Related papers: Operator Product Expansion, Renormalization Group …
In this work, we perform a detailed study of the $\tau^-\to\pi^-\pi^0\gamma\nu$ decay process within the resonance chiral theory. We pay special attention to the triple-product asymmetry in the $\tau^-\to\pi^-\pi^0\gamma\nu$ process. The…
We consider the flavour-changing operators associated with the strong axial and trace anomalies. Their short-distance generation through penguin-like diagrams is obtained within the QCD external field formalism. Standard-model operator…
We study transition form factors for radiative and rare semi-leptonic B-meson decays into light pseudoscalar or vector mesons, combining theoretical constraints and phenomenological information from Lattice QCD, light-cone sum rules, and…
We perform a detailed theoretical study of the rare radiative decay of the $W$ boson into a $B_c$ meson and an on-shell photon. The decay amplitude is described by two independent form factors, which are calculated up to the…
We summarize both the study of CP violation with $K$ and $B$ mesons, as well as rare decays of kaons, emphasizing recent developments. The topics discussed include the unitarity triangle, $\epsilon'/\epsilon$, $K\to\pi\nu\bar\nu$ and other…
We develop a systematic framework for exclusive rare B decays of the type B -> K(*)l+l- at large dilepton invariant mass q^2. It is based on an operator product expansion (OPE) for the required matrix elements of the nonleptonic weak…
The next-to-next-to-leading order perturbative QCD corrections to R_tau and the higher moments of the invariant mass distribution in the hadronic tau decays are considered. The renormalization scheme dependence of these corrections is…
We analyze the B->KK decays with the soft-gluon corrections by using the QCD light-cone sum rules (LCSR). Although QCD factorization approach calculates the leading order factorization parts and the radiative corrections from hard- gluon…
Theoretical predictions for B decay rates are rewritten in terms of the Upsilon meson mass instead of the b quark mass, using a modified perturbation expansion. The theoretical consistency is shown both at low and high orders. This method…
A new class of enhanced non-perturbative corrections to the inclusive B->X_s+gamma decay rate is identified, which contribute first at order Lambda/m_b in the heavy-quark expansion and cannot be described using a local operator product…
We give a joint description of weak radiative (WR) and nonleptonic (NL) hyperon decays (HD) in broken SU(3). The two groups of decays are linked via $SU(2)_W$ spin symmetry and vector meson dominance (VMD). We use experimental information…
The flavor-changing electromagnetic dipole operator O_7 gives the dominant contribution to the B -> Xs gamma decay rate. We calculate two-loop QCD corrections to its matrix element together with the corresponding bremsstrahlung…
We evaluate the rare radiative kaon decays K_{L,S} -> 3 gamma. Applying the requirements of gauge invariance and Bose symmetry, we derive a general form of the decay amplitude, including both parity-conserving and parity-violating…
These lectures describe CP violation and rare decays of K and B mesons and consist of ten chapters: i) Grand view of the field including CKM matrix and the unitarity triangle, ii) General aspects of the theoretical framework, iii)…
We study the renormalization group evolution (RGE) of new physics contributions to (semi)leptonic charged-current meson decays, focusing on operators involving a chirality flip at the quark level. We calculate their evolution under…
A method is described which, under the assumption of SU(3) symmetry, allows one to determine the angle gamma=Arg(Vub^*) of the unitarity triangle from time-independent measurements of the branching ratios for the decays B^+ -> pi^0 K^+ and…
We discuss the renormalon-based approach to power corrections in non-singlet deep inelastic scattering structure functions and compare it with the general operator product expansion. The renormalon technique and its variations relate the…
We compute next-to-next-to-leading order QCD corrections to the partonic processes $b\to c \bar{u} d$ and $b\to c \bar{c} s$, which constitute the dominant decay channels in standard model predictions for $B$-meson lifetimes within the…
It has been recently proposed to use the operator product expansion to evaluate the expectation values of renormalized operators without the need of a direct computation of the relevant renormalization constants. We test the viability of…
Rare kaon decays via Flavor Changing Neutral Currents are discussed in the context of the CKM unitarity triangle with a particular interest in the rare kaon decays K^+ --> pi^+ nu nubar and K^0_L --> pi^0 nu nubar. New results and the…