The start of the LHC 2012 physics run is still a while off, scheduled for around the beginning of April, with beam energy likely raised a bit, to 8 TeV total in the center of mass. So, it’s going to be quite a few more months before the LHC experiments have enough new data to analyze that will allow a conclusive determination of whether the evidence seen for a Higgs around 125 GeV is confirmed, with a significance high enough to claim discovery.
The results announced on December 13 were preliminary, and more complete analyses are underway, with results to be announced relatively soon. This week’s rumor is that the full CMS Higgs to gamma-gamma analysis is showing a stronger signal than the preliminary version. The bump has moved up a bit, from 123.5 GeV to 124 GeV, and the local significance is up from 2.3 to 3 sigma, with look elsewhere effect up from .8 sigma to 2.0 sigma. This strengthens a bit the evidence for a Higgs around 125 GeV. However, the best fit size of the bump is, as with ATLAS, about twice what the SM predicts. The errors are large, so quite possibly both experiments just got a bit lucky, in which case the first few months of 2012 data may not quickly add much to the significance of the signal.
For detailed discussion of issues surrounding the Higgs analyses, see this week’s workshop in Zurich: Higgs search confronts theory.