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arXiv · nucl-th/9705016

Sub-threshold resonances in few-neutron systems

S. A. Sofianos·S. A. Rakityansky·G. P. Vermaak
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Abstract

Three- and four-neutron systems are studied within the framework of the hyperspherical approach with a local S-wave nn-potential. Possible bound and resonant states of these systems are sought as zeros of three- and four-body Jost functions in the complex momentum plane. It is found that zeros closest to the origin correspond to sub-threshold (nnn) (1/2-) and (nnnn) (0+) resonant states. The positions of these zeros turned out to be sensitive to the choice of the $nn$--potential. For the Malfliet- Tjon potential they are E(nnn)=-4.9-i6.9 (MeV) and E(nnnn)=-2.6-i9.0 (MeV). Movement of the zeros with an artificial increase of the potential strength also shows an extreme sensitivity to the choice of potential. Thus, to generate ^3n and ^4n bound states, the Yukawa potential needs to be multiplied by 2.67 and 2.32 respectively, while for the Malfliet-Tjon potential the required multiplicative factors are 4.04 and 3.59.

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S. A. Sofianos, S. A. Rakityansky, G. P. Vermaak. 1997-05-08. Sub-threshold resonances in few-neutron systems. https://doi.org/10.1088/0954-3899%2F23%2F11%2F010

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