Measurement of the gravitational acceleration of antihydrogen

The gravitational force acting on antiparticles has never been directly measured to date. A method for measuring the gravitational effects on antihydrogen by equilibrating the gravitational force with a magnetic gradient is discussed. The systematic and statistical errors inherent to the measurement will be presented. It will be shown that a measurement of gravity at 1% can be realised using ∼ 5 × 10⁵ antihydrogen atoms. The production of antihydrogen atoms in conditions suitable for the measurement is also discussed. This revised version was published online in August 2006 with corrections to the Cover Date.