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Title: Sympathetic cooling of positrons to cryogenic temperatures for antihydrogen production
Abstract The positron, the antiparticle of the electron, predicted by Dirac in 1931 and discovered by Anderson in 1933, plays a key role in many scientific and everyday endeavours. Notably, the positron is a constituent of antihydrogen, the only long-lived neutral antimatter bound state that can currently be synthesized at low energy, presenting a prominent system for testing fundamental symmetries with high precision. Here, we report on the use of laser cooled Be + ions to sympathetically cool a large and dense plasma of positrons to directly measured temperatures below 7 K in a Penning trap for antihydrogen synthesis. This will likely herald a significant increase in the amount of antihydrogen available for experimentation, thus facilitating further improvements in studies of fundamental symmetries.  more » « less
Award ID(s):
1806380 1806305
Author(s) / Creator(s):
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Date Published:
Journal Name:
Nature Communications
Medium: X
Sponsoring Org:
National Science Foundation
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