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arXiv · 0906.5598

Meson-exchange currents and final-state interactions in quasielastic electron scattering at high momentum transfers

J. E. Amaro·M. B. Barbaro·J. A. Caballero·T. W. Donnelly·C. Maieron·J. M. Udias
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Abstract

The effects of meson-exchange currents (MEC) are computed for the one-particle one-hole transverse response function for finite nuclei at high momentum transfers $q$ in the region of the quasielastic peak. A semi-relativistic shell model is used for the one-particle-emission $(e,e')$ reaction. Relativistic effects are included using relativistic kinematics, performing a semi-relativistic expansion of the current operators and using the Dirac-equation-based (DEB) form of the relativistic mean field potential for the final states. It is found that final-state interactions (FSI) produce an important enhancement of the MEC in the high-energy tail of the response function for $q\geq 1$ GeV/c. The combined effect of MEC and FSI goes away when other models of the FSI, not based on the DEB potential, are employed.

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J. E. Amaro, M. B. Barbaro, J. A. Caballero, T. W. Donnelly, C. Maieron, J. M. Udias. 2009-06-30. Meson-exchange currents and final-state interactions in quasielastic electron scattering at high momentum transfers. https://doi.org/10.1103/physrevc.81.014606

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