Search for Rare b→dℓ+ℓ− Transitions at Belle

We present the results of a search for the b→dℓ⁺ℓ⁻ flavor-changing neutral-current rare decays B+,0→(η,ω,π+,0,ρ+,0)e⁺e⁻ and B+,0→(η,ω,π⁰,ρ⁺)μ⁺μ⁻ using a 711 fb⁻¹ data sample that contains 772×10⁶ BB[over ¯] events. The data were collected at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e⁺e⁻ collider. We find no evidence for signal and set upper limits on branching fractions at the 90% confidence level in the range (3.8-47)×10⁻⁸ depending on the decay channel. The obtained limits are the world's best results. This is the first search for the channels B+,0→(ω,ρ+,0)e⁺e⁻ and B+,0→(ω,ρ⁺)μ⁺μ⁻.