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arXiv · 2601.20762

A Zero-Range Model for the Efimov Effect in the Born-Oppenheimer Approximation

G. Basti·D. Ferretti·A. Teta
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Abstract

In this note we discuss the Efimov effect emerging in a three-particle quantum system with zero-range interactions. In particular, we consider two non-interacting identical bosons plus a different lighter particle such that the interaction between a boson and the light particle is resonant. We also assume the validity of the Born-Oppenheimer approximation. Under these conditions, we show that the three-particle system exhibits infinitely many negative eigenvalues which accumulate at zero and satisfy the universal geometrical law characterising the Efimov effect. The result we find is a generalisation of previous results recently obtained in [13, 24].

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G. Basti, D. Ferretti, A. Teta. 2026-01-28. A Zero-Range Model for the Efimov Effect in the Born-Oppenheimer Approximation. https://arxiv.org/abs/2601.20762

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