proton

Why hasn’t matter fallen apart over billions of years? The mystery might start with protons. Scientists continue to conduct experiments that have yet detected proton decay but discovering it would reveal new insights into the fundamental laws of nature.

The CMS collaboration announced the observation of two photons creating two tau leptons in proton–proton collisions. This is the first time this process has been seen in proton–proton collisions using the precise capabilities of the CMS detector. It is also the most precise measurement of the tau’s anomalous magnetic moment and offers a new way to constrain the existence of new physics.

Fermilab’s MINERvA experiment was chosen as one of the nine runners up as part of the Physics World 2023 Breakthrough of the Year. The MINERvA research shows how information about the internal structure of the proton can be gleaned from neutrinos scattering from a plastic target.

From Big Think, June 22, 2023: Fermilab’s Don Lincoln discusses how the Universe is timeless and dimensionless from a photon’s viewpoint.

From Scientific American, March 16, 2023: Big news about a smaller size: MINERvA researchers used a new and entirely independent method to measure a proton’s radius. The team’s measurement of the proton’s radius was 0.73 femtometer, even smaller than the 0.84-femtometer electric charge radius. In either case, it is almost 10,000 times smaller than a hydrogen atom.