A study of beta-delayed deuteron emission from helium-6

The decay of {dollar}sp6{dollar}He has been well studied for its strong ground-state to ground-state, Gamow-Teller beta transition. Recently, the nuclide has been the subject of intense study as it exhibits new, unique decay properties reflecting an exotic nuclear structure. Studies have shown that {dollar}sp6{dollar}He decays weakly by beta-delayed deuteron emission while other, independent measurements have revealed a halo-like distribution of the {dollar}sp6{dollar}He neutron matter.; It has been postulated that observable quantities such as the {dollar}sp6{dollar}He break-up probability and the energy spectrum of the emitted deuterons are sensitive probes of the so-called 'Neutron Halo' phenomenon. However, the two previous determinations of the branching ratio for deuteron emission are not self-consistent and the published particle energy spectra lack the statistical accuracy necessary for conclusive theoretical interpretation.; A recent study conducted at the TRIUMF facility employed a coincidence technique to re-measure the deuteron emission probability and to generate the energy spectra of the emitted particles. The branching ratio for the emission of deuterons above the 350 keV laboratory threshold has been measured to be (1.9 {dollar}pm{dollar} 0.2 {dollar}pm{dollar} 0.7 {dollar}*{dollar} 10{dollar}sp{lcub}-6{rcub}{dollar}) while the deuteron energy spectrum collected with this technique shows a statistical improvement of better than an order of magnitude over those previously reported.; Within this study, K- and R-Matrix nuclear reaction theories have been utilized to estimate the total integrated break-up probability and to understand the observed decay in terms of the anomalous halo structure.