Constraints upon the CKM angle ϕ2 from Belle and BaBar

The Belle and BaBar experiments have measured branching fractions and CP asymmetries in the charmless decay modes B0→π+π−, B0→ρ±π∓, and B0→ρ+ρ−. From these measurements, contraints upon the CKM angle ϕ2 can be obtained. These constraints consistently indicate that ϕ2 is around 100°.