Updated results about the Higgs are being reported at Moriond today, slides available here. The organizers have given the talks titles with “BEH Boson” replacing the usual “Higgs Boson” (to promote Englert’s shot at a Nobel), but the speakers have mostly ignored this, titling their slides with the usual “Higgs” or maybe “Standard Model Scalar”. Some more details are starting to appear at the CMS site here, presumably ATLAS will soon update their site here.
The only surprise so far is that the CMS results for the gamma-gamma channel are not ready yet. Philip Gibbs has very good coverage of the latest news here, including this about CMS:
Rumour puts the CMS diphoton excess at 1.0 +- 0.2, to be shown at Moriond QCD next week perhaps.
As mentioned here a couple weeks ago, the size of the ATLAS excess in that channel has gone down since last year, now at 1.65 +/- 0.24(stat) +/- 0.21(syst) (where 1.0 is the SM prediction). If you believe Philip’s rumor, the combined ATLAS + CMS result for the gamma-gamma channel would be 1.32, consistent with the SM prediction at the level of 1-2 sigma.
In the ZZ channel, CMS reports a cross-section relative to SM of .91 +/- 0.27, ATLAS 1.7 +/- 0.5. Combining them gives 1.30, again quite consistent with the SM. For the WW channel, CMS has .76 +/- 0.21, ATLAS 1.5 +/- .6, averaging out to 1.13, again very much consistent with the SM. For channels with bottom quarks, CMS has 1.3 +/- .6 and for channels with taus CMS has 1.1 +/-.4, ATLAS says the expected signal is still to small in these channels for them to say much.
Some more talks this afternoon may give a bit more detail.
All in all, the story is that this is looking very much like a garden variety SM Higgs, which is discouraging for hopes of hints about how to get beyond the Standard Model. The experiments will continue working on improving their analyses of this data, but it seems unlikely that the picture will change much. There’s going to be a long drought now until we see significantly better data for these numbers. Probably not until 2016 until the LHC has been operating long enough to produce significant luminosity at higher energy.
The New York Times yesterday put out a wonderful special issue of its Science Times section, devoted to an excellent long article by Dennis Overbye telling the story of the Higgs discovery from the point of view of the ATLAS and CMS scientists (and emphasizing their rivalry). Highly recommended reading. The article does credit a certain blog with being the venue where a mistaken early Higgs claim was leaked (I’m sorry to hear that that ruined some people’s vacations), although the fact the the actual Higgs discovery news broke somewhere else than in the Times doesn’t get mentioned…
Professor Matt Strassler has a posting about the Times article, explaining how it shows that other particle physics bloggers were wrong to think that the 3 sigma signals reported by ATLAS and CMS back in late 2011 were strong evidence that the Higgs had been found, and that he had been right to be skeptical.
Update: New ATLAS results are here. Do not miss the extremely cool animated gifs of the evolution of the Higgs signal as data accumulated.
Update: Valuable commentary at Resonaances.
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