# Collider Physics

We are at a decisive moment for deepening our understanding of the Standard Model of particle physics. Experimental data recently established the existence of the Higgs boson, and a new energy frontier is being explored at the Large Hadron Collider. This experimental data challenges theorists to keep up with theoretical understanding as detailed as experimental precision. It's a golden age for particle physics, and our group is enjoying it!

The Large Hadron Collider (LHC) basically operates by accelerating proton bunches in opposite directions around a ring and colliding them at extremely high energies. This allows us to probe nature at the energy scale of the collision, for example through producing massive particles (such as the Higgs boson.) Theoretical collider physicists work on calculating the predictions of the standard model for these processes. These predictions are necessary so that we can determine if some phenomenon observed at the LHC happened because of physics we understand - in the sense that the Standard Model predicts it - or if we need some new physics beyond the standard model.

The Standard Model is complicated, and so the calculations necessary for predicting LHC phenomena are quite involved. Therefore the calculations are typically divided up into various different parts which must be interfaced together to get a complete prediction. Our group in Edinburgh has considerable expertise in the major parts of this pipeline towards prediction. As part of an international software development project, NNPDF, we have developed a neural-network method to parametrise Parton Distribution Functions, crucial for understanding physics at hadron colliders without systematic theoretical bias. We also calculate theoretical predictions for high-energy processes at the LHC which produce collimated jets of energy for comparison to LHC data through HEJ. On the more analytic side, we are leading a major effort aimed at understanding the infrared singularities of QCD amplitudes. Studying the structure of these singularities is important both from a theoretical perspective, and from the pragmatic one of collider phenomenology. Infrared singularities provide the key to soft-gluon resummation, which is essential for precise predictions. Finally, we also work on deepening our understanding of the structure of the Standard Model. Recently, there have been several big advances in our ability to calculate processes which is based on a deeper understanding of the physics of the process. This has opened up the possibility of matching experimental progress to the next level of precision.

## PhD project opportunities in Collider Physics

## People in Collider Physics

Telephone numbers in the list below are shown as UK numbers. Callers from outside the UK should remove the leading zero and use the UK country code (+44).

Name | Position | Contact details | Location | Photo |
---|---|---|---|---|

Academic staff | ||||

Richard Ball | Professor | r.d.ball [at] ed.ac.uk | JCMB 4420 | |

Luigi Del Debbio | Professor | luigi.del.debbio [at] ed.ac.uk | JCMB 4418 | |

Einan Gardi | Director of Higgs Centre for Theoretical Physics | einan.gardi [at] ed.ac.uk | JCMB 4416 | |

Maxwell Hansen | UKRI Future Leaders Fellow | maxwell.hansen [at] ed.ac.uk | JCMB 4403 | |

Franz Herzog | UKRI Future Leaders Fellow | fherzog [at] ed.ac.uk | JCMB | |

Donal O'Connell | Professor | Donal.O'Connell [at] ed.ac.uk | JCMB 4405 | |

Jenni Smillie | Reader | j.m.smillie [at] ed.ac.uk | JCMB 4411 | |

Roman Zwicky | Professor | rzwicky2 [at] ed.ac.uk | JCMB 4415 | |

Research staff | ||||

Roy Stegeman | Postdoctoral Research Associate | r.stegeman [at] ed.ac.uk | JCMB 4311 |