A Programme of Technology, Astrophysics and Cosmology in Cardiff, 2022-2025

Astronomers try to answer a wide range of questions, from fundamental ones, such as how stars and galaxies are formed and questions about the structure and evolution of the universe itself, to more detailed questions about the physical and chemical processes occurring in astronomical objects. A powerful way of trying to answer some of the most important ones is to make observations in the submillimetre waveband, one of the newest branches of astronomy. The births of stars and galaxies, for example, occur in huge clouds of gas and dust, and the dust - tiny solid fragments in interstellar space - hides the births from traditional optical telescopes like the Hubble Space Telescope. With submillimetre telescopes, however, it is possible to observe radiation from the dust itself, allowing astronomers to observe the very earliest stages in the lives of stars and galaxies. Submillimetre astronomy is one of our specialities in Cardiff, with our group containing both astronomers that use submillimetre telescopes but also scientists that build novel cameras and other devices that work in this waveband - technology that also has many uses outside astronomy. In this proposal we ask for funds from the UK taxpayer to support our research. Much of this research involves using or building submillimetre instruments, but some of the projects we propose will use telescopes in other wavebands or use powerful computers to simulate the processes involved in the birth of a star or the formation of a galaxy. The questions we will try to answer include many of the most important ones. One of the surprising things about planets like ours is that they exist at all, because centimetre-sized solid chunks around a star are likely to be destroyed before they coalesce to form bigger chunks and eventually planets. We will use radio observations to search for chunks of this size in the disks of dust around newly formed stars, with the aim of understanding how small rocky planets like our own were formed, and in another project we will use a new balloon observatory to study the other end of the planetary spectrum - the giant 'hot Jupiters' that have been discovered around nearby stars. We propose several projects to investigate the formation of stars, both the stars that are forming around us today and a special population of stars with very few heavy elements that astronomers think formed just after the Big Bang, using a mixture of observations and computer simulations. We propose two project that will study supernovae, the titanic explosions that occur when a massive star collapses at the end of its life. One project will investigate the formation of dust grains and molecular gas within a supernova explosion, the other the recently discovered superluminous supernovae, up to 100 times more luminous than the standard kind. Again using a mixture of observations and computer simulations, we propose several projects to study galaxies, including a study of the Andromeda Galaxy, the nearest big galaxy, an investigation of the super-massive black holes at the centres of nearby galaxies, a computer simulation of the gas flows around a galaxy, and a project to find more examples of very distant galaxies, which we are seeing only shortly after the Big Bang and that are being highly magnified by the gravity of close galaxies. More examples of these highly magnified galaxies is important because the magnification means that we can study the way galaxies are formed in great detail. We also propose two technical projects, one to develop kinetic inductance detectors, a kind of detector that our group largely discovered and which makes possible revolutionary new instruments, and one to develop further 'meta-materials', a kind of material that makes possible novel components for instruments, such as flat lenses, and which our group has used to make the filters for all submillimetre telescopes, on the ground and in space, over the last 30 years.