An Early-Stage Perspective of The COMET Experiment

by Ben Krikler

Muon decay in the Standard Model requires the emission of two neutrinos thanks to the concept of Lepton Flavour conservation. But this conservation is difficult to motivate theoretically and indeed, given neutrino oscillations, is known to be violated in the Standard Model albeit at a very small level. The COMET experiment is one of a handful of projects hoping to demonstrate Charged Lepton Flavour Violation, searching for COherent Muon to Electron Transitions, where a muon converts to an electron in the presence of an atomic nucleus (aluminium for COMET), without neutrino emission. This process is particularly attractive from an experimental perspective since the signal of a single 105 MeV electron is robust against accidental backgrounds and the Standard-Model background is so vanishingly small. In this seminar I will give an overview of the process of muon-to-electron conversion and the COMET experiment itself, with which Imperial and the UK have been involved since its inception. COMET Phase-I is currently under construction and due to begin data taking in JFY 2018. Whilst this stage aims for a factor 100 improvement on the current limit to around 3x10^-15, Phase-II will go a further two orders of magnitude and run at the beginning of the next decade. Setting such stringent limits produces many significant design challenges. These and the progress to their solutions will be presented, as well as recent developments in facility, beam-line and detector construction.