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Abstract The standard model of particle physics currently provides our best description of fundamental particles and their interactions. The theory predicts that the different charged leptons, the electron, muon and tau, have identical electroweak interaction strengths. Previous measurements have shown that a wide range of particle decays are consistent with this principle of lepton universality. This article presents evidence for the breaking of lepton universality in beauty-quark decays, with a significance of 3.1 standard deviations, based on proton–proton collision data collected with the LHCb detector at CERN’s Large Hadron Collider. The measurements are of processes in which a beauty meson transforms into a strange meson with the emission of either an electron and a positron, or a muon and an antimuon. If confirmed by future measurements, this violation of lepton universality would imply physics beyond the standard model, such as a new fundamental interaction between quarks and leptons.
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Non-leptonic hadron decays at the LHC
This manuscript is devoted to the overview of the most recent measurements of non-leptonic hadron decays at the LHC, including results from the ATLAS, CMS, and LHCb collaborations. The non-leptonic hadron decays cover a very rich sample of the physics phenomena that form the foundation of the Standard Model of particle physics and could show effects from new particles that are not included in the Standard Model predictions. There exist multiple physics analyses of non-leptonic hadron decays, focusing on various aspects of these decays. Some of them focus on the search for rare decays that are constrained by theoretical predictions; others provide newprecise measurements of known channels. Altogether, these measurements improve existing theories and bring us deeper understanding of these processes.
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- Award ID(s):
- 2152029
- PAR ID:
- 10507186
- Publisher / Repository:
- PoS Proceedings of Science
- Date Published:
- Journal Name:
- Pos proceedings of science
- ISSN:
- 1824-8039
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Proceeding:
- https://doi.org/10.22323/1.445.0004
