##\pi \rightarrow \gamma \gamma## spin,C,P

Thread starter ChrisVer
Start date Jun 12, 2015
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In summary, the spin of a particle is significant in the decay of ##\pi \rightarrow \gamma \gamma## as it determines the possible decay modes and angular distribution of the resulting decay products. Charge conjugation is conserved in this decay, while parity is not. The spin of the pion is determined through experimental measurements, and the conservation of C and violation of P in this decay is consistent with CP-symmetry. This has important implications for understanding fundamental interactions and symmetries in particle physics.

Jun 12, 2015

ChrisVer

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I was just wondering... Is it possible to explain the J,C,P of the [itex]\pi^0[/itex], [itex]J^{CP}=0^{+-}[/itex] just from the diphoton decay?
[itex] \pi^0 \rightarrow \gamma \gamma[/itex]

The [itex]C[/itex] is straightforward.
However are the [itex]J,P[/itex] deduced by this interaction alone?

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Jun 12, 2015

Vanadium 50

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No, because you can have any spin-even particle decay to two photons.

Related to ##\pi \rightarrow \gamma \gamma## spin,C,P

1. What is the significance of spin in the decay of ##\pi \rightarrow \gamma \gamma##?

The spin of a particle plays a crucial role in the decay process as it determines the possible decay modes and the angular distribution of the resulting decay products. In the case of ##\pi \rightarrow \gamma \gamma##, the spin of the pion is 0, which means the resulting photons must have opposite spin states to conserve angular momentum.

2. How does charge conjugation (C) affect the decay of ##\pi \rightarrow \gamma \gamma##?

Charge conjugation is a symmetry operation that exchanges particles with their corresponding antiparticles. In the decay of ##\pi \rightarrow \gamma \gamma##, C-symmetry is conserved as the pion and the photons are their own antiparticles.

3. Does parity (P) play a role in the decay of ##\pi \rightarrow \gamma \gamma##?

Parity is a symmetry operation that reverses the spatial coordinates of a system. In the decay of ##\pi \rightarrow \gamma \gamma##, P-symmetry is not conserved as the initial pion has a positive parity while the final state of two photons has a negative parity.

4. How is the spin of the pion determined in the decay ##\pi \rightarrow \gamma \gamma##?

The spin of the pion is determined through experimental measurements of the angular distribution of the decay products. In the case of ##\pi \rightarrow \gamma \gamma##, the observed angular distribution is consistent with a spin-0 particle.

5. What are the implications of C and P symmetries on the decay ##\pi \rightarrow \gamma \gamma##?

The conservation of C and violation of P in the decay of ##\pi \rightarrow \gamma \gamma## is consistent with the CP-symmetry, which states that the combined operation of charge conjugation and parity must be conserved in a system. This has important implications for understanding the fundamental interactions and symmetries in particle physics.