On the interplay of direct and indirect CP violation in the charm sector

TL;DR

This paper analyzes how direct and indirect CP violation contribute to charm meson decay observables, emphasizing the importance of considering both effects in interpreting recent experimental evidence from LHCb.

Contribution

It provides a detailed examination of direct and indirect CP violation effects on charm decay observables, including previously neglected terms relevant for future precision measurements.

Findings

Direct CP violation could significantly impact decay asymmetries.

Neglected terms are identified as important for high-precision future studies.

The analysis clarifies the interplay between different CP violation sources in charm decays.

Abstract

Charm mixing and CP violation observables are examined in the light of the recently reported evidence from LHCb for CP violation in the charm sector. If the result is confirmed as being due to direct CP violation at the 1% level, its effect will need to be taken into account in the interpretation of CP violation observables. The contributions of direct and indirect CP violation to the decay rate asymmetry difference DeltaACP and the ratios of effective lifetimes AGamma and yCP are considered here. Terms relevant to the interpretation of future high precision measurements which have been neglected in previous literature are identified.