Lancaster researchers are among an international team of scientists at the U.S. Department of Energy's Fermi National Accelerator Laboratory (Fermilab) to identify their first neutrinos.

Neutrinos are abundant but hard to detect particles with an intriguing ability to change ‘flavour’ between the three known types - muon, electron and tau.

This milestone marks a crucial step in the quest to uncover a potential fourth type of neutrino - a discovery that could reshape our understanding of the universe.

Part of a global collaboration involving 250 physicists and engineers from the UK, Brazil, Spain, Switzerland, and the US, the Short-Baseline Near Detector (SBND) project is a critical part of the Short-Baseline Neutrino program at Fermilab.

The Short Baseline Neutrino Program at Fermilab will perform searches for neutrino oscillation and look for evidence that could point to this fourth neutrino.

David Schmitz, co-spokesperson for the SBND collaboration, said: “It isn’t every day that a detector sees its first neutrinos. We’ve all spent years working toward this moment and this first data is a very promising start to our search for new physics.”

Thanks to funding from the Science and Technology Facilities Council (STFC), researchers from universities across the UK are playing a pivotal role as founding members, contributing to the design, construction, commissioning, and future physics research of the detector.

Lancaster researchers helped provided crucial evidence on the behaviour of the detector elements in cryogenic temperatures which helped to inform the facility.

Professor Jaroslaw Nowak of Lancaster University’s Physics Department is the SBND UK Principal Investigator and the Chair of the SBND Insitutional Board.

He said: “Seeing the first neutrino interaction in the SBND detector is a sign of a new era for us; we now redirect our efforts to answer many unresolved questions with the data we collect in the next few years."

Lancaster University has a substantial number of researchers working at SBND undertaking different research roles. The primary goal is to research a new type of particle called sterile neutrinos and to precisely measure the standard neutrinos' interaction with matter.

Professor Nowak, along with PhD student Bethany McCusker, is searching for rare neutrino interaction processes that produce particles called hyperons. Dr Andrew Blake and Dr Dominic Brailsford are developing sophisticated software to detect the traces of the neutrino interaction detected by the SBND detector.

They are also working with Dr Henry Lay (now at the University of Sheffield) and a PhD student Rachel Coackley on precision measurements of neutrino interactions, with a focus on some of the most common interaction channels.

The Standard Model of particle physics, which explains how the universe operates at its most fundamental level, serves as the gold standard for everything from high-intensity particle collisions to rare decays.

The discovery of a fourth type of neutrino would challenge this model, forcing a rewrite that could have significant implications for our understanding of dark matter and the universe’s evolution.

Ten UK universities are involved in the experiment – Lancaster University, Imperial, Edinburgh, Liverpool, Manchester, Oxford, Sheffield, Sussex, UCL, and Queen Mary University of London.