Amazing stuff!
"Yesterday, at the annual Rencontres de Moriond conference taking place in La Thuile, Italy, the LHCb collaboration at CERN reported a new milestone in our understanding of the subtle yet profound differences between matter and antimatter. In its analysis of large quantities of data produced by the Large Hadron Collider, the international team found overwhelming evidence that particles known as baryons, such as the protons and neutrons that make up atomic nuclei, are subject to a mirror-like asymmetry in nature’s fundamental laws that causes matter and antimatter to behave differently. The discovery provides new ways to address why the elementary particles that make up matter fall into the neat patterns described by the Standard Model of particle physics, and to explore why matter apparently prevailed over antimatter after the Big Bang. ...."
From the abstract:
"The Standard Model of particle physics, the theory of particles and interactions at the smallest scale, predicts that matter and antimatter interact differently due to violation of the combined symmetry of charge conjugation (C) and parity (P). Charge conjugation transforms particles into their antimatter particles, while the parity transformation inverts spatial coordinates. This prediction applies to both mesons, which consist of a quark and an antiquark, and baryons, which are composed of three quarks.
However, despite having been discovered in various meson decays, CP violation has yet to be observed in baryons, the type of matter that makes up the observable Universe.
This article reports a study of the decay of the beauty baryon Λ0b to the pK−π+π− final state and its CP-conjugated process, using data collected by the LHCb (Large Hadron Collider beauty) experiment at CERN.
The results reveal significant asymmetries between the decay rates of the Λ0b baryon and its CP-conjugated antibaryon, marking the first observation of CP violation in baryon decays, thus demonstrating the different behaviour of baryons and antibaryons.
In the Standard Model, CP violation arises from the Cabibbo-Kobayashi-Maskawa mechanism, while new forces or particles beyond the Standard Model could provide additional contributions. This discovery opens a new path to search for physics beyond the Standard Model."
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