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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.
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Simulation of the formation of antihydrogen via magnetobound positronium
Antihydrogen formation involving magnetobound positronium is simulated by computing classical trajectories. Simulated collisions between electrons and positrons generate magnetobound positronium, which consists of electron–positron pairs that are not energetically bound but that have spatially correlated trajectories within a magnetic field. Simulations show that antihydrogen can form if such electron–positron pairs pass near antiprotons. In addition, the possibility of forming antihydrogen atomic ions or antihydrogen molecular ions via magnetobound positronium or magnetobound antihydrogen is discussed.
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- Award ID(s):
- 1803047
- PAR ID:
- 10597411
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- AIP Advances
- Volume:
- 11
- Issue:
- 9
- ISSN:
- 2158-3226
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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