Particle Physics Consolidated Grant 2019

Particle physics seeks to understand the Universe, its birth, evolution & fate in terms of the interplay of elementary particles (quarks & leptons), the fundamental forces (strong, electromagnetic & weak forces, & gravity) and force-particles that mediate them (photons, W/Z, gluons & gravitons) and the recently discovered Higgs particle that gives elementary particles mass. The last thirty years have seen the development of a theoretical framework, the Standard Model, in which almost all particle-physics data can be explained. But the model is incomplete. It explains what we encounter on Earth but studies of the cosmos suggest the presence of mysterious dark matter that holds galaxies together and more mysterious dark energy that is driving galaxies apart at an ever increasing rate. There are so many mysteries! There has never been a better time to be a particle physicist. Oxford's research will advance significantly our understanding of whatever "new-physics" theory will emerge to replace the Standard Model by providing the data to guide the theoretical work to develop it. The Large Hadron Collider (LHC) reproduces the conditions within a million millionth of a second of the Big Bang. Oxford plays a major role in ATLAS and LHCb. These experiments have the potential to completely revolutionise our understanding of the universe. In ATLAS, Oxford physicists participated in the exciting discovery of the "Higgs particle", which makes matter matter by giving it mass. The Higgs particle is like a curtain; now that we have found the Higgs we can draw back the curtain to see a new world. Accordingly, we are studying it in great detail. We are also searching for particles with "supersymmetry" (SUSY), a theory that would provide a solution to "dark-matter" that makes up about 80% of matter in the Universe; and ATLAS is searching for hidden extra spatial dimensions. Oxford physicists on LHCb strive for a better understanding of the origin of the matter-antimatter asymmetry in the Universe by studying subtle differences in the behaviour of quarks & antiquarks - "CP-violation". This asymmetry permits us to exist. Over the next decade, the LHC will upgrade to higher energy & intensity so detector improvements will be made for ATLAS & LHCb during this grant. The upgraded detectors will take particle physics to an unprecedented level of sensitivity for the nearly inevitable new-physics observations. Throughout our work we use powerful computing resources and develop cutting-edge analysis tools that are necessary for the extraction of important discoveries from vast volumes of data. We participate in high-precision experiments complementary to the large experiments at the LHC. LZ addresses one of the most important questions in particle physics & cosmology: a search for dark matter; a candidate is the lightest SUSY particle. Mu3e searches for new physics mediated by very heavy particles that would not be visible at the LHC but are expected in many theoretical models including SUSY. LSST will measure how quickly the expansion of the universe is speeding up due to the mysterious dark energy that represents 75% of all energy in the universe and acts like anti-gravity pushing galaxies apart. Through T2K, SK, HK, DUNE, & future projects, Oxford aims to understand the elusive neutrino, its "oscillation" from one type to another and whether there is a difference between neutrino and anti-neutrino properties - "CP-violation". SNO+ will measure other properties of the neutrino, e.g. whether or not it is its own antiparticle. Throughout, Oxford will continue to develop & enhance capabilities in mechanical & electronic design so that we retain the ability to construct the most sophisticated apparatus for our experiments. We will retain our world-leading role for scientific excellence & major state-of-the-art detector construction in particle physics for the future. These are exciting times for particle physics, and Oxford is playing a major role.