Proton Electromagnetic Form Factors in the Time-like Region through the Scan Technique

Abstract

For over 100 years, scientists have investigated the properties of the proton, which is one of the most abundant components of visible matter in the universe. Nevertheless, researchers do not fully understand many details about its internal structure and dynamics. Time-like electromagnetic form factors are one of the observable quantities that can help us achieve a deeper understanding. In this review article, we present an overview of the current experimental status in this field, consisting of measurements of the time-like reactions $e^{+}{e}^{-}\to p\bar{p}$, $p\bar{p}\to e^{+}{e}^{-}$, and future measurements of $p\bar{p}\to {\mu }^{+}{\mu }^{-}$. A focus is put on recent high precision results of the reaction $e^{+}{e}^{-}\to p\bar{p}$ that have been obtained after analyzing 688.5~pb${}^{-1}$ of data taken at the BESIII experiment. They are compared and put into perspective to results from previous measurements in this channel. We discuss the channels $p\bar{p}\to e^{+}{e}^{-}$ and $p\bar{p}\to {\mu }^{+}{\mu }^{-}$ in terms of the few existing as well as future measurements, which the PANDA experiment will perform. Finally, we review several new theoretical models and phenomenological approaches inspired by the BESIII high precision results and then discuss their implications for a deeper understanding of the proton's structure and inner dynamics.

References in corpus (11)

• The size of the proton - closing in on the radius puzzle
• Measurement of the proton form factor by studying $e^{+}{e}^{-}\to p\bar{p}$
• Nucleon Electromagnetic Form Factors in the Timelike Region
• Unexpected features of e+e-->ppbar and e+e-->lambda-lambdabar cross sections near threshold
• Glue spin and helicity in proton from lattice QCD
• Periodic interference structures in the time-like proton form factor
• Time- and Spacelike Nucleon Electromagnetic Form Factors beyond Relativistic Constituent Quark Models
• Dispersion-theoretical analysis of the electromagnetic form factors of the nucleon: Past, present and future
• Study of the process $e^{+}{e}^{-}\to p\bar{p}$ via initial state radiation at BESIII
• New fit of time-like proton electromagnetic form factors from $e^{+}{e}^{-}$ colliders
• The fourth dimension of the nucleon structure: spacetime analysis of the timelike electromagnetic proton form factors

Cited by in corpus (1)

• The $\Sigma$ and $\Xi$ electromagnetic form factors in the extended vector meson dominance model