Measurement of matter-antimatter differences in beauty baryon decays

LHCb Collaboration

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59 Citations (Scopus)
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Differences in the behaviour of matter and antimatter have been observed in K and B meson decays, but not yet in any baryon decay. Such differences are associated with the non-invariance of fundamental interactions under the combined charge-conjugation and parity transformations, known as CP violation. Here, using data from the LHCb experiment at the Large Hadron Collider, we search for CP-violating asymmetries in the decay angle distributions of Λb 0 baryons decaying to pπ- π+ π- and pπ-K+K- final states. These four-body hadronic decays are a promising place to search for sources of CP violation both within and beyond the standard model of particle physics. We find evidence for CP violation in Λb 0 to pπ- π+ π- decays with a statistical significance corresponding to 3.3 standard deviations including systematic uncertainties. This represents the first evidence for CP violation in the baryon sector.

Original languageEnglish
Pages (from-to)391-396
Number of pages6
JournalNature Physics
Issue number4
Publication statusPublished - 3 Jan 2017

ASJC Scopus subject areas

  • Physics and Astronomy(all)


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