August 2, 2012 report
CERN teams post Higgs Boson papers - one ups its sigma level of certainty
The sigma levels are indicators physicists use to gauge how sure they are of their results. 5.0, for example indicates the researchers believe there is a five in ten million chance that the signals theyve seen are due to something other than what they believe it to be; in this case, evidence of a Higgs boson. 5.9 would bump up the likelihood to two in a billion.
Its important to note that both teams are still calling what theyve found to be something Higgs like rather than boasting of the discovery of the actual boson. This is because neither team has actually seen the boson, instead, they rely on measurements of particles that are thought to come into existence as a Higgs decays; according to theory, its only supposed to last for the tiniest fraction of a second, too little time to actually see or record it. Its also important to note that the sigma numbers arent measurements of how certain the researchers are that what theyve found is the Higgs, instead they are numbers that represent how certain the teams are of what theyve measured. This means its possible that all their measurements and numbers are right, but whatever caused them to come about isnt an actual Higgs, but something else that is both close to a Higgs and un-described in the Standard Model. There is no statistical number to demonstrate how sure they are of that.
What this all means is that both teams, and most physicists who study such things, are pretty sure that the work at CERN has proven that the Higgs boson does indeed exist and that further study will one day allow for the removal of the Higgs-like tag. On the other hand, if it turns out that what the teams have been measuring is due to something else, well, that will mean having to edit the Standard Model, which is a description physicists have come up with to describe all of the ingredients at their most basic level, that make up everything that exists.
ATLAS preprint: arxiv.org/abs/1207.7214
CMS preprint: arxiv.org/abs/1207.7235
© 2012 Phys.org