SemileptonicD-meson decays and the mechanism ofCPviolation

Semileptonic $D$-meson decays can be used to distinguish between various descriptions of $\mathrm{CP}$ violation. A nonvanishing effect would rule out the Kobayashi-Maskawa scheme. An effect below 0.4% could be explained on the basis of Higgs-boson exchange. A large effect (up to 10%) would speak in favor of left-right-symmetric theories, with a relative phase between the $V$,$A$ currents. Strong $\mathrm{CP}$ violation cannot contribute.