M ar 2 00 1 QCD factorization for B →

In this work, we give a detailed discussion for QCD factorization involved the complete chirally enhanced power corrections in the heavy quark limit for B decays to two light pseudoscalar mesons, and present some detailed calculations of radiative corrections at the order of αs. We point out that the infrared finiteness of the vertex corrections in the chirally enhanced power corrections requires twist-3 light-cone distribution amplitudes (LCDAs) of the light pseudoscalar symmetric. However, even in the symmetric condition, there is also logarithmic divergence from the endpoints of the twist-3 LCDAs in the hard spectator scattering. We point out that the decay amplitudes of B → PP predicted by QCD factorization are really free of the renormalization scale dependence, at least at the order of αs. At last, we briefly compare the QCD factorization with the generalized factorization and PQCD method. PACS numbers 13.25.Hw 12.38.Bx Supported in part by National Natural Science Foundation of China and State Commission of Science and Technology of China Email: [email protected], [email protected], [email protected] Mailing address 1