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arXiv · 1504.05131

Three-pion exchange nucleon-nucleon potentials with virtual $Δ$-isobar excitation

N. Kaiser
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Abstract

The nucleon-nucleon interaction arising from the exchange of three pions and the excitation of $Δ(1232)$-isobars in intermediate states is studied. Approximating the $Δ$-propagator by the inverse $Δ$N mass-splitting, analytical expressions are derived for the spectral-functions of the isoscalar and isovector central, spin-spin and tensor NN-potentials in momentum-space. A trans- lation of the spectral-functions into coordinate-space potentials reveals that the main effect of these specific exchange and excitation mechanisms is a repulsive isoscalar central NN-potential.

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N. Kaiser. 2015-04-20. Three-pion exchange nucleon-nucleon potentials with virtual $Δ$-isobar excitation. https://doi.org/10.1103/physrevc.92.024002

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