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arXiv · 0906.5020

Neutron Charge Density from Simple Pion Cloud Models

Jared A. Rinehimer·Gerald A. Miller
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Abstract

The physical nucleon is modeled as a bare nucleon surrounded by a pion cloud using a psuedoscalar pion-nucleon coupling to examine its implications for the neutron form factor, F_1, and the corresponding transverse charge density in the infinite momentum frame. Two versions, one with a tunable Pauli-Villars parameter, and one with light-front cloudy-bag pion-nucleon form factors, are examined. A qualitative agreement with the experimental form factor (negative definite for all Q^2) and transverse charge density are achieved when the nucleon is treated as having a finite extent. The bare nucleon must have a finite extent if this model is to account for a negative definite F_1, and consequently a negative transverse charge density of the neutron at its center.

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BibTeXRIS

Jared A. Rinehimer, Gerald A. Miller. 2009-06-26. Neutron Charge Density from Simple Pion Cloud Models. https://doi.org/10.1103/physrevc.80.025206

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