Precision spectroscopy of positronium

Project ID: 2531bd1697

(You will need this ID for your application)

Research Area(s): Physics

UCL Lead department: Physics and Astronomy

Project Summary:

The positronium spectroscopy group (PSG) at UCL perform spectroscopic measurements of the matter-antimatter atomic system positronium (Ps, the bound state of a positron and an electron). Precision optical and microwave spectroscopic measurements of Ps atoms are used to test advanced quantum electrodynamics (QED) theory, and also to probe for physics beyond the standard model. These experiments are tests of fundamental physics and may in the long-term help to understand the matter-antimatter asymmetry of the Universe (i.e., why is the Universe apparently composed only of matter?). The experiments are conducted using a positron beam located in the physics department, with the aim of measuring the Ps energy level structure. with high precision. Working on this project will involve interaction with the PSG team, and will provide direct experience in a broad range of experimental techniques, including ultra-high vacuum, cryogenics, hands on operation of lasers and microwave radiation sources and optics, beam and ion trapping techniques, gamma ray detection, and plasma physics.

The project involves performing cutting edge Ps spectroscopy, and the development of new interferometric measurements that are expected to push the precision beyond the current QED theory limits. It also includes the application of new quantum-sensing methods to further increase the obtainable precision in the Ps spectroscopy, improve sensitivity to possible new physics, and facilitate a wider programme of tests of discrete symmetries (specifically CP violation in the lepton sector) and investigations of quantum entanglement in annihilation gamma ray photons. The work also involves developing advanced computer simulations (typically using PYTHON) to model the experiments. No prior experience in any of these areas is required.

More information about the group, as well as a list of publications, can be found at https://antimattergravity.com/

For informal enquiries contact Professor David Cassidy d.cassidy@ucl.ac.uk