Orateur
Description
The Efimov effect is a counterintuitive phenomenon concerning three non-relativistic particles with pairwise interactions supporting only one very shallow, two-particle bound state. In the so-called unitary limit, where the two-particle bound state energy goes to zero, the three-particle spectrum exhibits an infinite tower of bound states geometrically separated by a constant factor $\sim 515$. Efimov physics deals not only with the strict unitary regime, but also with the richer phenomenology slightly away from it, as long as the two-particle energies can still be considered shallow.
Observations of Efimov physics appear in cold atom experiments where the two-atom interactions can be tuned at will around the unitary regime via Feshbach resonance. In hadron physics, there are attempts at investigating some heavy exotic mesons as two- and three-body molecules and looking for universal correlations that are signatures of the Efimov effect. In this work we move away from the heavy quark sector, investigating a system with two kaons and one anti-kaon. The motivation is the shallow energies of the $a_0$ ($\sim 12$ MeV) and $f_0$ ($\sim 2$ MeV) below the two-kaon threshold. We present results for observables and evidence of universal correlations in the $K-f_0$ and $K-a_0$ scattering and the K(1460) state as candidate of an Efimov state.
