Particle Physics Homework: Neutral Pion Decays

[Discostu19]

Homework Statement

Q)

1]Neutral pion decays into 2 photons which then decay into electron-positron pairs.

What would the feynman diagram look like?

2] Why is this decay of the neutral pion difficult to identify in bumble chambers?

Homework Equations

feynman diagram

The Attempt at a Solution

1]neutral pion enters feynman diagram with arrow point in, then separating into 2 photons show by squiggly lines. both of these photons then separate creatin the electron-positron annihilation shown by e- meeting the photon and e+ meeting the photon ?

2]hard to detect as photons are invisible and only show up when interacting with as particle and can have gaps between their interactions like with the electron-positron shown here

?

 

[malawi_glenn]

1. Yes, this is also called "Pion double dalitz decay"

http://www-he.scphys.kyoto-u.ac.jp/colloquium/trape/FY2008/081121_maeda.pdf

slide 13

2. WHY are the photons "invinsible" in bubble chambers? Think which particles that make tracks in bubble chambers and what property they posess.