Theoretical Calculation Of The Decay B⁰�'D₀^*(2400)^-l⁺v_l And B¹�'(?)(2420)⁰l⁺V_l

B physics has been one of the most hot topic area in particle physics since the 80s of last century. There are about 10¹²～10¹³ mesons will be produced at LHC every year, and a series of rare decays will be observed hopefully. The large quantity of the B meson and the abundance of the dynamical mechanism make it become a highlight in the research. But the theoretical study about the decay of B meson to P-wave meson was seldom from now on, and there is a large quantity of branching ratios in these decays. In this thesis we calculate the decay process B⁰�'D₀^*(2400)^-l⁺ν_l and B⁺�'(D|-)₀^*(2420)⁰l⁺ν_l,then, predict the production of the two P-wave mesons.Since the mass of the initial meson is much greater than that of the final meson in the decay processes. So the momentum recoil can be great. And the P-wave meson is in the orbital excited state, the relative effects is notable. Due to the Bethe-Salpeter equation is four-demensional in space-time to describe a bound state problem based on the perturbative quantum field theory and it can deal with the great momentum recoil problem well. So in this paper we apply the method of expended potential model based on the Bethe-Salpeter equation to compute the decay processes.The procedure of the calculation is that: according to solve the instantaneous Salpeter coupling equation, we get the eigenvalue fuction of the initial and the final meson in the center mass system of their own. Based on the spectator model boosting the wave function of the final meson to the CMS of the initial meson. According to the Mandelstam method, use the BS wave function to formulate the weak current matrix element, then, based upon the current-current coupling theory in the pattern of V-A, we can get the invariant transition amplitude. Then, integrate over the phase-space of the final state to formulate the analytic expressions of the decay width. Apply the computer program to do the numerical solution ,we get the conclusion of the branching ratio.At last, the numerical resluts of the branching ratio in the decay channel B⁰�'D₀^*(2400)^-l⁺ν_l and B⁺�'(D|-)₀^*(2420)⁰l⁺ν_l are 5.6×10^-3and 6.1×10^-3respectively. Compared with the related experimental data our numerical results are very approached.