Vinelli, Giuseppe — Measurement of the Gravitational Behaviour of Antimatter

The QUPLAS (QUantum interferometry with Postitrons and LASers) experiment aims to test the gravity theory by measuring the Positronium (Ps) fall in the Earth’s gravitational field. Such measurement would be a test of the Weak Equivalence Principle and the CPT symmetry and is further motivated by the lack of information on antimatter that could improve the standard model.
The setup and techniques of the experiment, which are in continuous development, involve the three phases of production, preparation, and interference of the positronium beam. To operate with an electrically controllable and focusable atom, the first phase aims to produce negative Ps- ions by impinging positrons on a Na-W target. Ps is then obtained by detaching the excess electron by laser driven photodetachment. To extend its lifetime, each atom is excited to the Rydberg state and then passes through the interferometer before the detection. The project sees me mainly involved as an experimental physicist, but I also dealt with simulating photodetachment. I will also deal with simulating the interferometer soon.