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arXiv · 2203.16174

Status and plans of the Gravitational Behaviour of Antihydrogen at Rest experiment

Philipp Blumer
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Abstract

The GBAR experiment aims to directly test the Weak Equivalence Principle of ultracold antihydrogen in Earth's gravitational field. The gravitational acceleration $\bar{g}$ will be measured to a precision of $1\,\%$ using a classical free fall of the anti-atoms from a fixed height. Reaching a precision of $10^{-6}$ is planned by performing a "quantum free fall" experiment by detecting quantum interference of $\mathrm{\bar{H}}$ due to quantum gravitational bound states above a reflecting surface. Additionally, a $\mathrm{\bar{H}}$ Lamb shift measurement is being prepared in parallel that will allow to determine the antiproton charge radius at the level of $10\,\%$.

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Philipp Blumer. 2022-03-30. Status and plans of the Gravitational Behaviour of Antihydrogen at Rest experiment. https://arxiv.org/abs/2203.16174

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