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Do final state interactions obscure short range correlation effects in quasielastic $A(e,e'p)$ scattering?

A. Bianconi·S. Jeschonnek·N. N. Nikolaev·B. G. Zakharov
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Abstract

Are short range correlations in the ground state of the target nucleus (initial state correlations ISC)observable inexperiments on quasielastic $A(e,e'p)$ scattering at large missing momentum $p_{m}$? Will the missing momentum spectrum observed at CEBAF be overwhelmed by final state interactions of the struck proton? Taking the $^{4}He$ nucleus with a realistic model wave function for a testing ground, we present a full calculation of the missing momentum distribution in inclusive $^{4}He(e,e'p)$ scattering. We find a complex interplay and strong quantum-mechanical interference of FSI and ISC contributions to scattering at large $p_{m}$, with drastic change of the interference pattern from the (anti)parallel to transverse kinematics. We show that in all the kinematical conditions, for missing momenta $p_{m}\gsim 1$\,fm$^{-1}$, quasielastic scattering is dominated by FSI effects and the sensitivity to details of the nuclear ground state is lost. The origin of the FSI dominance is well understood and can be traced back to the anisotropic behaviour of FSI which is long ranged in the longitudinal direction and short ranged in the transverse direction in the opposite to the short ranged ground state correlations.

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A. Bianconi, S. Jeschonnek, N. N. Nikolaev, B. G. Zakharov. 1995-08-17. Do final state interactions obscure short range correlation effects in quasielastic $A(e,e'p)$ scattering?. https://doi.org/10.1016/0375-9474(96)00248-5

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