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 (ăn′tē-hē′lē-əm, ăn′tī-)
The antimatter equivalent of helium.
References in periodicals archive ?
Ting hopes to find complex antimatter--perhaps antihelium (two antiprotons and two antineutrons) or antideuterons--that was forged just after the Big Bang.
There is no way that this complicated structure could be created by a high-energy collision [on Earth], If even a single nucleus of antihelium were discovered it would strongly suggest the existence of antistars.
Notwithstanding Paul Davies' review article, a few particles of antihelium were created, if fleetingly, at the Brookhaven National Laboratory in New York in 2011.
One is how often one might expect to find antihelium - or any other kind of antimatter - in the universe.
A star made of anti-matter, which would be converting antihydrogen into antihelium, would emit antineutrinos and could therefore be told from a star burning normal matter.
The goal of BESS (Balloon-borne Experiment with a Superconducting Solenoidal magnet) was the elusive antihelium nucleus.
Physicists agree that finding even one stray antihelium would be compelling evidence of antimatter galaxies.