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Effective Masses and Sizes of N(939), $Δ\!\!\mbox{\boldmath(1232)}$ and N(1440) in Nuclear Medium

Hiroko Ichie·Arata Hatashigaki·Akira Suzuki·Masahiro Kimura
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Abstract

The effective masses and sizes of N(939), $Δ(1232)$ and N(1440) in nuclear medium are calculated for a model in which quarks are subjected to a confinement force quenched by the scalar part of nuclear interactions. At the nuclear matter density, the nucleon swells by 50\% relative to the free nucleon. The masses of $Δ(1232)$ and N(1440) decrease in nuclear medium more than the nucleon, so that the pion requires less energy to excite them in nuclear medium than it does for a free nucleon.

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Hiroko Ichie, Arata Hatashigaki, Akira Suzuki, Masahiro Kimura. 1993-08-20. Effective Masses and Sizes of N(939), $Δ\!\!\mbox{\boldmath(1232)}$ and N(1440) in Nuclear Medium. https://arxiv.org/abs/nucl-th/9308017

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