Predicting the positive parity and zero spin of the Higgs boson?

[Intesar]

Can we predict the positive parity, and zero spin of the Higgs boson from the decay mode: 𝐻 → 𝛾𝛾?

 

[Reggid]

$H\to \gamma\gamma$ tells you that it is not spin-1, because that decay is forbidden by the Landau-Yang theorem.

I think the mere existence of that decay channel does not exclude anything else for spin and parity, without more detailed analyses of the decays.

 

[Vanadium 50]

What have you tried?

 

[Reggid]

This paper (https://arxiv.org/pdf/1506.05669.pdf) is using $H\to \gamma\gamma$ to study the spin-2 hypothesis (but they also use other channels), but it does not seem to be sensitive to the pseudo-scalar hypothesis.

 

[Intesar]

Do we expect that parity and spin are conserved in this particular decay? If so can we use the spin and parity of the two photons to predict those for the H boson?

 

[mfb]

ATLAS and CMS wrote multiple papers about that. Did you read them?

 

[Intesar]

I read(https://arxiv.org/pdf/1506.05669.pdf)
which also exist at https://dash.harvard.edu/bitstream/handle/1/23474113/4596194.pdf?sequence=1&isAllowed=y
There is also another interesting paper (https://arxiv.org/abs/1307.1432) in which the Standard Model spin-parity JP = 0+ hypothesis is compared with alternative hypotheses using the Higgs boson decays such as H→γγ. Their data provide evidence for the spin-0 nature of the Higgs boson, with positive parity being strongly preferred.

 

[Intesar]

Thank you for your clarification.