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Meir Achuz
#6
May3-05, 07:56 PM
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There are some errors in your analysis.
1. C for two photons is just (-1)(-1)=+1. There is no (-1)^{l+s) because the photon is its own antiparticle.
2. I don't understand "Because of momentum conservation, it is L=0 and therefore l=0." Angular momentum conservation applies to J and not to L
3. Conservation of parity from a pseudoscalar \pi^0 requires L=1 for the two photon state, and then the two photons must be in total spin S=1+1=1. This spin state of the photons was verified by looking at their relative polarization. This argument, in reverse, was originally proposed by Yang in the 50's to measure the parity of the pi0. The experiment found crossed polarizations for the photons, showing they were in a spin one state.
4. The above results just depends on conservation laws, and have nothing to do with more detailed theory.