Scientists at the LHC announced that they have observed the decay of a particle that if anything is harder to discover that the elusive Higgs particle. The strange B meson which plays an important role to play in the Standard Model of particle physics.
The Standard Model allows particle physicists to classify subatomic particles and make predictions about particles and processes still not yet observed. The Higgs boson being the most famous example.
Mesons are one of many subatomic particle. This particle can decay into several "flavors" of which the strange B mesons being just such a particle flavor of the subatomic particle. Every sub-atomic particle will decay. Mesons 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 teams of physicists have detected the decay of strange B mesons for the first time, but the kicker is that the decay rate strange B meson was four times what the Standard Model predicted.
Discounting the amount of decay seems to support the Standard Model which is good and bad. The SM is known to be incomplete and it also can not account for Dark Matter or why the universe is made of matter instead of anti-matter.