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arXiv · 1610.09760

Proton radius from electron-proton scattering and chiral perturbation theory

Marko Horbatsch·Eric A. Hessels·Antonio Pineda
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Abstract

We determine the root-mean-square proton charge radius, $R_{\rm p}$, from a fit to low-$Q^2$ electron-proton elastic scattering cross section data with the higher moments fixed (within uncertainties) to the values predicted by chiral perturbation theory. We obtain $R_{\rm p}=0.857(11)$ fm. This number falls between the value obtained from muonic hydrogen analyses and the CODATA value (based upon atomic hydrogen spectroscopy and electron-proton scattering determinations).

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Marko Horbatsch, Eric A. Hessels, Antonio Pineda. 2017-03-28. Proton radius from electron-proton scattering and chiral perturbation theory. https://doi.org/10.1103/physrevc.95.035203

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