Neutrinos are tiny and neutrally charged particles accounted for by the Standard Model of particle physics. While they are estimated to be some of the most abundant particles in the universe, observing them has so far proved to be highly challenging, as the probability that they will interact with other matter is low.
Neutrinos are tiny and neutrally charged particles accounted for by the Standard Model of particle physics. While they are estimated to be some of the most abundant particles in the universe, observing them has so far proved to be highly challenging, as the probability that they will interact with other matter is low.
To detect these particles, physicists have been using detectors and advanced equipment to examine known sources of neutrinos. Their efforts ultimately led to the observation of neutrinos originating from the sun, cosmic rays, supernovae and other cosmic objects, as well as particle accelerators and nuclear reactors.
A long-standing goal in this field of study was to observe neutrinos inside colliders, particle accelerators in which two beams of particles collide with each other. Two large research collaborations, namely FASER (Forward Search Experiment) and SND (Scattering and Neutrino Detector)@LHC, have observed these collider neutrinos for the very first time, using detectors located at CERN’s Large Hadron Collider (LHC) in Switzerland. The results of their two studies were recently published in Physical Review Letters.
« Neutrinos are produced very abundantly in proton colliders such as the LHC, » Cristovao Vilela, part of the SND@LHC Collaboration, told Phys.org. « However, up to now, these neutrinos had never been directly observed. The very weak interaction of neutrinos with other particles makes their detection very challenging and because of this they are the least well studied particles in the Standard Model of particle physics. »
The FASER and SND@LHC collaboration are two distinct research efforts, both utilizing the LHC at CERN. Recently, these two efforts independently observed the first collider neutrinos, which could open important new avenues for experimental particle physics research.
The FASER collaboration is a large research effort established with the goal of observing light and weakly interacting particles. FASER was the first research group to observe neutrinos at the LHC, using the FASER detector, which is positioned over 400m away from the renowned ATLAS experiment, in a separate tunnel.
