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arXiv · 0704.1461

Trajectory of neutron$-$neutron$-^{18}C$ excited three-body state

M. T. Yamashita·T. Frederico·Lauro Tomio
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Abstract

The trajectory of the first excited Efimov state is investigated by using a renormalized zero-range three-body model for a system with two bound and one virtual two-body subsystems. The approach is applied to $n-n-^{18}$C, where the $n-n$ virtual energy and the three-body ground state are kept fixed. It is shown that such three-body excited state goes from a bound to a virtual state when the $n-^{18}$C binding energy is increased. Results obtained for the $n-^{19}$C elastic cross-section at low energies also show dominance of an $S-$matrix pole corresponding to a bound or virtual Efimov state. It is also presented a brief discussion of these findings in the context of ultracold atom physics with tunable scattering lengths.

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M. T. Yamashita, T. Frederico, Lauro Tomio. 2007-04-11. Trajectory of neutron$-$neutron$-^{18}C$ excited three-body state. https://doi.org/10.1016/j.physletb.2008.01.008

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