AntiHelium Observed for the First Time

One the big questions that trouble cosmologists and particle physicists is the distribution of matter and antimatter in the Universe. It certainly looks is if matter dominates the cosmos but looks can be deceiving. We may just live in a corner of the universe that happens to be dominated by matter.

Today, we find there's a little extra antimatter in our corner thanks to the work of the STAR collaboration at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory in the US.

These guys banged together 10^9 gold nuclei at energies of 200 GeV and spotted 18 antinuclei of helium-4 in the ensuing wreckage. That's an impressive achievement by an standards--at the very least we now know antihelium-4 can exist.

These kinds of impacts create a hot blob of more or less equal numbers of quarks and antiquarks, a so-called quark gluon plasma. This cools down forming various particles and their antiparticles.

no time. however, uber awesome.

Hmm. I wonder if there is AntiHeium-3, James? ;)