Tag Archives: Cern

LHC Experiments ATLAS and CMS to update their Higgs boson hunt results

CERN has announced that the two experiments leading the search for the Higgs boson, ATLAS and CMS will update their results concerning the search for the Higgs boson tomorrow on July 4th.

Last December the ATLAS and CMS experiments reported they excluded a Higgs boson in the mass range above 130 GeV and up to 500 GeV and observed a modest excess of collisions compatible with a Higgs boson at about 125 GeV, but with a low statistical significance.

The probability for the observed December 2011 excess to be the result of a statistical fluctuation (rather than a Higgs boson) is about one chance in a thousand.

With current computer technologies, physicists can easily look at thousands of distributions while trying to find a handful potential Higgs boson events among billions of proton-proton collisions. In clear: there is always a chance that a few mundane proton proton collisions will look like collisions in which a Higgs boson was produced and then decayed. It is for this reason that particle physics needs to have very strict criteria to assert whether an effect is real or is just a fluke of statistics. To assert with certitude that a certain outcome is not just the result of a statistical fluctuation we require that the probability that a fluctuation would explain the observation to be lower than one in a few millions.
Continue reading LHC Experiments ATLAS and CMS to update their Higgs boson hunt results

One big step closer to finding or excluding the Higgs boson.

Today the ATLAS and CMS experiments at CERN’s Large Hadron Collider (LHC) have presented the results of the analysis of all their most recent data. One tricky thing about the Higgs boson is that we do not know what is its mass, and so one needs to look for it in all its possible decay channels. ATLAS and CMS show that there is no Higgs boson with a mass above about 130 GeV and below 115 GeV (it could still be heavier than about 500 GeV but this is not favored by the theory).

Whether the Higgs boson exists or not, the ATLAS and CMS experiments moved today one big step closer to the answer.
Continue reading One big step closer to finding or excluding the Higgs boson.