My past research interests have been in three areas of experimental high energy particle physics. Firstly measurements of the structure of the proton and developing our understanding of the strong nuclear force as embodied in the theory of quantum chromodynamics (QCD). Secondly precision measurements of the W-boson, the particle responsible for mediating the weak nuclear force, in particular precision measurements of its mass and lifetime. Thirdly, developing state-of-the-art computer software solutions and high speed electronics for data processing and reduction. This research has been based at two particle accelerators in Hamburg (HERA) and Chicago (Tevatron). I was the UK PI for the CDF experiment from 2002-2013 and CDF's Standard Model/EWK convenor from 1998-2000 and 2008-2013.
My present research is as part of two muon experiments and a cavity-based axion search experiment using quantum technologies . I am presently the UK PI for the g-2 and Mu2e experiments.
The Fermilab Mu2e experiment is hoping to be the first experiment to observe a lepton-flavour violating, neutrinoless transition of a muon into an electron. Such an observation would be certain to signal new physics beyond our present understanding of fundamental particles since in the Standard Model the rate of this decay is approximately 10-50 that of the usual muon decay producing two neutrinos.
The Fermilab g-2 experiment has made the world's most precise measurement of any quantity at a particle accelerator: the muon's anomalous magnetic moment. This presently differs from the SM predictions by 2 to 5 standard deviations depending on the methodology used to determine the SM value. Subsequent measurements and refinements in the SM prediction will establish unambigiously whether this is a sign of new physics or not.
To explain the fact that nobody has measured a finite neutron or proton electric dipole moment requires a yet-to-be-observed dynamical mechanism. Without this mechanism, the quarks inside protons and neutrons are required to be aligned, unnaturally, to one part in 10 billion. At the heart of this mechanism is the last undiscovered particle in the Standard Model: the axion. The axions presence is inferred through the emission of microwaves in a resonant cavity within a magnetic field. The power in these microwaves is tiny: a yocto (10-24) watt, but recent advances in quantum technology make detection possible. We are building a proof-of-principle axion detector at Manchester.
A list of my research publications can be found here and the most significant ones to which I have contributed here .