The Higgs Boson: what are the odds?

[little_monkey]

From: Revealed: The Best Higgs Plots.


"Everything is excluded at 95% confidence in the mass range from 145 GeV to 460 GeV, but there are small excesses over the range from 115 GeV to 145 GeV. A good thing to notice about this plot is that the expected CLs line is below the 95% confidence limit all the way up to 500 GeV. If there were no Higgs boson in that range they would expect to have excluded it, but they haven’t."

There is a bump at 140GeV, but only with 2-sigma significance. Are physicists grasping at straws? And what are the ramifications, should the Higgs boson be ruled out at those energies?

Thoughts.

[popeyespappy]

So it looks like the 110 to 120 range may contain a Higgs candidate as previously indicated by data from the Tevatron. Isn’t that range outside of predictions made using the standard model?

Also, looks like multiple higgs particles haven’t been ruled out yet.

[little_monkey]

At Tevatron, that turned out to be false rumours.

The odds that it will be found at the LHC are rather slim. I've been brushing up on Spontaneous Symmetry Breaking. I hadn't touched that stuff for years. The whole theory can only make sense if there is a Higg boson. Now, I'm wondering what will happen if the Higgs is completely ruled out. There are a few higgless ( I know, new word to add to the lexicon) theories, but none of them satify renormalization and/or unitarity. I've got six textbooks on QFT on my desk, each one has a chapter/section on this topic, followed by several chapters based on SSB. If Higgs is out, do I get to have a refund? Bummer.

[popeyespappy]

Do you have a link for the update on the Tevatron data? I haven't seen anything about it lately.

[little_monkey]

The latest news from the Tevatron is from July 22, 2011. From what I read, there won't be any more data study, and the thing is shutting down by the end of this year. The LHC is the only remaining hope for the Higgs.

[popeyespappy]

Got it. Although I’m still trying to figure out what happened to this bump reported in the Tevatron data from earlier this year. Was it determined to be in error?



Or is it close enough to be consistant with this data?



If so does this still apply?

We have presented NLO predictions for cross sections and dijet invariant mass distributions for one lepton, missing ET and two jets at the Tevatron. We have used a variety of cuts, including those used by the CDF collaboration who have recently reported an excess in this distribution around 150 GeV. By calculating the distribution of the invariant mass of the dijets at NLO we have ruled out large NLO K-factors as a possible source of the excess within the context of the SM. At NLO the cross sections have only a moderate dependence on the renormalisation and factorisation scales of QCD, indicating that our results could be used to constrain the overall normalisation of these backgrounds.

The SM predicts a parton-level edge in the top background around 150 GeV, an edge that is softened into a broader peak by the parton shower. Detector effects, that we have not considered here, will certainly modify this feature further. In order to gain better control over the shape of this background we would advocate the use of the more inclusive cuts for which the top background is much larger and thus more easily constrained. It becomes even more significant for cuts demanding harder jets. For instance a pj T > 40 GeV cut yields a top cross section in the region of the broad peak only a factor of 2.5 lower than the W+ jets contribution. Further information on this background could be gleaned by investigating the dijet mass distribution for the case of b-tagged (or anti-tagged) jets. In particular, the dominant source of two anti-b-tagged jets is from the hadronic decay of the W. The invariant mass of two anti-b-tagged jets should therefore peak sharply around mW, with no significant peak in the 100–150 GeV region.

[little_monkey]

The data so far from Tevatron gives a 2-sigma signal. Not good enough to confirm anything. Physicists require a 5-sigma signal to confirm anything ( like tossing a coin and getting consecutively 20 heads in a row). With the eminent shutdown I have no clue what they will do with the data that has not been analysed. I can only read from that that they may have included further data and it wasn't promising, and therefore they decided to close the file on it.

[popeyespappy]

Poop. I was kind of hoping for one last hurrah for the Tevatron before they shut it down....

[downbeatplumb]

Higgs particle could be found by Christmas

http://www.bbc.co.uk/news/science-environment-14731690

[Darth]

...

*Nods head, pretending to understand, whilst slowly backing towards the door*