The Proton Radius Puzzle

Gil Paz

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arXiv · 1909.08108

The Proton Radius Puzzle

Gil Paz

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Abstract

In 2010 the proton charge radius was extracted for the first time from muonic hydrogen, a bound state of a muon and a proton. The value obtained was five standard deviations away from the regular hydrogen extraction. Taken at face value, this might be an indication of a new force in nature coupling to muons, but not to electrons. It also forces us to reexamine our understanding of the structure of the proton. Here I describe an ongoing theoretical research effort that seeks to address this "proton radius puzzle". In particular, I will present the development of new effective field theoretical tools that seek to directly connect muonic hydrogen and muon-proton scattering.

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Gil Paz. 2019-09-17. The Proton Radius Puzzle. https://arxiv.org/abs/1909.08108

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