Institute for Particle Physics Phenomenology, Oct 2018 - Sept 2020

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Particle physics research informs us about the nature of matter onvery small scales. As we step down the length scales below the lengthscale of the atom, 10^(-10) meters, and past the length scale of theatomic nucleus, 10^(-15) meters, we enter the realm of particlephysics. In this realm there are three well identified interactions.First, the strong interactions, which are responsible for the bindingof quarks and gluons to produce protons, neutrons and other particlescollectively called hadrons. Second, the electroweak interactions,responsible both for the radiation of photons (light) from matter andthe radiation of the carriers of the weak force, the W and Z bosons,discovered at CERN in the 1983. Third, the interactions of the Higgsbosons. The Higgs boson was discovered at CERN in 2012.The interactions of all of these ingredients are controlled by amathematical structure, known as the Standard Model (SM) gauge theoryof electromagnetic, weak and strong interactions. This theory has sofar withstood all the challenges posed by various accelerators, ofwhich the latest and most energetic is the LHC. The SM is confirmed--- with the unification of electromagnetism and weak interactionsproved and tested to one part per mille. Strong interaction effectshave been tested to the per cent level. The quarks, the ingredients of the hadrons, come in six different typeswhich are referred to as flavours. Flavour phenomena have contributedas much as the gauge principle in shaping the overall structure of theSM and it is the existence of flavours that gives the SM its familyand generation structure. In the quark sector the SM description offlavour phenomena and the CKM picture of mixing and CP violation isnow verified at the few per cent level. In the lepton sector, theflavours of leptons are the electron, the muon and the tau and theirassociated neutrinos. The observation of neutrino oscillations, andthe consequence that neutrinos have mass, calls for an extension ofthe SM. Detailed examination of the charged and neutral leptons is of increasing importance.In 2015, the Large Hadron Collider (LHC) started to accelerate andcollide protons at much higher energies than ever before, 13 TeV. Thehigh energy reach of the LHC will allow the detailed study of theHiggs boson and exploration of TeV scale physics. However, the LHCexperiments are significantly more complex than any previous particlephysics experiment. Identifying the nature of physics at the TeV scalewill require intense collaborative efforts between experimentalistsand theorists. On the theoretical side, high-precision calculations ofSM processes are needed to distinguish possible signals of new physicsfrom SM backgrounds. Possible hints of new physics need to be comparedwith different models of physics beyond the SM in order to disentanglethe underlying structure of TeV-scale physics. The IPPP has alreadyestablished close connections with the UK and internationalexperimental groups and is perfectly placed to help maximise the UKcontribution to understanding the LHC data.Once the energy scale of new physics is identified, there will be astrong effort in planning and designing the next generation ofparticle physics experiments. The IPPP will continue its role inassessing the physics potential and the design of future accelerators.The next decade promises to be pivotal in our understanding of themicroscopic world. The IPPP will address fundamental questions aboutelectroweak symmetry breaking, the structure of space-time, flavourphysics and CP violation, neutrinos and lepton-flavour violation, andhow particle physics connects with astrophysics and cosmology.