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arXiv · 1201.2214

Discrimination of $\Sigma$-nucleus potentials in the angular distribution of elastic scattering of $\Sigma^-$ hyperons from nuclei

Toru Harada·Yoshiharu Hirabayashi
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Abstract

We theoretically investigate the elastic scattering of 50-MeV $\Sigma^-$ hyperons from $^{28}$Si and $^{208}$Pb in order to clarify the radial distribution of $\Sigma$-nucleus (optical) potentials. The angular distributions of differential cross sections are calculated using several potentials that can explain experimental data of the $\Sigma^-$ atomic X-ray and ($\pi^-$, $K^+$) reaction spectra simultaneously. The magnitude and oscillation pattern of the angular distributions are understood by the use of nearside/farside decompositions of their scattering amplitudes. It is shown that the resultant angular distributions can considerably discriminate among the radial distributions of the potentials that have a repulsion inside the nuclear surface and an attraction outside the nucleus with a sizable absorption.

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Toru Harada, Yoshiharu Hirabayashi. 2012-01-11. Discrimination of $\Sigma$-nucleus potentials in the angular distribution of elastic scattering of $\Sigma^-$ hyperons from nuclei. https://doi.org/10.1103/physrevc.86.014606

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