Science

Have you noticed that the universe is full of matter and surprisingly little antimatter? Why this is so is one of the main questions the scientists of the LHCb experiment hope to answer. I am one of them.

I am interested in applying machine-learning to particle physics. In particular tree based methods, bayesian optimisation and transfer learning.

I work for Ecole polytechnique fédérale de Lausanne as post-doc, previously I worked for CERN as a research fellow. Along side my research, I lead the team developing the simulation and reconstruction software for one of the experiment's detectors. Without our from first principles simulation we could not do any of our data analyses! I also think about how we can record as much data as possible by making use of modern machine learning techniques.

Before coming to CERN I was a particle physics graduate student with The University of Manchester. My research focused on properties of top quarks using the vast data set from the D0 detector at Fermilab's Tevatron near Chicago. I defended my thesis in December 2012

Publications

Here is a list of my top publications and other science related documents. My PhD thesis is linked to at the bottom as well. Take a look at the full list of my publications on INSPIRE.

LHCb VELO Upgrade Technical Design Report

PDF

I am the team leader for the simulation and reconstruction software project and was responsible for the Module layout and Performance chapters of the report.

Measurement of Leptonic Asymmetries and Top Quark Polarization in tt̅ Production

Phys.Rev. D87 (2013) 011103

I performed the whole analysis: writing the code to select events, compare simulation to data and perform the statistical analysis. Wrote the final paper and shepherded the paper through internal collaboration review.

Measurement of spin correlation in tt̅ production using dilepton final states

Phys.Lett. B702 (2011) 16-23

I wrote the code to select events, compare simulation to data and perform the statistical analysis, edited the paper and shepherded the paper through internal collaboration and journal review.

Measurement of spin correlation in tt̅ production using a matrix element approach

Phys.Rev.Lett. 107 (2011) 032001

I prepared the data and Monte Carlo samples, planned analysis strategies and lead discussions with theorists. Created the final figures used in the paper.

Evidence for spin correlation in tt̅ production

Phys.Rev.Lett. 108 (2012) 032004

I took part in planning and discussions in our four person team on extending our previous analysis to this new final state, lead interactions with theorists. I created the final figures used in the paper.

A measurement of the WZ and ZZ production cross sections using leptonic final states in 8.6 fb-1 of pp̅ collisions

arXiv:1201.5652

This analysis uses a multivariate classifier to identify electrons which I proposed and implemented, with efficiency gains of ~10% per electron over previous algorithms. These are the most precise WZ and ZZ cross section measurements at sqrt(s)=1.96TeV to date.

Thesis: Top Quark Spin Correlations and Leptonic Forward-Backward Asymmetries at D0

inspire entry

A summary of all my work as a PhD student, my thesis. Only print it off if you need a door stop, otherwise read it on your screen.

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