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Moments of the neutron charge form factor and the N->Delta quadrupole transition

P. Grabmayr·A. J. Buchmann
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Abstract

Recent data allow a new parametrization of the neutron charge form factor G_En. A parameter-free quark model relation between G_En and the N->Delta quadrupole form factor is used to predict the latter from the G_En data. In particular, the neutron charge radius is related to N->Delta quadrupole moment, while the fourth moment of G_En connects to the N->Delta quadrupole transition radius. From the latter we derive an experimental value for the charge radius of the light constituent quarks. Finally, the C2/M1 ratio in pion electroproduction is predicted from the elastic neutron form factor data.

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P. Grabmayr, A. J. Buchmann. 2001-04-20. Moments of the neutron charge form factor and the N->Delta quadrupole transition. https://doi.org/10.1103/physrevlett.86.2237

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