Neutral pions

dEdt

So apparently a neutral pion is a superposition of [itex]u\bar{u}[/itex] and [itex]d\bar{d}[/itex]. I'm having trouble understanding what this means. I have no problem understanding how the decay products of some scattering experiment could be a superposition of these two states, but how can we treat this superposition as a single particle? And how would you draw the feynman diagram for some process involving a neutral pion?

Simon Bridge

The neutral pions are decay products from scattering.
There are plenty of examples online of Feynman diagrams involving pions.

andrien

the decay of neutral pions into two photons happens through the anomaly in divergence of axial vector current.the decay has a triangle diagram.
http://prola.aps.org/abstract/PR/v177/i5/p2426_1
it is available freely here.
http://astrophysics.fic.uni.lodz.pl/...pdf/12/068.pdf