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arXiv · 1405.7133

Testing in-medium $πN$ dynamics on pionic atoms

E. Friedman·A. Gal
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Abstract

A general algorithm for handling the energy dependence of meson-nucleon amplitudes in the nuclear medium has been recently applied to antikaons and to eta mesons. Here we test this approach on $πN$ amplitudes in pionic atoms where direct comparison can be made with ample experimental results. Applying this algorithm to a large-scale fit of 100 pionic-atom data points across the periodic table, which also include the `deeply-bound' states in Sn and Pb, reaffirms earlier conclusions on the density-dependent renormalization of the $πN$ threshold isovector amplitude $b_1$, or equivalently the renormalization of the pion decay constant $f_π$ in the nuclear medium.

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E. Friedman, A. Gal. 2014-06-16. Testing in-medium $πN$ dynamics on pionic atoms. https://doi.org/10.1016/j.nuclphysa.2014.05.017

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