An experimental test of the weak equivalence principle for antihydrogen at the future FLAIR facility

Abstract

We present new experimental ideas to investigate the gravitational interaction of antihydrogen. The experiment can first be performed in an off-line mirror measurement on hydrogen atoms, as a testing ground for our methods, before the implementation with antihydrogen atoms. A beam of hydrogen atoms is formed by launching a cold beam of protons through a cloud of trapped electrons in a nested Penning trap arrangement. In the next step, the atoms are stopped in a series of pulsed electromagnetic coils — so-called atomic coilgun. The stopped atoms are confined in a magnetic quadrupole trap and cooled by single-photon laser cooling. We intend to employ the method of Raman interferometry to study the gravitational interaction of atomic hydrogen — and later on antihydrogen at the FLAIR facility — with high sensitivity.