While I was on my way to Johns Hopkins University Monday evening, I wrote the following post, for publication today (Wednesday). Tuesday morning, CERN stole some of my thunder by putting out a press release consistent with the conclusion I drew below. Not that I mind. A quote from the press release follows this post.
The rumor mills on various blogs have been going berserk, with claims that a Higgs particle of Standard Model type (the simplest possible version of the Higgs particle) has been found by ATLAS and CMS (the two large general purpose experiments at the Large Hadron Collider.) The claims are that the Higgs signal is at a mass-energy [E=mc2] of 125 GeV; that CMS, in its search for a Higgs particle decaying to two photons, sees a small excess (that’s two or so standard deviations, or 2 σ, away from zero signal); and that ATLAS sees a larger excess (perhaps 3 σ) in their similar analysis. (You may find it useful to read my recent article about a lightweight Standard Model Higgs particle, and why searching for it through its decays to two photons is the best way to find it but takes frustratingly long — or you might like my recent guest post on Cosmic Variance about the Higgs search.)
Well, rumors are sometimes true, and this one might be, more or less.
- More precisely, it might be true that ATLAS and CMS see excesses of the claimed type and size. We’ll find out on December 13th.
- And also, it might even be true that these excesses are signs of the Standard Model Higgs particle. We will not find that out on December 13th.
Why not? There’s just not enough data yet.