Physicists have finally seen how an elementary particle, first discovered at the Large Hadron Collider, decays into two pretty quarks, exotic and short-lived particles that often appear after collisions of high-energy particles. We were able to observe this elusive process only now, for the first time in six years after the discovery of the Higgs boson. Scientists from two LHC experiments, ATLAS and CMS, reported their results simultaneously at a seminar held at CERN on 28 August.
Scientists can't see the Higgs boson. They watch for the debris that remains after the Higgs boson decays into less massive particles. The Higgs boson is expected to decay into two pretty quarks most of the time. But until now, scientists have not been able to observe this process, because other mechanisms can produce lovely quarks and mimic the Higgs decay. Scientists have previously seen how the Higgs decays into other types of particles, including particles of light called photons. This process poses no problem with Higgs imitators.
The elusive decay of an elusive particle
When the Higgs boson first became known to the general public in 2012, physicists filled in the last missing piece of the Standard Model - the theory of fundamental constituents of matter. But physicists still want to know more about the inner workings of this boson.
The Standard Model makes predictions about how often the Higgs should decay into different types of particles. Pretty quarks are one of six types of quarks in the Standard Model, each with different properties, such as mass and electrical charge. While the lightest quarks make up common particles like protons and neutrons, pretty quarks are relatively heavy and rare.
Physicists want to measure the different ways the Higgs boson decays to see if they fit the predicted models. If not, it could mean a mistake in theory. However, so far all the new results confirm the Standard Model.
Ilya Khel
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