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arXiv · 1907.00110

Confinement in Nuclei and the Expanding Proton

Gerald A. Miller
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Abstract

High-precision knowledge of electromagnetic form factors of nuclei is a subject of much current experimental and theoretical activity in nuclear and atomic physics. Such precision mandates that effects of the non-zero spatial extent of the constituent nucleons be handled in a manner that goes beyond the usual impulse approximation. A series of simple, Poincare-invariant, composite-proton models that respect the Ward-Takahashi identity and in which quarks are confined are used to study the validity of this approximation. The result of all of the models is a general theorem showing that medium modification of proton structure must occur. Combining this result with lattice QCD calculations leads to a conclusion that a bound proton must be larger than a free one.

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Gerald A. Miller. 2019-07-11. Confinement in Nuclei and the Expanding Proton. https://doi.org/10.1103/physrevlett.123.232003

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