Scientists discover 4 new particles (earthsky.org)
Posted by EarthSky Voices in Human World | March 14, 2021
On March 3, scientists at CERN in Geneva – which operates the the Large Hadron Collider, largest particle physics laboratory in the world – announced the discovery of 4 brand-new elementary particles.
By Patrick Koppenburg, Dutch National Institute for Subatomic Physics and Harry Cliff, University of Cambridge
This month is a time to celebrate. On March 3, 2021, CERN announced the discovery of four brand new particles at the Large Hadron Collider (LHC) in Geneva. This means that the LHC has now found a total of 59 new particles, in addition to the Nobel prize-winning Higgs boson, since it started colliding protons – particles that make up the atomic nucleus along with neutrons – in 2009. Excitingly, while some of these new particles were expected based on our established theories, some were altogether more surprising.
The LHC’s goal is to explore the structure of matter at the shortest distances and highest energies ever probed in the lab, testing our current best theory of nature: the Standard Model of Particle Physics. And the LHC has delivered the goods: it enabled scientists to discover the Higgs boson, the last missing piece of the model. That said, the theory is still far from being fully understood.
One of its most troublesome features is its description of the strong force which holds the atomic nucleus together. The nucleus is made up of protons and neutrons, which are in turn each composed of three tiny particles called quarks (there are six different kinds of quarks: up, down, charm, strange, top and bottom). If we switched the strong force off for a second, all matter would immediately disintegrate into a soup of loose quarks, a state that existed for a fleeting instant at the beginning of the universe.
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more: https://earthsky.org/human-world/cern-lhc-4-new-particles?
Longish article, with nerdly details. As explained in the article, these are not "fundamental" particles despite the subhead above.
