Ciaran Williams, PhD

257 Fronczak Hall
(716) 645-5901
ciaranwi@buffalo.edu
Website

• MSci, Theoretical Physics, University of Durham – 2006
• PhD, Physics, University of Durham – 2010
• Postdoctoral Research at Fermilab and the Niels Bohr Institute

High Energy Theory, HEPCOS

High energy theory, Collider physics

My research primarily involves performing calculations at high precision in Quantum Field Theories, which make up the Standard Model of particle physics and its extensions. Such calculations are mandatory given the excellent performance and superb data coming from CERN's Large Hadron Collider (LHC). High precision calculations are obtained from a perturbation theory in the coupling constants of a particular field theory, and result in loop integrals. These loop integrals require detailed calculation, we have just about mastered one-loop processes for the LHC, but have a long way to go obtain mastery at two-loops and beyond. There predictions will allow the theoretical uncertainty at the LHC, to match or better the experimental precision, and as such allow us to search for small effects which arise from unknown physics.

One such effect may be caused by Dark Matter (DM) production. There is an overwhelming abundance of evidence for the cosmological existence of DM, however we have yet to understand it from a particle physics point of view. The properties of DM are suggestive of potential interactions around the scales which the LHC can probe, if this is the case the LHC may be able to directly produce DM in the lab. Such an exciting prospect would fundamentally alter our view of nature. In order to maximize the potential of the LHC it is crucial for theorists and experimentalists to work together. The common ground between both worlds is known as phenomenology, and is an area I particularly enjoy working in.

• Wu-Ki Tung Award: Early-Career Research on QCD, 2016
• NSF CAREER Award, 2017
• UB Young Investigator Award, 2018

• Bounding the Higgs width at the LHC using full analytic results for gg -> eemumu, John M. Campbell, R. Keith Ellis, Ciaran Williams, arXiv:1311.3589 [hep-ph], JHEP 1404 (2014) 060.
• Next-to-Leading Order Predictions for Dark Matter Production at Hadron Colliders, Patrick J. Fox, Ciaran Williams, arXiv:1211.6390 [hep-ph], Phys.Rev. D87 (2013) 5, 054030.
• The Matrix Element Method at Next-to-Leading Order, John M. Campbell, Walter T. Giele, Ciaran Williams, arXiv:1204.4424 [hep-ph], JHEP 1211 (2012) 043.
• Gluon-Gluon Contributions to W+ W- Production and Higgs Interference Effects, John M. Campbell, R.Keith Ellis, Ciaran Williams, arXiv:1107.5569 [hep-ph], JHEP 1110 (2011) 005.
• Vector boson pair production at the LHC John M. Campbell, R.Keith Ellis, Ciaran Williams, arXiv:1105.0020 [hep-ph], JHEP 1107 (2011) 018.
• Hadronic production of a Higgs boson and two jets at next-to-leading order, John M. Campbell, R.Keith Ellis, Ciaran Williams, arXiv:1001.4495 [hep-ph], Phys.Rev. D81 (2010) 074023.
• One-loop Higgs plus four gluon amplitudes: Full analytic results, Simon Badger, E.W. Nigel Glover, Pierpaolo Mastrolia, Ciaran Williams, arXiv:0909.4475 [hep-ph], JHEP 1001 (2010) 036.

For a complete list of publications, please see Inspire.