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Borromean Binding of Three or Four Bosons

Steven Moszkowski·Sonia Fleck·Ali Krikeb·Lukas Theußl·Jean-Marc Richard·Kálmán Varga
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Abstract

We estimate the ratio $R=g_{3}/g_{2}$ of the critical coupling constants $g_{2}$ and $g_{3}$ which are required to achieve binding of 2 or 3 bosons, respectively, with a short-range interaction, and examine how this ratio depends on the shape of the potential. Simple monotonous potentials give $R\simeq 0.8$. A wide repulsive core pushes this ratio close to R=1. On the other hand, for an attractive well protected by an external repulsive barrier, the ratio approaches the rigorous lower bound $R=2/3$. We also present results for N=4 bosons, sketch the extension to $N>4$, and discuss various consequences.

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Steven Moszkowski, Sonia Fleck, Ali Krikeb, Lukas Theußl, Jean-Marc Richard, Kálmán Varga. 2000-03-12. Borromean Binding of Three or Four Bosons. https://doi.org/10.1103/physreva.62.032504

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