Form factors for semileptonic B⁺ → K⁺ ℓℓ¯ decay in light-cone quark model

The study of semileptonic decay processes of heavy-quark mesons not only describe the internal structure of hadrons such as the hadron wave function and the hadron transverse momentum distribution, but also provides us an ideal field to study the mixing between different generations of quarks by extracting the most accurate values of Cabibbo-Kobayashi-Maskawa (CKM) matrix elements. CKM matrix elements can help us to test the Charge-Parity (CP) violation in the Standard Model (SM) and to search for new physics beyond the SM. The great virtue of semileptonic decay processes is that the effects of the strong interaction can be separated from the effects of the weak interaction into a set of Lorentz-invariant form factors, i.e, the essential information of the strongly interacting quark/gluon structure inside hadrons