ProtoDUNE at CERN

The liquid argon time projection chamber is a type of particle detector that will dominate the future of neutrino physics. Huge tanks of liquid argon, at -186 C, will be placed in neutrino beams. When neutrinos collide with the argon, the products of the collisions ionise the argon atoms, leaving behind free electrons. A huge electric field, of hundreds of thousands of volts, is placed across the argon, dragging the free electrons towards planes of wires, called anode planes, where the electrons are converted into pulses of current that are read out from the detector. The beauty of these detectors is that they allow the neutrino interactions to be imaged with millimetre-scale precision, creating images of the interactions that allow the tracks of individual particles to be seen.

The aim of the ProtoDUNE project is to characterise how this liquid argon technology performs. We will build a liquid argon time projection chamber that will be placed in a particle beam at CERN. This particle beam will not contain neutrinos but will, instead, contain the sorts of charged particles that are produced in neutrino interactions - protons, pions, muons, etc. By observing how the ProtoDUNE detector responds to these particles, we will gain a much better understanding of how the future neutrino detectors will behave.

This project will result in the training of a number of PhD students and post-doctoral researchers in technological, software and analytic skills. These researchers will learn about cryogenics, electronics, software development, and analysis of large data-sets. Many of these researchers will go on to careers outside of academia, taking these invaluable skills with them.

As part of this project, we will be working with a number of companies to achieve our goals. These will primarily be mechanical engineering companies (in building the wiring machine), electronics companies (to build the PCBs) and cryogenics companies. We will continually exchange knowledge with these companies, as we develop the new technologies required to build a liquid argon time projection chamber.

This project is part of a longer-term effort to determine the neutrino mass hierarchy and look for a matter-antimatter asymmetry in the lepton sector, which may help to understand why we live in a matter-dominated universe. These big science questions are a hugely important part of a healthy society, and our quest to answer them is what inspires many young people to pursue degrees in STEM subjects.