We highlight the progress, current status, and open challenges of QCD-driven physics, in
theory and in experiment. We discuss how the strong interaction is intimately connected to a …

The extremely precise extraction of the proton radius obtained by Pohl et al. from the
measured energy difference between the 2 P and 2 S states of muonic hydrogen disagrees …

The proton is the primary building block of the visible Universe, but many of its properties—
such as its charge radius and its anomalous magnetic moment—are not well understood …

1.1. Background This article reports work carried out under the auspices of the Committee
on Data for Science and Technology (CODATA) Task Group on Fundamental Constants. 1 It …

Accurate knowledge of the charge and Zemach radii of the proton is essential, not only for
understanding its structure but also as input for tests of bound-state quantum …

1.1. Background This paper gives the complete 2006 CODATA self-consistent set of
recommended values of the fundamental physical constants and describes in detail the …

We review the spectrum and electromagnetic properties of baryons described as relativistic
three-quark bound states within QCD. The composite nature of baryons results in a rich …

The proton size, specifically its charge radius, was thought known to about 1% accuracy.
Now a new method probing the proton with muons instead of electrons finds a radius about …

Laser spectroscopy of muonic atoms has been recently used to probe properties of light
nuclei with unprecedented precision. We introduce nuclear effects in hydrogen-like atoms …

This paper gives the 2002 self-consistent set of values of the basic constants and conversion
factors of physics and chemistry recommended by the Committee on Data for Science and …