DUNE is one of the better particle physics acronyms. The Deep Underground Neutrino Experiment involves a large, sensitive detector which will indeed be deep underground - in the Sanford Lab at the Homestake goldmine in South Dakota – and will study neutrinos produced from a high-intensity beam of protons at Fermilab in Illinois. UK scientists from several universities are already deeply involved in the experiment, and Cambridge’s Prof. Mark Thomson is one of the two spokespeople who lead the experiment internationally.

The science of neutrinos is fascinating, with wide implications for our understanding of the universe and how it operates. Neutrinos are produced copiously in the Sun, and are the second most abundant particle in the universe. In the original conception of the “Standard Model” of particle physics, they were taken to be massless. The discovery that they actually have a - very tiny but non-zero - mass remains the only major modification forced upon the Standard Model since it was established. Fittingly, the first measurement leading to that discovery took place in the Homestake mine, which will now be reoccupied by one of the DUNE detectors. A goldmine in more than one sense.

The fact that neutrinos have mass has important implications. It affects their role in how large scale structures – galaxy clusters – formed in the universe after the Big Bang, for example. It may also have a profound impact upon why the universe is made of matter not anti-matter.

Most of the laws of physics are unbiased between matter and anti-matter. This means that equal amounts of the two should have been produced in the Big Bang, so where all the antimatter has gone is a bit of a mystery . Non-zero neutrino masses allow a quantum mixing between different types of neutrino, and this mixing could allow differences between their matter and anti-matter interactions. That in turn may go some way toward explaining the mystery of the missing antimatter. Seeing whether that is the case is one of the major goals of DUNE, as well as of other neutrino experiments around the world, including the proposed HyperKamiokande experiment in Japan.

The UK has a long-standing particle-physics partnership with the US, including the current Noνa neutrino experiment and precision muon experiments. There is significant support for the programme via CERN as well, something established in response to the European Strategy for Particle Physics. Prof. Christos Touramanis at the University of Liverpool is co-leader of the large-scale DUNE prototype activities at CERN.

Particle physics is a complex international endeavour; not only do the experiments address deep questions, the international pooling of expertise enables big leaps forward in technology.

On signing, the UK Science Minister, Jo Johnson said

Agreements like this also send a clear signal that UK researchers are outward looking and ready to work with the best talent wherever that may be

Perhaps a predictable emphasis given the current political situation, but it is true, important and worth saying. I for one am keen to see the results.

Jon Butterworth’s book “A Map of the Invisible: Journeys into Particle Physics” is released on 5 Oct 2017.