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So I was wondering, with all this Higgs talk going on, they just detected a particle with a mass of 125 GeV (CMS) or 126.5 GeV (ATLAS). But they still don't know what it is, since there is tons of data to go through.

How do you determine spin of a particle from such experiments? Measuring the magnetic moments of a particle or?

If they find out that it has spin 0, and the other decay channels are in agreement with this, then they can say: it's Higgs, right?

So how do you do it? What do you need to analyse?

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up vote 10 down vote accepted

For elementary particles one uses the angular distributions of the decay products in the center of mass and the spin properties of the decay products themselves.

In this particular case, because the resonance decays into two photons it has to be either spin 0 or spin 2. The angular distribution of the photons is distinctly different in the two cases.

There is a talk on this at the CERN site, so the next announcements will probably be about the spin.

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Great! Thanks ^^ – dingo_d Jul 5 '12 at 15:19

It can in principle be measured with an experiment similar to the Stern–Gerlach-experiment.

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But that is not how it is done in reality. – Siyuan Ren Jul 5 '12 at 15:25
Hello user, It could be a comment instead an answer..! – Waffle's Crazy Peanut Oct 21 '12 at 2:47

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