Pion exchange: the team used data from the HERA accelerator, which ran at DESY in Hamburg. (Courtesy: DESY) Gluons contribute around 30% to the total momentum of energetic pions, which is about three ...

The two-dimensional spatial distribution of mass due to gluons in the nucleon (left) and the pion (right), simulated at seven valence pion masses with lattice quantum chromodynamics. Understanding the ...

Pions are some of matter’s simplest particles. They’re built from the same building blocks as protons and neutrons, smaller particles known as quarks. While a proton is made from three quarks, only ...

Scientists can determine the mass of subatomic particles that are built from quarks by looking at the particles' energy and momentum in four-dimensional spacetime. One of the quantities that encode ...