17 August 2010
New insight into matter/antimatter conundrum
by Kate Melville
Physicists at the Fermilab Tevatron particle collider have observed that short-lived B meson particles produced from proton collisions break down into debris that includes slightly more matter than antimatter, just the sort of matter/antimatter asymmetry that could explain the prevalence of matter over antimatter in the universe. The results are being published this week in Physical Review Letters.
There are other processes described by current physics theory that would produce tiny excesses of matter, but the amounts the theories predict are far smaller than necessary to create the universe we observe. The new experiments suggest that we are on the verge of accounting for the quantities of matter that exist today. But the truly exciting implication is that the experiment implies that there is new physics - beyond the widely accepted Standard Model - that must be at work. And if that's the case, major new physics discoveries lie ahead.
The results emerge from a complicated and challenging analysis, and have yet to be confirmed by other experiments. If the matter/antimatter imbalance holds up under the scrutiny of researchers at the Large Hadron Collider in Europe and other groups at Fermilab, it will likely stand as one of the most significant milestones in high-energy physics, according to researcher Roy Briere, of Carnegie Mellon University. A more detailed description of the experiments and Briere's analysis of the results and their implications appear in APS Physics.
Source: American Physical Society