Fundamental tests of antimatter gravitation with antihydrogen accelerators

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One of the outstanding grand challenges in physics is to understand the fundamental differences between matter and antimatter that have left us with a universe that is largely composed of matter. The ALPHA (Antihydrogen Laser Physics Apparatus) experiment at CERN seeks to address this question by performing precise atomic physics measurements on trapped antihydrogen atoms in order to identify minute differences with equivalent measurements in hydrogen. The collaboration is building ALPHA-g, the next generation of antihydrogen traps intended to measure antimatter gravitation.The studentship aims to design and perform gravitational free-fall measurements on antihydrogen atoms in order to directly measure antimatter gravitational acceleration as a test of the weak equivalence principle. This is an interdisciplinary experimental project with underpinnings spanning plasma, atomic and particle physics. It is a studentship with the University of Manchester where the majority would be based at CERN in Geneva, Switzerland. The student will design and analyse experimental protocol and diagnostic technique for use in ALPHA-g intended to measure the gravitational acceleration g of antimatter on Earth. More specifically, the initial measurements conducted at the beginning of the studentship will need to gain higher precision throughout the course with a careful analysis and development of the ALPHA-g apparatus with associated commissioning and testing: in particular, the focus revolves around the magnet current control, trapping systems, cooling management and respective improvements.The successful realisation of this project will require both experimental efforts as well as development of diagnostic tools for measuring and controlling the probe and background magnetic fields in the experiment. Particle and field behaviour will be modelled using software such as GPT, Opera, ANSYS and COMSOL.The student will also be expected to participate in ALPHA's general experimental programme with trapped antihydrogen atoms while mastering the operation of the full experiment. The involvement will approach the student to ultra-high vacuum systems, beam and plasma manipulation techniques, diagnostic approaches, spectroscopy and laser techniques as well as their data analysis and tools. Ultimately, the student will contribute in the results of the full operation cycle of the ALPHA machine