross-section and analyzing power data can be explained.