Heart of Matter
Science in the National
The KOPIO Experiment
The physicists who designed KOPIO are looking for a very rare
reaction with the potential to explain the observed lack of
symmetry between matter and anti-matter in the universe.
We know that the Universe “prefers” matter
over antimatter, even though these mirror-image particles once
appeared to follow perfectly symmetrical laws of physics. If the
laws governing matter and antimatter were symmetrical, we would
not have a Universe. Why did the Big Bang produce matter instead
of an even 50/50 mixture of matter and antimatter?
The KOPIO Experimental apparatus (particle beam enters from
The answer may lie in the discovery of a new asymmetry of
nature, evidence that an antimatter universe, a mirror image of
our own, would not behave in precisely the same way. Using the
AGS proton accelerator at Brookhaven National Laboratory, the
KOPIO experimenters wish to create an intense beam of kaons to
study special very rare decays (viz. a kaon decaying into a
neutral pion, a neutrino, and an antineutrino). The discovery
and observation of these rare reactions will incisively probe
charge parity (CP) symmetry violation, fundamental evidence
that a mirror-image anti-universe would look slightly different
from our own. This is important because the laws of physics are
incomplete without the ability to explain the observed
large-scale matter/antimatter asymmetry of the universe which is
intimately related to subtleties that distinguish the behavior
of matter from that of antimatter.
Read more in "KOPIO
– A New Investigation into the Heart of Matter", a technical
discussion of the experiment.
January 24, 2006
by Gary Schroeder.