The AEgIS experiment (Antihydrogen Experiment: Gravity, Interferometry, Spectroscopy) aims to measure the gravitational fall of an antihydrogen pulsed beam.
It is understood that matter and antimatter were created equally in the Big Bang, and when they meet, they annihilate each other. However, we live in a universe dominated by matter. Physicists in CERN’s Antimatter Factory are creating small quantities of antimatter and conducting a range of experiments to learn more about its properties and answer the question ‘what happened to the antimatter?’.
AEgIS is one of the very few experiments that use antiprotons to directly investigate the properties of antimatter by exploiting the charge exchange reaction between cold antiprotons and excited Rydberg-positronium, the bound state of an electron and a positron, in order to generate Rydberg-antihydrogen.
The AEgIS experiment involves physicists from a number of countries in Europe as well as from India. The University of Liverpool is the first UK university to join.
Amongst the research challenges that AEgIS will address over the next few years are the development of next-generation positron/positronium converter targets, the formation and transport of pulsed antihydrogen beams with unprecedented intensity and Stern-Gerlach type experiments on a cold positronium beam.
AEgIS spokesperson Dr Michael Doser said: “I am delighted to welcome Liverpool as a new member in the AEgIS collaboration! We look forward to pushing the limits of low energy antimatter physics with the UK group.”
Cockcroft Institute researchers have closely collaborated with CERN on low energy antimatter R&D for more than a decade. This includes studies into the beam dynamics at the Antiproton Decelerator (AD) and the new ELENA low energy storage ring, research at ALPHA through the Universities of Manchester and Liverpool, and the development of cutting edge beam instrumentation for low energy antimatter beams.
Cockcroft experts at Liverpool are also behind the Horizon 2020 “Accelerators Validating Antimatter physics” (AVA) network which received €4M from the European Union between 2016 and 2021. This was the largest-ever research and training network on low energy antimatter physics and included a Fellow based in AEgIS.
Cockcroft expert Professor Carsten P Welsch said: “We are excited to be a member of the AEgIS collaboration and the first UK University to join this experiment. We have been working with the collaboration for many years – initially on studies into new beam monitors and later within the framework of the pan-European AVA project. The experiment offers excellent prospects for ground-breaking research and we look forward to being part of this international team.”
Antimatter research at CERN’s Antimatter Factory is funded through the Engineering and Physical Sciences Research Council. UK access to CERN is made possible through its subscription, delivered and managed by the Science and Technology Facilities Council (STFC).
In addition, research into low energy antimatter facility design and optimisation, including the development of novel sensors and instrumentation, is supported by STFC through its funding of the Cockcroft Institute.
For further information on AEgIS, please visit: https://aegis.web.cern.ch/