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arXiv · 1112.4265

Effects of consistent and inconsistent isobar coupling in the nuclear medium

C. L. Korpa
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Abstract

We investigate effects of consistent (conserving the number of degrees of freedom) and inconsistent pion-nucleon-isobar couplings on the isobar propagator in vacuum and in nuclear medium. Using the consistent coupling in conjunction with a convenient basis leads to significant simplification of the isobar vacuum and in-medium self energy and dressed propagator compared to the case of inconsistent interaction. The higher-derivative nature of the consistent interaction requires a suitable compensation by an additional form-factor term or adjustment in the used cut-off values. This modification is straightforward to perform and assures that the physical observables connected to the spin-3/2 sector in vacuum and nuclear medium acquire values indistinguishable from the ones obtained by using an inconsistent coupling.

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C. L. Korpa. 2011-12-19. Effects of consistent and inconsistent isobar coupling in the nuclear medium. https://doi.org/10.1103/physrevc.85.014601

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