# The production of molecular positronium

@article{Cassidy2007ThePO,
title={The production of molecular positronium},
author={D. B. Cassidy and Allen P. Mills},
journal={Nature},
year={2007},
volume={449},
pages={195-197}
}
• Published 13 September 2007
• Physics, Medicine
• Nature
It has been known for many years that an electron and its antiparticle, the positron, may together form a metastable hydrogen-like atom, known as positronium or Ps (ref. 1). In 1946, Wheeler speculated that two Ps atoms may combine to form the di-positronium molecule (Ps2), with a binding energy of 0.4 eV. More recently, this molecule has been studied theoretically; however, because Ps has a short lifetime and it is difficult to obtain low-energy positrons in large numbers, Ps2 has not…

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