First results from FASER(v): Observation of collider neutrinos and a new search for Dark Matter

There are a billion ghost-like particles passing through an area the size of your thumbnail every second. These neutrinos play a crucial role in our understanding of the Universe, from how the Sun shines, to exploding supernovae. There are also lots of open questions about neutrinos - we know they have mass, but the Standard Model predicts them to be massless. FASER is adding to the long history of neutrino physics by being the first experiment to observe directly neutrinos produced in a collider (the Large Hadron Collider). Previous examples of neutrino detection from different sources have led to profound insights across the fields of particle physics, nuclear physics, and astrophysics. New measurements from FASER open up a new window to look for beyond the Standard Model physics.

FASER stands for “ForwArd Search ExpeRiment” so one of its other aims is to search exotic long-lived new particles that are candidates to explain the existence of Dark Matter. If they exist, these exotic particles would be produced in collisions inside the ATLAS detector and be detected nearly 500m away in FASER. FASER is able to look for a type of these Dark Matter particles that no experiment until now has had sensitivity to.