The Large Hadron Collider Just Detected Incredibly Rare Particle Decays

By Sarah Zhang on at

Scientists at the Large Hadron Collider have just announced the detection of a rare particle decay “harder to find than the famous Higgs particle.” The strange B meson is certainly a lot less famous than the Higgs boson, but it also has an important role to play in the Standard Model of particle physics.

For the past several decades, particle physics has been governed by the Standard Model, which allows physicists to classify all subatomic particles and make predictions about particles and processes still not yet observed. Its predictions are thus far born out—the existence of the Higgs boson being the most famous example.

Mesons are another subatomic particle. The Standard Model predicts that strange B mesons, a particle flavour of the subatomic particle, should decay at a rate of four out of every billion strange B mesons ever produced, and non-strange B mesons at a rate of one in 10 billion.

Now, the CMS and LHCb teams have detected the decay of strange B mesons for the first time, confirming the Standard Model. However, the rate of decay of non-strange B meson was four times the Standard Model’s prediction.

This isn’t entirely bad news though. Physicists have long known that the Standard Model is incomplete. It doesn’t explain dark energy or dark matter or why the universe is made of matter instead of antimatter—pretty fundamental questions. Data that deviates from the Standard Model could in fact point the way forward toward a better theory.

The data behind the meson decays was gathered back in 2011 and 2012. The LHC recently rebooted after an upgrade, and its new data could determine the fate of the Standard Model.

[Nature: Article, News and Views]

Top image: CERN