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arXiv · 1010.3629

Realistic Transverse Images of the Proton Charge and Magnetic Densities

Siddharth Venkat·John Arrington·Gerald A. Miller·Xiaohui Zhan
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Abstract

We develop a technique, denoted as the finite radius approximation (FRA), that uses a two-dimensional version of the Shannon-Nyquist sampling theorem to determine transverse densities and their uncertainties from experimental quantities. Uncertainties arising from experimental uncertainties on the form factors and lack of measured data at high $Q^2$ are treated. A key feature of the FRA is that a form factor measured at a given value of $Q^2$ is related to a definite region in coordinate space. An exact relation between the FRA and the use of a Bessel series is derived. The proton Dirac form factor is well enough known such that the transverse charge density is very accurately known except for transverse separations $b$ less than about 0.1 fm. The Pauli form factor is well known to $Q^2$ of about 10 GeV$^2$, and this allows a reasonable, but improvable, determination of the anomalous magnetic moment density.

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Siddharth Venkat, John Arrington, Gerald A. Miller, Xiaohui Zhan. 2010-10-18. Realistic Transverse Images of the Proton Charge and Magnetic Densities. https://doi.org/10.1103/physrevc.83.015203

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