visible matter tagged posts

New results on nucleon structure. Two independent studies have illuminated unexpected substructures in the fundamental components of all matter. Preliminary results using a novel tagging method could explain the origin of the longstanding nuclear paradox known as the EMC effect. Meanwhile, authors will share next steps after the recent observation of asymmetrical antimatter in the proton.

Both groups will discuss their experiments at DOE’s Thomas Jefferson National Accelerator Facility and Fermilab during the 2021 Fall Meeting of the APS Division of Nuclear Physics.

One study presents new evidence on the EMC effect, identified nearly 40 years ago when researchers at CERN discovered something surprising: Protons and neu...

An overview of the NA64 experimental set-up at CERN. NA64 hunts down dark photons, hypothetic dark matter particles. Credit: Maximilien Brice/CERN

One of the biggest puzzles in physics is that 85% of the matter in our universe is “dark”: it does not interact with the photons of the conventional electromagnetic force and is therefore invisible to our eyes and telescopes. Although the composition and origin of dark matter are a mystery, we know it exists because astronomers observe its gravitational pull on ordinary visible matter such as stars and galaxies.

Some theories suggest that, in addition to gravity, dark matter particles could interact with visible matter through a new force, which has so far escaped detection...