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arXiv · 1212.1562

Inelastic cross sections and continuum transitions illustrated by $^{8}$Be results

E. Garrido·A. S. Jensen·D. V. Fedorov
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Abstract

We use the two-alpha cluster model to describe the properties of $^{8}$Be. The $E2$-transitions in a two-body continuum can be described as bremsstrahlung in an inelastic scattering process. We compute cross sections as functions of initial energy for the possible $E2$-transitions from initial angular momenta $(0^+,2^+,4^+,6^+,8^+)$. The dependence on the exact shape of potentials is very small when the low-energy scattering phase-shifts are the same. We relate to practical observables where energies of the emerging alpha-particles are restricted in various ways. The unphysical infrared contribution is removed. We find pronounced peaking for photon energies matching resonance positions. Contributions from intra-band transitions are rather small although substantial (and even dominating) for initial energies between resonances. Structure information are derived but both ${\cal B}^{(E2)}$ values and electromagnetic transition rates are ambiguous in the continuum.

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E. Garrido, A. S. Jensen, D. V. Fedorov. 2012-12-07. Inelastic cross sections and continuum transitions illustrated by $^{8}$Be results. https://doi.org/10.1103/physrevc.86.064608

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