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arXiv · 1112.2823

Energy dependence of $K^-$-"$pp$" effective potential derived from coupled-channel Green's function

Takahisa Koike·Toru Harada
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Abstract

We investigate the energy dependence of a single-channel effective potential between the $K^-$ and the "$pp$"-core nucleus, which can be obtained as an $K^-$-"$pp$" equivalent local potential from a coupled-channel model for $\bar{K}(NN)$-$π(ΣN)$ systems. It turns out that the imaginary part of the resultant potential near the $πΣN$ decay threshold can well approximate the phase space suppression factor of $K^-pp \to πΣN$ decay modes. The effects on the pole position of the $π(ΣN)$ state in the $πΣN$ channel are also discussed.

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Takahisa Koike, Toru Harada. 2011-12-13. Energy dependence of $K^-$-"$pp$" effective potential derived from coupled-channel Green's function. https://doi.org/10.1007/s10751-011-0531-1

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