Search for Light New Physics at 𝐵 Factories

Table 3

Results of lepton number violation searches performed by the BABAR (left column) and Belle Collaborations (right column). The limits are given at 90% confidence level.

Mode	BF UL (10^−8)	Mode	BF UL (10^−6)
𝐵^+→𝜋^−𝑒^+𝑒^+	3.0	𝐵^+→𝐷^−𝑒^+𝑒^+	2.6
𝐵^+→𝐾^−𝑒^+𝑒^+	2.3	𝐵^+→𝐷^−𝑒^+𝜇^+	1.8
𝐵^+→𝜋^−𝜇^+𝜇^+	10.7	𝐵^+→𝐷^−𝜇^+𝜇^+	1.0
𝐵^+→𝐾^−𝜇^+𝜇^+	6.7