The Lingering Hope for Higgs Boson in 2011 Continued

Better Higgs Combo, New Unofficial Higgs Combo & Higgs Signal Plots (by Philip E. Gibbs): Abstract: It is traditional to present the results of searches such as Higgs hunting as Brazil plots that show us where a signal can be excluded at 95% confidence, but when the data starts to show a positive signal it is better to show signal plots like Higgs Signal Plot shown herein. This is just the observed confidence level limit minus the expected with the error bands for one and two sigma statistical variation shown around the signal level line. From about 135 GeV to 150 GeV it disfavors both a signal and no signal of a standard model Higgs.

It is tempting to say that this rules out standard model physics in this region but I think it is too soon to draw such a conclusion. It may be that there is a SM Higgs boson at say 140 GeV but the resolution is not sufficiently good to get a clean signal there, or more data may see the line fluctuate down to the no signal level. It is important to remember that we are still at the stage where just a few signal events have a big effect on the curve. More detail will emerge with more data. Furthermore, the plot above is only an approximation that does not properly take into account all uncertainties and correlations.

Did the Higgs Signal Fade? & the Best Higgs Plots Revealed (by Philip E. Gibbs): Abstract: The CMS excess did not fade at all, the difference was due to a change in the analysis from Cut-based to MVA-based for the dominant WW channel. The ATLAS combinations when reconstructed consistently only show a small decrease in the excesses. Not the large decrease advertised. Higgs boson hints are still alive. What is particularly interesting now is the bump at 140 GeV. Some people said that this excess came mostly from the WW channel, yet when the WW channel is removed the bump is still there with nearly 2-sigma significance. The two bumps peaking at 118 GeV and 128 GeV are also the right size for a Higgs signal but error bands are still too big. Any of these bumps could be statistical fluctuations but it is very unlikely that they all are. With current data available in the high-resolution channels it is not yet possible to draw robust conclusions, but I think I have demonstrated that this will be the best way to find the Higgs with future data. I hope the experimenters will take note and produce similar plots from the official data. Updated results with 2.5/fb could appear within weeks and we will see where the three candidate bumps are heading.