Apr 19 – 21, 2017
Trieste - Italia
Europe/Rome timezone
Proceedings: Il Nuovo Cimento C, Vol. 41, N. 1-2, 2018 : https://www.sif.it/riviste/sif/ncc/econtents/2018/041/01-02

Search for CP violation in baryon decays at LHCb

Apr 21, 2017, 11:30 AM
Aula Magna - Edificio H3 (Trieste - Italia)

Aula Magna - Edificio H3

Trieste - Italia

Università degli Studi di Trieste Via Valerio nº 12/2 I-34127 Trieste (TS)
Oral contribution Sessione Frontiera Intensità Sessione Frontiera Intensita'


Daniele Marangotto (MI)


The phenomenon of CP violation has been observed in the K- and B-meson systems, but not yet in the decay of any baryonic particle. Decays of beauty baryons to final states consisting of hadrons with no charm quarks are predicted to have non-negligible CP asymmetries in the SM, as large as 20% for certain three-body decay modes. The LHCb experiment is collecting unprecedented statistics of beauty baryons allowing for the first time to study CP violation in these decays. A systematic study of CP violation in beauty baryon decays can test the validity of the CKM mechanism in the baryon sector, for example by comparing asymmetries with B meson decays with identical underlying quark transitions. We report on searches for CP violation in baryon decays at LHCb using Run I data. We find evidence for CP violation in Λb -> p π- π+ π- decays with a statistical significance corresponding to 3.3 standard deviations, including systematic uncertainties, which might bring to the discovery of CP violation in the baryon sector with additional statistics. An overview of recent LHCb searches for CP violation in baryon decays will be presented, and also prospects for the future.

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