LHC detects asymmetry in particle’s decay

A short-lived subatomic particle preferentially decays into matter rather than antimatter, researchers from the Large Hadron Collider report April 23 at arXiv.org. The strange B meson is only the fourth particle known to exhibit this behavior, providing physicists with a new avenue for figuring out why matter predominates over antimatter in the universe.

The results come from the LHCb detector, which analyzes the remnants of particles that exist for about a trillionth of a second before decaying. The physicists found that the strange B meson decays 27 percent more often into matter particles than their antimatter siblings, which differ only in their charge. That number matches predictions made by the standard model, the leading theory of particle physics.

Physicists hope that as LHCb detects more of these rare strange B meson decays (it found a mere 1,000 of them in a year’s worth of data), a deviation between theory and experiment will emerge. Such a result could indicate that some unknown particle is popping into existence, interacting with the strange B meson as it decays, and then disappearing back into the vacuum.