CP Violation in Neutral Kaon Decays

[JG1009]

I was recently reading an article that attempted to explain how the results of the Cronin-Fitch experiment illustrated CP violation. (http://hyperphysics.phy-astr.gsu.edu/hbase/particles/cronin.html) However, it wasn't very well explained. Could someone please explain this to me?

 

[ChrisVer]

What did confuse you?
The Kaon decay modes are explained in terms of K-short and K-long. These states are CP-eigenstates.
These can either decay to a 2 or 3 pion products. The 2,3 pion products have different CPs.
The 2 pions have CP=1 while the 3 pions systems dominantly have CP=-1.
If CP is conserved, Kshort and Klong, having different CPs, would decay only to 2 pions (the CP=1 Kshort) or to 3 pions (the CP=-1 Klong).
So if you send your beam and let the Kshort decay, after a while you only have Klongs in your beam and those will decay to 3 pions alone... the fact that you measured a significant number of 2 pion decays, is showing you that there is CP violation.