Evidence of a near-threshold resonance in \(^{11}\)B relevant to the \(\beta\)-delayed proton emission of \(^{11}\)Be

A narrow near-threshold proton-emitting resonance (Ex = 11.4 MeV, J\(^{\pi}\) = 1/2\(^{+}\) and \(\Gamma_{p}\) = 4.4 keV) was directly observed in \(^{11}\)B via proton resonance scattering. This resonance was previously inferred in the \(\beta\)-delayed proton emission of the neutron halo nucleus \(^{11}\)Be. The good agreement between both experimental results serves as a ground to confirm the existence of such exotic decay and the particular behavior of weakly bound nuclei coupled to the continuum. \(R\)-matrix analysis shows a sizable partial decay width for both, proton and \(\alpha\) emission channels.