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takyon [soylentnews.org] writes:

The Higgs boson reveals its affinity for the top quark [press.cern]

New results from the ATLAS and CMS experiments at the LHC reveal how strongly the Higgs boson interacts with the heaviest known elementary particle, the top quark, corroborating our understanding of the Higgs and setting constraints on new physics.

The Higgs boson interacts only with massive particles, yet it was discovered in its decay to two massless photons. Quantum mechanics allows the Higgs to fluctuate for a very short time into a top quark and a top anti-quark, which promptly annihilate each other into a photon pair. The probability of this process occurring varies with the strength of the interaction (known as coupling) between the Higgs boson and top quarks. Its measurement allows us to indirectly infer the value of the Higgs-top coupling. However, undiscovered heavy new-physics particles could likewise participate in this type of decay and alter the result. This is why the Higgs boson is seen as a portal to new physics.

A more direct manifestation of the Higgs-top coupling is the emission of a Higgs boson by a top-antitop quark pair. Results presented today, at the LHCP conference in Bologna [bo.infn.it], describe the observation of this so-called "ttH production" process. Results from the CMS collaboration, with a significance exceeding five standard deviations (considered the gold standard) for the first time, have just been published in the journal Physical Review Letters [doi.org] [open, DOI: 10.1103/PhysRevLett.120.231801]; including more data from the ongoing LHC-run, the ATLAS collaboration just submitted new results for publication [arxiv.org], with a larger significance.

Also at ZME Science [zmescience.com].

Related: Confirmed: Yes, it is the Higgs [soylentnews.org]
Successor to the LHC Could be a "Higgs Boson Factory" [soylentnews.org]

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