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arXiv · nucl-th/9511011

Correlated $ππ$ and $K\bar K$ exchange in the baryon-baryon interaction

A. Reuber·K. Holinde·H. -C. Kim·J. Speth
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Abstract

A dynamical model for correlated two-pion and two-kaon exchange in the baryon- baryon interaction is presented, both in the scalar-isoscalar ($σ$) and the vector-isovector ($ρ$) channel. The correlations between the two pseudoscalar mesons are taken into account by means of $ππ- K\bar K$ amplitudes derived from a meson-exchange model, which is in line with the empirical $ππ$ data. It is found that correlated $K\bar K$ exchange plays an important role in the $σ$-channel for baryon-baryon states with non- vanishing strangeness. The strength of correlated $ππ$ plus $K\bar K$ exchange in the $σ$-channel decreases with the strangeness of the baryon- baryon system becoming more negative. The results for correlated $ππ$- exchange in the vector-isovector channel deviate from what is expected in the naive SU(3) picture for genuine $ρ$-exchange. Shortcomings of a simplified description in terms of sharp mass $σ$- and $ρ$-exchange are pointed out.

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A. Reuber, K. Holinde, H. -C. Kim, J. Speth. 1995-11-10. Correlated $ππ$ and $K\bar K$ exchange in the baryon-baryon interaction. https://doi.org/10.1016/0375-9474(96)00256-4

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