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 (ăn′tē-hē′lē-əm, ăn′tī-)
The antimatter equivalent of helium.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
References in periodicals archive ?
A tentative claim of few antihelium events--possibly measured by the AMS-02 collaboration--might be already at hand, waiting for a firmer experimental response in the upcoming years; see, for instance, [180].
On the one hand, the unknowns stemming from galactic CR propagation affecting the predicted galactic fluxes for antideuteron and antihelium should be correlated to the galactic antiproton spectrum and boron-to-carbon ratio data.
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.
And there's urgency in the search for antihelium. Given the expense and sensitivity of the three current research programs, failure to find an antihelium would make it hard to justify another generation of bigger, better, and costlier instruments, says Robert Streitmatter, a colleague of Mitchell at NASA's Goddard Space Flight Center in Greenbelt, Md.