This report describes the physics case, the resulting detector requirements, and the evolving
detector concepts for the experimental program at the Electron-Ion Collider (EIC). The EIC …

Abstract This White Paper aims at highlighting the important benefits in the science reach of
the EIC. High luminosity operation is generally desirable, as it enables producing and …

Elastic electron–proton scattering (e–p) and the spectroscopy of hydrogen atoms are the two
methods traditionally used to determine the proton charge radius, r p. In 2010, a new method …

The cross section for prompt antiproton production in collisions of protons with an energy of
6.5 TeV incident on helium nuclei at rest is measured with the LHCb experiment from a data …

The aim of this report is to give basic notions on electromagnetic hadron form factors (FFs),
as they are understood at the present time, to summarize and analyze the present …

The OLYMPUS Collaboration reports on a precision measurement of the positron-proton to
electron-proton elastic cross section ratio, R 2 γ, a direct measure of the contribution of hard …

We review recent theoretical and experimental progress on the role of two-photon exchange
(TPE) in electron–proton scattering at low to moderate momentum transfers. We make a …

The ratio of the elastic e+ p to ep scattering cross sections has been measured precisely,
allowing the determination of the two-photon exchange contribution to these processes. This …

Proper interpretation of past, current, and future data on lepton-nucleus reactions requires a
clear separation between quantum electrodynamics and strong interaction effects inside the …

A proton is a bound state of a strong interaction, governed by Quantum Chromodynamics
(QCD). The electric charge radius of a proton, denoted by r E p, characterizes the spatial …