Search for the rare charm meson decays D⁰ → h h^(') l⁺ l^-

Electroweak penguin quark transitions mediated by Flavor Changing Neutral Currents c → u l l (where l is an electron or muon) are forbidden at tree level in the Standard Model (SM). They proceed through an electroweak box or loop diagram in the SM and are further suppressed due to the GIM mechanism and the small quark masses in the loop. This provides a new window for probing NP models such as leptoquarks, Z' model and minimal supersymmetric standard model. Babar has observed the decay D⁰→ K^-π⁺e⁺e^- in the mass range 0.675 < m(e⁺e^-) < 0.875 GeV where long-distance contributions dominate. LHCb has observed the decays D⁰→ h h^(') μ⁺μ^- (h = K, π) and gave the first full angular analysis of the π^-π⁺μ⁺μ^- and K^-K⁺μ⁺μ^- modes. We present our study of the decays D⁰ →h h^(') l⁺ l^-, where h = K, π  and l = e, μ using 942 fb^-1 of e⁺e^- data collected at or close to the center-of-mass energy of the Υ(4S) and Υ(5S) with the Belle detector at KEK.