Speaker
Description
The GBAR collaboration at CERN aims to directly test the Weak Equivalence Principle with a free fall of ultracold antihydrogen $\mathrm{\overline{H}}$ in Earth's gravitational field. The main principle is to first produce an antihydrogen ion $\mathrm{\overline{H}^+}$ and sympathetically cool it to $\mathrm{\mu K}$ temperature. The excess positron is then photodetached and the neutral anti-atom experiences a classical free fall. By measuring the time of flight and the annihilation position of the $\mathrm{\overline{H}}$ we determine its acceleration with a precision of $1\%$ in a first phase. I will present first evidence of $\mathrm{\overline{H}}$ production in 2022, a milestone for the experiment, as well as the status and future prospects of GBAR.
