Enhanced Charm <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi>C</mml:mi><mml:mi>P</mml:mi></mml:mrow></mml:math> Asymmetries from Final State Interactions

Abstract

We show that final state interactions (FSI) within a $CPT$ invariant two-channel framework can enhance the charge-parity ($CP$) violation difference between ${D}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}$ and ${D}^{0}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{K}^{+}$ decays up to the current experimental value. This result relies upon (i) the dominant tree level diagram, (ii) the well-known experimental values for the ${D}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}$ and ${D}^{0}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{K}^{+}$ branching ratios, and (iii) the $\ensuremath{\pi}\ensuremath{\pi}\ensuremath{\rightarrow}\ensuremath{\pi}\ensuremath{\pi}$ and $\ensuremath{\pi}\ensuremath{\pi}\ensuremath{\rightarrow}KK$ scattering data to extract the strong phase difference and inelasticity. Based on well-grounded theoretical properties, we find the sign and bulk value of the $\mathrm{\ensuremath{\Delta}}{A}_{CP}$ and ${A}_{CP}({D}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{+})$ recently observed by the LHCb Collaboration.

Topics & Concepts