What is the Higgs Bosun 2

Particle Physics: The Higgs and the Second Generation

Eight years after the discovery of the Higgs boson, physicists are still busy investigating the properties of the newcomer. In recent years, for example, they have been able to demonstrate that the "Higgs" interacts with the two most massive of the six quarks and with the very stout siblings of the electron, the so-called tau leptons. All of these particles belong to the third and heaviest "generation" in the standard model of elementary particles, the comprehensive scheme with which experts catalog the microcosm.

Now researchers on the 27-kilometer Large Hadron Collider near Geneva could for the first time have demonstrated contact between the Higgs and a member of the second generation: the famous boson also decays into muons, the teams of the detectors ATLAS and CMS report in two not yet from experts verified advance publications.

Muons belong to the same family as tau and electron, they are, in a sense, the sandwich child. They are only six percent the mass of a rope, which makes it difficult to demonstrate the interaction with the Higgs boson. This is only a stimulus in the omnipresent Higgs field, which gives elementary particles their mass and therefore interacts more strongly with heavy particles than with lightweights. Correspondingly, the Higgs particle is much more likely to disintegrate into massive particles of the third generation.

Conversions into muons, on the other hand, are much rarer: only every 5,000th of the Higgs bosons generated at the LHC decays into medium-weight particles, reports CERN. It is correspondingly difficult to collect enough of the events in order to be able to prove the subatomic process properly. So far, neither ATLAS nor CMS have exceeded the threshold of »five sigma«, above which a deceptive statistical fluctuation is as good as impossible. CMS is at least a good three sigma, which corresponds to an error probability of around 1 in 700.

Should the result condense, it would confirm the trend of most of the other measurements at the LHC: So far, the Higgs particle has behaved exactly as the Standard Model of particle physics predicts. If there are small deviations in the details, an even larger particle accelerator will probably only be able to detect them.