Prediction of the analyzing power for p?+He6 elastic scattering at 200 MeV from p?+He4 elastic scattering at 200 MeV

Background: Johnson, Al-Khalili, and Tostevin constructed a theory for one-neutron halo-nucleus scattering, taking (1) the adiabatic approximation (2) neglecting interaction between valence neutron target, yielding simple relationship elastic scattering of halo nucleus its core. The core-target is calculated with reduced mass hence not measured experiment.Purpose: Our first aim to apply their $\stackrel{P\vec}{p}+^{6}\mathrm{He}$ as two-neutron improve (3) eikonal approximation. second investigate how good improved is.Methods: An valence-target-cutting (VTC) cluster-folding (CF) model.Results: VTC shows new relation two differential cross sections $\stackrel{P\vec}{p}+^{4,6}\mathrm{He}$ scattering. Using relation, we show that analyzing power ${A}_{y}(q)$ $^{6}\mathrm{He}$ same $^{4}\mathrm{He}$. In theory, ratio section $^{4}\mathrm{He}$ determines radius ${r}_{\ensuremath{\alpha}\ensuremath{-}2n}$ center neutrons; value ${r}_{\ensuremath{\alpha}\ensuremath{-}2n}=3.54$ fm. Among approximations (1)--(3), essential. order (2), CF model at 200 MeV, where potential $\stackrel{P\vec}{p}$ fitted data on $\stackrel{P\vec}{p}+^{4}\mathrm{He}$ MeV. For reproduces no free parameter. in $0.9\ensuremath{\lesssim}q\ensuremath{\lesssim}2.4\phantom{\rule{4pt}{0ex}}{\mathrm{fm}}^{\ensuremath{-}1}$, $\ensuremath{\hbar}q$ transfer momentum. predict from $^{4}\mathrm{He}$.Conclusions: