Standard Model Phenomenolgy.

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Keith Hamilton's research concerns the development of high precision Monte Carlo simulations of collider Physics processes. These facilitate discovery and interpretation of new physics at the Large Hadron Collider (LHC). While precision simulations may not be needed to claim a discovery, e.g. if new physics appears as a clear `bump' in a smooth distribution, (as did the Higgs boson), in many scenarios, such as supersymmetry, signals are expected to manifest as subtle distortions in the shapes of distributions. An accurate understanding of the Standard Model background, subject to all experimental cuts, is then unavoidable for claiming a discovery, or setting exclusion limits. Precision simulations are also essential to determine what it is that has been found. The recently discovered 125 GeV mass Higgs boson is the prime example of this. In 2012-2013 Hamilton and collaborators in Milan and Oxford developed the world's most accurate simulation of Higgs boson production. This simulation is now used by default by the ATLAS and CMS collaborations, appearing in their publications confronted with measurements to probe Higgs boson properties. In recent years Hamilton's work has shown how to extend the methodology behind that cutting-edge simulation to an important wider range of LHC reactions. In the coming years Hamilton will work as part of a new team, comprising three other world-class researchers, to extend the most central, parton shower, component of general purpose Monte Carlo event generators -- the most widely used theoretical tools in particle physics. General purpose event generators are at the heart of the way in which collider physics is carried out, impacting on the whole community. Thorne's work is complementary to that of Hamilton. It involves the precise details of the initial state appearing in hadronic particle collisions. At hadron colliders, e.g. the Large Hadron Collider (LHC), the particle beam is effectively made up of the fundamental particles inside the proton - quarks and gluons, generically known as partons. Predictions for Standard Model processes, and potentially those of new physics, require the precise partonic composition of the hadrons in terms of both the energy scale of the scattering process (e.g., the mass of a particle produced) and the momentum fraction of the incoming proton carried by the parton. Thorne is the lead member of an established PDF group that provides one of sets of parton distribution functions (PDFs) used as standard by both the experimental and theoretical analyses at the LHC and other high energy particle physics experiments. The approach is continually refined, both in terms of theoretical sophistication, and by inclusion of data which become available and due to increased precision or different sensitivity to PDFs, lead to further PDF constraints. Thorne's work will lead to improved PDF determination, providing updated PDFs for universal use, and he will also investigate the consequences of any changes. This will lead to a better understanding of current and upcoming measurements, and will also influence planning for future high energy particle physics experiments. Additionally, Thorne is a core member of the PDF4LHC working group (a member of the steering committee since the inception, and one of the main drivers and organisers) which provides recommendations for use of PDF sets at the LHC and acts as a direct liason to the LHC experimental community.Both Hamilton and Thorne are involved in ever increasing precision for calculations at the LHC, which is particularly essential in order maximise the potential of the LHC, particularly given the current situation of no clear signals of new physics, but continual appearance of unprecedented variety and precision of Standard Model tests. Both will provide expertise in interpretingany deviations which could be the first sign of Beyond the Standard Model (BSM) Physics.