Neutrinos
Neutrinos are light, electrically-neutral elementary particles that make up the least-understood part of the Standard Model of particle physics. Facilities like DUNE (the Deep Underground Neutrino Experiment) study neutrinos produced in the Fermilab collider as well as neutrinos arriving from cosmic events. Project 8 will measure neutrino mass by looking at neutrinos emitted when tritium decays. The CMB Stage 4 telescopes will use cosmological data to constrain the number of neutrinos and their mass. Many other neutrino facilities focus on detecting neutrinos produced in astrophysical processes, including ANITA, ARA, BEACON, GRAND, IceCube, PUEO, and RNO-G. These cosmic neutrinos can carry key information, along with electromagnetic radiation and gravitational waves, in "multi-messenger" detections of dynamic events in the universe.
