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arXiv · 1802.01438

Studying Antimatter Gravity with Muonium

MAGE Collaboration·Aldo Antognini·Daniel M. Kaplan·Klaus Kirch·Andreas Knecht·Derrick C. Mancini·James D. Phillips·Thomas J. Phillips·Robert D. Reasenberg·Thomas J. Roberts·Anna Soter
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Abstract

The gravitational acceleration of antimatter, gbar, has yet to be directly measured; an unexpected outcome of its measurement could change our understanding of gravity, the universe, and the possibility of a fifth force. Three avenues are apparent for such a measurement: antihydrogen, positronium, and muonium, the last requiring a precision atom interferometer and novel muonium beam under development. The interferometer and its few-picometer alignment and calibration systems appear feasible. With 100 nm grating pitch, measurements of gbar to 10%, 1%, or better can be envisioned. These could constitute the first gravitational measurements of leptonic matter, of 2nd-generation matter, and possibly, of antimatter.

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MAGE Collaboration, Aldo Antognini, Daniel M. Kaplan, Klaus Kirch, Andreas Knecht, Derrick C. Mancini, James D. Phillips, Thomas J. Phillips, Robert D. Reasenberg, Thomas J. Roberts, Anna Soter. 2018-02-01. Studying Antimatter Gravity with Muonium. https://doi.org/10.3390/atoms6020017

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