Related papers: |V_td/V_ts| from QCD Sum Rules on the Light-Cone
The accurate calculation of weak heavy-to-light form factors is crucial for the determination of CKM matrix elements from experimental data on B decays. In SCET, the soft-collinear effective theory, these form factors can, in the heavy…
In this paper, we calculate the $B\to D$ transition form factors (TFFs) within the light-cone sum rules (LCSR) and predict the ratio $\mathcal{R}(D)$. More accurate $D$-meson distribution amplitudes (DAs) are essential to get a more…
Form factors of the weak $\Xi_c \to \Xi(\Lambda)$ transitions are calculated within the light cone QCD sum rules. The pollutions coming from the contribution of the negative parity $\Xi_c^*$ baryon is eliminated by considering the…
We calculate the form factors and the coupling constant in the $\rho D^* D^*$ vertex in the framework of QCD sum rules. We evaluate the three point correlation functions of the vertex considering both $\rho$ and $D^*$ mesons off--shell. The…
Using the QCD {\it hybrid} (moments-Laplace) sum rule, we show $semi$-$analytically$ that, in the limit $M_b \rar \infty$, the $q^2$ and $M_b$ behaviours of the heavy-to-light exclusive ($\bar B\rar \rho~(\pi)$ semileptonic as well as the $…
$B_s \to \rho(\omega) K^{\ast}$ are useful to determine the $B_s$ distribution amplitude, as well as constrain the CKM phase angle $\alpha$. We study these decays within the Perturbative QCD (PQCD) picture. In this approach, we calculate…
Using a sample of 471 million BBbar events collected with the BaBar detector, we study the sum of seven exclusive final states B->X_s(d) gamma, where X_s(d) is a strange (non-strange) hadronic system with a mass of up to 2.0GeV/c^2. After…
We calculate the form factors and the coupling constant in the $D^{*}D \rho $ vertex in the framework of QCD sum rules. We evaluate the three point correlation functions of the vertex considering both $ D $ and $ \rho $ mesons off--shell.…
We revisited the extracting $\left|V_{ub}/V_{cb}\right|$ and $|V_{ub}|$ through calculating the ratios ${\cal B}(B^0\to D_s^{(*)+}(\pi^-,\rho^-)/ {\cal B}(B^0\to D_s^{(*)+} D^{(*)-})$ in the perturbative QCD approach, which is regarded as…
In this work we study the radiative decays of $B\to \rho (\omega)\gamma$ processes in the modified perturbative QCD approach, where the transverse momenta of the quark and gluons envolved in the interaction process are kept, and the Sudakov…
In this paper, we study the non-leptonic $B_{c}\to J/\psi V$ and $B_{c}^{*}\to\eta_{c}V$~$(V=\rho\,,K^{*})$ weak decays in the framework of QCD factorization. In the evaluation, the form factors are calculated by using the…
The weak decays of doubly heavy $\Xi_{QQ}$ baryon induced by flavor changing $b \to d$ and $ c \to u$ flavor changing neutral current within the light cone sum rules are studied. Using the parallel components of the light cone distribution…
We calculate the leading-twist O(alphas^2 beta0) corrections to the B to pi transition form factor f+(0) in light-cone sum rules. We find that, as expected, there is a cancellation between the O(alphas^2 beta0) corrections to fB f+(0) and…
Applications of QCD sum rules to exclusive decays of heavy mesons are reviewed. In detail, we discuss the calculations of the B and $D$ decay constants, the heavy-to-light form factors $f^+(p^2)$ and $f^0(p^2)$, and the strong couplings…
We present a new calculation of the B->pi form-factor f_+, relevant for the measurement of |V_{ub}| from semileptonic B->pi transitions, from QCD sum rules on the light-cone. The new element is the calculation of radiative corrections to…
QCD sum rules for vector mesons (rho, omega, phi) in nuclear matter are reexamined with an emphasis on the reliability of various sum rules. Monitoring the continuum contribution and the convergence of the operator product expansion plays a…
The two body charmless decays of $B_s$ meson to light vector mesons are analyzed within the framework of QCD factorization. This approach implies that the nonfactorizable corrections to different helicity amplitudes are not the same. The…
We study the implication of the recent measurement by the BELLE collaboration of the averaged branching fraction $\bar B_{exp} [B \to (\rho, \omega) \gamma] = (1.8^{+0.6}_{-0.5} \pm 0.1) \times 10^{-6}$ for the CKM phenomenology. Combined…
The form factors and the coupling constant of the $B_s B^* K $ and $B_s B K^*$ vertices are calculated using the QCD sum rules method. Three point correlation functions are computed considering both the heavy and light mesons off-shell in…
We propose a new method for precise determination of |V_{td} / V_{ub}| from the ratios of branching ratios BR(B -> \rho \nu \bar \nu ) / BR(B ->\rho l \nu ) and BR(B -> \pi \nu \bar \nu ) / BR(B -> \pi l \nu ). These ratios depend only on…