Many-channel microscopic theory of resonance states and scattering processes in Be9 and B9

We present a many-channel microscopic model that extends the three-cluster model previously formulated by Vasilevsky et al. [Nucl. Phys. A 824, 37 (2009)]. This extended model incorporates multiple three-cluster configurations, which are subsequently reduced to a comprehensive set of binary channels. These channels dictate the dynamics of various nuclear processes and the resonance structure of a compound nucleus across a broad energy spectrum. The application of this model focuses on investigating the nature of high-energy resonance states in ⁹Be and ⁹B, as well as the astrophysical S factors for the reactions ⁷Li(d,n)αα and ⁷Be(d,p)αα, particularly pertinent to the cosmological lithium problem. Parametrization of resonance states is performed across a wide range of total angular momenta and includes states of both positive and negative parity. Dominant decay channels are identified for each resonance state. Detailed analysis of astrophysical S factors resulting from deuteron interactions with ⁷Li and ⁷Be is conducted within an energy range from zero to 2 MeV. Four exit channels in ⁹Be [⁸Be(0⁺)+n, ⁸Be(2⁺)+n, ⁵He(3/2^-)+α, ⁵He(1/2^-)+α] and four in ⁹B [⁸Be(0⁺)+p, ⁸Be(2⁺)+p, ⁵Li(3/2^-)+α, ⁵Li(1/2^-)+α] are considered. A clear hierarchy of reactions is established for the energy range 0≤E<1.0 MeV. Notably, reactions ⁷Li+d=⁸Be(0⁺)+n and ⁷Be+d=⁸Be(0⁺)+p substantially dominate over all other reactions within this energy range. The model satisfactorily describes the experimental astrophysical S factors for these reactions.