The QCD factorization in $B\to DKK$ decays

Abstract

A study of hadron pair production mechanism is motivated by the recent observed decays ${\bar{B}}^0\to D^{(\ast )+}{K}^{-}{K}^0$. One novel phenomenon is threshold enhancement of the kaon pair production. We show that these decays in the heavy quark mass limit can be factorized into a generalized form. The new non-perturbative quantity is the generalized distribution amplitude which describes how a quark-antiquark pair transmits into the hadron pair. A proof of factorization of ${\bar{B}}^0\to D^{(\ast )+}{K}^{-}{K}^0$ decays to all-orders is performed by using the soft-collinear effective theory. The phenomenological application is discussed in brief.

14 pages, 2 figures