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arXiv · 1308.0878

Measuring Antimatter Gravity with Muonium

Daniel M. Kaplan·Derrick Mancini·Thomas J. Phillips·Thomas J. Roberts·Jeffrey Terry·Richard Gustafson·Klaus Kirch
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Abstract

We consider a measurement of the gravitational acceleration of antimatter, gbar, using muonium. A monoenergetic, low-velocity, horizontal muonium beam will be formed from a surface-muon beam using a novel technique and directed at an atom interferometer. The measurement requires a precision three-grating interferometer: the first grating pair creates an interference pattern which is analyzed by scanning the third grating vertically using piezo actuators. State-of-the-art nanofabrication can produce the needed membrane grating structure in silicon nitride or ultrananoscrystalline diamond. With 100 nm grating pitch, a 10% measurement of gbar can be made using some months of surface-muon beam time. This will be the first gravitational measurement of leptonic matter, of 2nd-generation matter and, possibly, the first measurement of the gravitational acceleration of antimatter.

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Daniel M. Kaplan, Derrick Mancini, Thomas J. Phillips, Thomas J. Roberts, Jeffrey Terry, Richard Gustafson, Klaus Kirch. 2013-08-12. Measuring Antimatter Gravity with Muonium. https://arxiv.org/abs/1308.0878

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