Speaker
Description
I present a unified description of alpha-cluster nuclei rooted in the theory
of shallow two-body states and its connection to Efimov universality. The
starting point is the observation that the space of two-body potentials
admits a one-dimensional attractor under renormalization-group flow: all
interactions sharing the same low-energy parameters flow, in the regime
$r_e/a \lesssim 0.5$, toward the Eckart potential, whose S-matrix has
exactly two poles. One pole is the physical near-threshold state; the other
acts as an infrared cutoff fixing the resolution scale, playing a role
analogous to the three-body parameter in Efimov physics. The
$\alpha$-$\alpha$ system sits precisely inside this window, and the Coulomb repulsion converts the shallow bound state into the
narrow $^8$Be resonance — the two-body input to everything that follows.
| Theoretical or experimental | Theoretical |
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