$CP$ violation in charm at LHCb

Abstract

$CP$While the CKM paradigm of CP violation has been tested extensively in $K$ and $B$ mesons, $CP$ violation remains unobserved in the decay of up-type quarks. The study of $CP$ violation in charm decays is thus a complementary test of the Standard Model, since it allows constraining $CP$-violating operators that might leave the observables of down-type quarks unaffected. Two recent measurements of $CP$ violation in charm decays by the LHCb Collaboration are reviewed. Their precision, below the $10^{-3}$ level, is finally entering the upper limit of the range of Standard Model predictions. The forthcoming Upgrade I of LHCb (2021–2029) will allow pushing the precision of the searches for $CP$ violation in charm below the $10^{-4}$ level.