Our detector research and development targets innovative technology for neutrino experiments. This covers various diverse topics, from recent efforts into accelerator-based neutrino physics and neutrino astrophysics applications to specific neutrino mass searches using single and double beta decay.
My main focus is currently on Liquid Argon Detector Development.
Liquid Argon Detector Development
Particle physics aims to search for and identify all fundamental building blocks of matter in the universe (known as elementary particles), as well as discover their properties and interactions. In its century of existence, we have accumulated a vast amount of exciting knowledge about the sub-atomic world, culminating in the Standard Model, our current view of particle physics. The neutrino is one such building block and it is one of the least understood of all currently known particle species. There are three types or 'flavours' of neutrino: electron, muon and tau; Each has a very tiny mass and can interact with matter only very weakly. These properties mean that experiments aiming to detect neutrinos and investigate their nature have a challenging task.
The proposed project is to develop a neutrino detector that may be used by experiments attempting to probe and expose the character of the elusive neutrino. The detector could also reveal information about sources of neutrinos, for instance astrophysical or terrestrial sources. In order to peek in to the tiny world of neutrinos and gain a better understanding of their nature, a detector with superior capabilities to the human eye is required. The development of new technology for particle physics has historically had a huge impact on the health, economic well-being and security of 21st-century society.
Typically, detectors are relatively small, cheap and unobtrusive by design but their reliability and performance capabilities are generally pushed to the limit. The proposed detector differs only by way of its enormous physical size, several kilotons of mass in fact; This is for one single reason: neutrino interactions are pretty feeble. The larger the detection volume, the greater the probability of neutrino interactions, and consequently, the more information acquired about the mysterious particle. A detector capable of capturing the maximum amount of data requires an elegant design.
The detection material is a substance known as liquid argon. It is a gas at room temperature but becomes a liquid at extremely low temperatures, so requires cooling. It is safe, cheap and readily available. Liquid argon has been used in existing detectors so information is available but it has never been used at such large scales as proposed here. As neutrinos interact with the detection material, weak flashes of light occur in the medium which are then amplified using a device known as a thick gas electron multiplier (TGEM). This signal is essentially captured on a type of camera known as a silicon photomultiplier device (SiPM). The proposed new technology would then extract the maximum information on particle interactions with the detector material, i.e. the total energy involved, the individual tracks that the particles leave behind in the material and the position of the particle interaction.
Vast amounts of physics may be probed with such a device, for example, strong and weak neutrino sources would be visible as well as rare interactions of other particles. For modern society, affordable large area or volume radiation detection devices are highly sought after in medical physics, nuclear industry and security applications. Finally, it is worth mentioning that currently the UK has the lead in developing this new technology, having recently pioneered it. It is exciting to think of the possible major impact that it may have on particle physics as well as the inevitable spin-off's for society.