Related papers: The D^0 -> K^0 \bar{K^0} decay beyond factorizatio…
We point out that the decay mode D^0 -> K^0 \bar{K^0} has no factorizable contribution. In the chiral perturbation language, treating D^0 as heavy, the O(p) contribution is zero. We calculate the nonfactorizable chiral loop contributions of…
It is pointed out that decays of the type $B \to D \bar{D}$ have no factorizable contributions, unless at least one of the charmed mesons in the final state is a vector meson. The dominant contributions to the decay amplitudes arise from…
We point out that the amplitudes for the decays $\bar{B}^0 \to D_s^+ D_s^-$ and $\bar{B}^0_s \to D^+ D^-$ have no factorizable contributions. If one or two of the $D$-mesons in the final state are vectors (i.e $D^*$ 's) there are relatively…
The decay modes of the type $B \to \pi \, D $ are dynamically different. For the case $\bar{B_{d}^0} \to \pi^- D^{+} $ there is a substantial factorized contribution which dominates. In contrast, the decay mode $\bar{B_{d}^0} \to \pi^0…
We point out that the decay modes B^0 --> D_s^+ D_s^- and B_s^0 --> D^+ D^- have no factorized contribution. At quark level these dacays can only proceed through the annihilation mechanism, which in the factorized limit give zero amplitude…
The decay amplitudes for anti-B0 -> Ds+ Ds- and anti-Bs0 -> D+ D- have no factorizable contributions. We suggest that dominant contributions to the decay amplitudes arise from two chiral loop contributions and one soft gluon emission…
The amplitudes for decays of the type $B_{d,s} \to D_{s,d} D_{s,d}$, have no factorizable contributions, while $B_{d,s} \to D_{s,d} D^*_{s,d}$, and $B_{d,s} \to D^*_{s,d} D^*_{s,d}$ have relatively small factorizable contributions through…
Non-factorizable effects on the color-suppressed $B\to D^{(*)}\pi$ decay modes are analyzed. Recent observations of $\Bbar^0\to D^{(*)0}\pi^0$ by Belle and CLEO strongly suggest that there exists a non-zero strong phase difference between…
While the factorization assumption works well for many two-body nonleptonic $B$ meson decay modes, the recent measurement of $\bar B\to D^{(*)0}M^0$ with $M=\pi$, $\rho$ and $\omega$ shows large deviation from this assumption. We analyze…
The various decay modes of the type $B \to \gamma D^* $ are dynamically different. In general there are factorizable contributions, and there are pole diagrams and pseudoscalar exchange contributions at meson level. The purpose of this…
A study of hadron pair production mechanism is motivated by the recent observed decays $\bar B^0\to D^{(*)+}K^-K^0$. One novel phenomenon is threshold enhancement of the kaon pair production. We show that these decays in the heavy quark…
For the color-suppressed $\bar{B}^0\longrightarrow D^{0}\pi^{0}$ decay, nonfactorizable contributions are expected to be leading and naive factorization description breaks down. We estimate $1/m_b$ power-suppressed nonfactorizable effect in…
We analyze the decay $D_s\to \phi \pi$ with QCD factorization in the heavy quark limit. The nonfactorizable contributions, including hard spectator contribution are discussed and numerical results are presented. Our predictions on the…
We investigate nonfactorizable contributions to charm meson decays in $ D \rightarrow \bar K \pi $/ $ \bar K \rho$ /$ \bar K ^{*} \pi$ / $ \bar K a_{1}$ / $ \bar K ^{*} \rho $ modes. Obtaining the contributions from spectator-quark diagrams…
We study a new $K\rightarrow\pi\pi$ decay channel with gluons in intermediate state which is normally neglected within the factorization framework. Both short-distance and long-distance parts of the amplitude are calculated. The chiral…
The decay modes of the type $B \rightarrow \pi \, \pi $ are dynamically different. For the case $\bar{B_{d}^0} \rightarrow \, \pi^+ \pi^- $ there is a substantial factorized contribution which dominates. In contrast, the decay mode…
We analyze the $B\to (J/\psi, \chi_{c0},\chi_{c1},\eta_c)K^{(*)}$ decays, which have small or even vanishing branching ratios in naive factorization assumption (FA). We calculate nonfactorizable corrections to FA in the perturbative QCD…
We consider the color suppressed (nonfactorizable) amplitude for the decay mode $\bar{B_{d}^0} \rightarrow \pi^0 \pi^{0} $. We treat the $b$-quark in the heavy quark limit and the energetic light ($u,d,s$) quarks within a variant of Large…
Two body decays of charm mesons are studied by describing their amplitude in terms of a sum of factorizable and non-factorizable ones. The former is estimated by using a naive factorization while the latter is calculated by using a hard…
In the heavy quark limit, both vector mesons in the charmless B -> VV decay should have zero helicity and the corresponding amplitude is proportional to the form factor difference $(A_1-A_2)$. The first observed charmless $B\to VV$ mode,…