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The $\gamma^\ast N \to N(1520)$ transition has a property that differs fromthe other low lying nucleon resonance amplitudes: the magnitude of thetransverse helicity amplitudes. The transition helicity amplitudes are definedin terms of square transfer momentum $q^2$, or $Q^2=-q^2$. Near the photonpoint ($Q^2=0$) there is a significant difference in the magnitude of thetransverse amplitudes: $A_{3/2}$ is very large and $A_{1/2}$ is very small.This atypical behavior contrasts with the relation between the amplitudes atthe pseudothreshold (the limit where the nucleon and the $N(1520)$ are both atrest and $Q^2 <0$), where $A_{3/2} = A_{1/2}/\sqrt{3}$, and also in the large$Q^2$ region, where theory and data suggest that $A_{3/2}$ is suppressedrelative to $A_{1/2}$. In the present work, we look for the source of thesuppression of the $A_{1/2}$ amplitude at $Q^2=0$. The result is easy tounderstand in first approximation, when we look into the relation between thetransverse amplitudes and the elementary form factors, defined by a gaugeinvariant parametrization of the $\gamma^\ast N \to N(1520)$ transitioncurrent, near $Q^2=0$. There is a partial cancellation between contributions oftwo {\it elementary} form factors near $Q^2=0$. We conclude, however, that thecorrelation between the these elementary form factors at $Q^2=0$ is notsufficient to explain the transverse amplitude data below $Q^2 = 1$ GeV$^2$.The description the dependence of the transverse amplitudes on $Q^2$ requiresthe determination of the scale of variation of the elementary form factors inthe range $Q^2=0$...0.5 GeV$^2$, a region with almost non existent data. Weconclude at the end that the low $Q^2$ data for the transverse amplitudes canbe well described when we relate the scale of variation of the elementary formfactors with the nucleon dipole form factor.

About the magnitude of the $\gamma^\ast N \to N(1520)$ transverse amplitudes near $Q^2=0$