Yes, it is a Standard Model Higgs with spin 0.

Well, spin 2 (with positive parity) is now strongly disfavored, as a result of new results from the ATLAS and CMS experiments at the Large Hadron Collider.  CMS has disfavored it at the 98.5-99.9% confidence level (the number depending on assumptions about whether the particle is produced in collisions of gluons or in collisions of a quark and anti-quark) using their data from the particle’s decays to two lepton/anti-lepton pairs.  ATLAS has disfavored it at the 95%-99% confidence level (similarly depending on assumptions) using their data from  decays of the new particle to a lepton, anti-lepton, neutrino and anti-neutrino.  Meanwhile, there is no reason for a spin-2 particle (especially with negative parity) to have the relative decay probabilities that are observed in the data, so the fact that all these probabilities are similar to those of a simple Higgs particle disfavors spin 2 and favors spin 0.  And there’s simply no theory of a spin-2 particle (with either parity) that doesn’t have other observable particles rather nearby in mass.    No one of these arguments is definitive, but in combination they are pretty convincing.

via The Spin of the Higgs-Like Particle.

I’m a little late in getting to this, but results presented at the Moriond conference earlier in March are consistent with a spin 0 Standard Model scalar boson, or in other words, a Standard Model Higgs, and not some exotic new particle with spin 2 or other non-Higgs-like property. So, confirmation is coming in, and while we still can’t be sure if the Higgs is the simplest Standard Model Higgs predicted, the new LHC discovery is the Higgs to high probability. Break out the Nobel Prizes for the theoreticians behind this–Higgs, François Englert, and, because Nobels in the sciences are customarily limited to three names, one of Dick Hagen, Gerrry Guralnik, and Tom Kibble. Sadly, Robert Brout died in 2011 and the Nobel is not awarded posthumously, or he would most likely have been the third theoretician.

We don’t yet know if the Higgs is a simple SM Higgs, or if some surprises await, but a Higgs of some kind it is.

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