First Direct Observation of Collider Neutrinos with the FASER Experiment - PRL Journal Club

Neutrinos are among the most abundant particles in the Universe, but they rarely interact with matter: trillions pass through us every second, but most of us will never have even a single one interact with the matter in our bodies. Nonetheless, scientists can study these particles using high-intensity neutrino sources and detectors that are large enough to overcome the rarity of neutrino interactions. In this way, neutrinos have been observed from the Sun, from cosmic-ray interactions in the atmosphere, from Earth’s interior, from supernovae and other astrophysical objects, and from artificial sources such as nuclear reactors and particle accelerators in which a beam of particles hits a fixed target. But no one had ever detected neutrinos produced in colliding beams. This feat has now been achieved by the Forward Search Experiment (FASER), located at the Large Hadron Collider (LHC) at CERN in Switzerland. Florian Bernlochner (University of Bonn) and colleagues sat down with the Physical Review Journal Club to discuss the team's exciting results, which were recently published in Physical Review Letters and summarized in Physics Magazine. Bernlochner and colleagues provided a short presentation of their experiment and observations, followed by a live question-and-answer session moderated by David Saltzberg, UCLA.