At the Large hadron Collider saw the rare decay of the Higgs boson into two muons

The experiments CMS and ATLAS independently from each other stated that the experimental detection of the Higgs decays into two muons. Analysis of the data on proton-proton collisions with energies of 13 teraelectronvolt in the system’s center of mass showed that the probability of this decay channel within the errors coincide with the predictions of the Standard model. This is the first registered scientists, the Higgs decays into particles of the second generation, which is very important for fundamental physics. New data announced at the conference, ICHEP, ATLAS also talks about their results in the Preprint, and CMS posted the report on the website of CERN.

Since the discovery of the Higgs boson in 2012, scientists at CERN study in detail its properties and how it interacts with other elementary particles. According to the Standard model — one of the most accurate and by far the most widespread theory in particle physics — the Higgs boson has an incredibly short lifetime of the order of 10-22 seconds, and immediately after his birth should break up. Channels of its decay and their probabilities are strictly predicted by the theory, and any deviation from these predictions can be interpreted as a sign of New physics beyond the Standard model. So one of the main tasks of the CMS and ATLAS experiments after the discovery of the famous boson was the accumulation of data on rare decays.

One of the main decay channels of the Higgs boson is the decay into fermions — particles with half-integer spin. The greater the mass of the fermion, the more likely the registration of the decay of the Higgs boson with his participation. Already discovered the decays of this particle in b-quark and b-antiquark and two Tau-lepton. These particles — some of the worst representatives of their class, and belong to the third generation particles in the Standard model. But now the most important task for physicists is the search for decays of the Higgs into lighter particles of first and second generation, the probability of which is significantly below the regularly observed processes.

It to the second generation of elementary particles are muons, for which the Higgs boson is split up in a fresh experimental data CERN. Only this channel is about 1 in 5,000 of all possible decays of the Higgs boson, making it the most rare of the now was the decay of this particle. According to new data, and ATLAS and CMS within the error got into the Standard model’s prediction probability was decay. Nevertheless, the results of the two experiments there are differences in the achieved statistical precision of the evidence for the existence of the Higgs decays into two muons: CMS reached 3 σ, and ATLAS — only 2 σ. This means that in the case of CMS resulting data can be statistical fluctuation in one case out of 700, while the ATLAS can talk about the error in one case out of 40.

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