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arXiv · 1704.01539

Density dependence of 2p-2h meson-exchange currents

J. E. Amaro·M. B. Barbaro·J. A. Caballero·A. De Pace·T. W. Donnelly·G. D. Megias·I. Ruiz Simo
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Abstract

We analyze the density dependence of the contribution of meson-exchange currents to the lepton-nucleus inclusive cross section in the two-particle two-hole channel. The model is based on the Relativistic Fermi Gas, where each nucleus is characterized by its Fermi momentum $k_F$. We find that the 2p-2h nuclear response functions at their peaks scale as $A k_F^2$ for Fermi momentum going from 200 to 300 MeV/c and momentum transfer $q$ from $2k_F$ to 2 GeV/c. This behavior is different from what is found for the quasielastic response, which scales as $A/k_F$. Additionally, the deep scaling region is also discussed and there the usual scaling behavior is found to be preferable.

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J. E. Amaro, M. B. Barbaro, J. A. Caballero, A. De Pace, T. W. Donnelly, G. D. Megias, I. Ruiz Simo. 2017-04-05. Density dependence of 2p-2h meson-exchange currents. https://doi.org/10.1103/physrevc.95.065502

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