Charm decays

2020/02/16 by Ulrich Nierste, Nierste, Ulrich
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #Quantum and Classical Electrodynamics

paper · pdf · doi:10.48550/arxiv.2002.06686

openalex publication_date 2020/02/16 · openalex created_date 2024/04/11 · openalex updated_date 2026/07/28

Abstract

I discuss hadronic decays of D mesons with emphasis on the recent discovery of charm CP violation in D⁰→ K⁺K^-,π⁺π^- decays. The measured difference Δa_CP ≡ a_CP^dir(D⁰→ K⁺K^-) - a_CP^dir(D⁰→π⁺π^-) = (-15.4± 2.9)⋅ 10^-4 of two direct CP asymmetries exceeds the SM prediction by a factor of 7. A possible explanation is an enhancement of the penguin amplitude entering a_CP^dir by QCD effects which are not understood yet. Alternatively, Δa_CP could be dominated by contributions from new physics. In order to distinguish these two hypotheses further CP asymmetries should be measured. To this end CP asymmetries resulting from the interference of two tree-level amplitudes auch as a_CP^dir(D⁰→ K_SK_S) or a_CP^dir(D⁰ → K^*0 K_S) are especially interesting.

Related

• CP asymmetries in D→ PP^′ decays
• QCD-based estimate of direct CP asymmetry in charm decays
• Direct CP Violation in D Decays in view of LHCb and CDF Results
• Direct CP violation in charmed meson decays within the standard model
• CDF results on CP violation in charm