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Effect of nucleon structure variation on the longitudinal response function

K. Saito·K. Tsushima·A. W. Thomas
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Abstract

Using the quark-meson coupling (QMC) model, we study the longitudinal response function for quasielastic electron scattering from nuclear matter. In QMC the coupling constant between the scalar ($σ$) meson and the nucleon is expected to decrease with increasing nuclear density, because of the self-consistent modification of the structure of the nucleon. The reduction of the coupling constant then leads to a smaller contribution from relativistic RPA than in the Walecka model. However, since the electromagnetic form factors of the in-medium nucleon are modified at the same time, the longitudinal response function and the Coulomb sum are reduced by a total of about 20% in comparison with the Hartree contribution. We find that the relativistic RPA and the nucleon structure variation both contribute about fifty-fifty to the reduction of the longitudinal response.

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K. Saito, K. Tsushima, A. W. Thomas. 1999-04-21. Effect of nucleon structure variation on the longitudinal response function. https://doi.org/10.1016/s0370-2693(99)01087-4

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