Science at Jefferson Laboratory: The amazing world of quarks and gluons

  • March 8, 2023, 4:00 pm US/Central
  • David Dean, Jefferson Lab
  • Chris Stoughton
  • Video

Nuclei make up 99% of the mass in the visible universe, and all but the lightest nuclei are produced in cataclysmic stellar events such as supernova explosions and neutron star mergers. Every proton (and neutron) within all nuclei is governed by QCD, the theory of quarks, gluons, and their interactions. Understanding the amazing world inside a proton requires tremendous technical capabilities embodied in large accelerator facilities and advanced detector technology, as found at the world-class facilities of Jefferson Laboratory. These capabilities enable us to understand how QCD supports the dynamical generation of bound states with a rich variety as seen from data.  Interestingly, the more closely one peers into a proton (with higher-energy electrons), the more complex the emergent phenomena one measures. Tying these measurements to theory often requires models informed by LQCD calculations. Furthermore, JLab’s experimental capabilities, using parity violation, have recently enabled a precise measurement of the thickness of the neutron skin in Pb which has implications in the astrophysics associated with neutron-star mergers. This interplay is but one demonstration of how the world of the small, even at the proton level, affects the most violent of collisions in the universe.