Tag Archives: Collider

Higgs Boson Still Not Found: Huge Official Announcement from LHC, CERN


This is the joint announcement made by the ATLAS and CMS teams, LHC, CERN at the Lepton-Photon Conference, 2011 being held at Tata Institute of Fundamental Research (TIFR), Mumbai, India. This is likely to be a disappointment for many around the world, both within and without the particle physics community. The search is however on!

A warmup countdown post to this Lepton Photon Conference, 2011 is here. Semi-technical post showing all relevant results and figures can be found here.

The Higgs Boson

The Higgs Boson, predicted from considerations of symmetry in Quantum Field Theory by Peter Higgs, is the particle theoretically responsible for endowing every other massive particle with mass. It’s a boson with spin zero, with positive parity and charge.

Weak Signals

There were a number of weak signals noticed that preceded the event. These Higgs signatures’ included the W-W or the Z-Z decay channel for the Higgs as the primary decay channel. This means that the Higgs once produced will decay into two W or Z-bosons, which will in turn break up into electron-positron pairs or muon-antimuon pairs. Unfortunately, none of these events could stand up to the rigors of analysis and survive till the 5 sigma confidence level was reached in both ATLAS and CMS detectors, as yet.

No such significant excess has been observed in the lower mass gamma-gamma channel. Also, more exotic branches like the tau-tau and b-bbar (bottom-bottombar quarks) have not offered anything promising.

The results of Tevatron, Fermilab are similarly blank, with no significant excess noticed in any channel.

The Future

This is also an exciting opportunity it opens up new possible physical theories. Spontaneous symmetry breaking, at least what we know of it now, may not be the whole story. There are many rival’ theories of the Standard Model, many requiring no Higgs boson to achieve mass. These Higgless models may become the focus of mainstream research and the LHC may be next used to test the predictions of such theories.

However, it is too early to make such claims. The Higgs search is going on at full blast.

And a Promise

We will bring more articles soon, explaining what this means for the Standard Model and particle physics in general. We will also run an article elucidating the jargon of particle physics. Hold on for that it’ll come sooner that you think.


Actual results from the ATLAS and CMS joint announcement on the Higgs Boson search can be found here. All relevant facts and figures present.