Related papers: Operator Product Expansion for Exclusive Decays: B…
We calculate final-state interaction corrections to the energy-angular distribution of l^+ in semi-leptonic top quark decay, where the parent top quark is produced via e^+e^- -> t\bar{t} near threshold. These are the corrections due to…
We compute the Darwin operator contribution ($1/m_b^3$ correction) to the width of the inclusive non-leptonic decay of a $B$ meson ($B^+$, $B_d$ or $B_s$), stemming from the quark flavour-changing transition $b \to q_1 \bar q_2 q_3$, where…
We show that final state interactions are important in shaping Dalitz plots for the decay $D^+ \rar K^- \p^+ \p^+$. The theoretical treatment of this reaction requires a blend of several weak and hadronic processes and hence it is…
Determining for the first time the Darwin operator contribution for the non-leptonic charm-quark decays and using new non-perturbative results for the matrix elements of $\Delta C=0$ four-quark operators, including eye-contractions, we…
The operator product expansion of current correlators at short distances, and the notion of QCD-hadron duality are the cornerstone of QCD sum rules. The extension of this programme to $T \neq 0$ is discussed, together with applications to…
Lattice studies of the doubly-charm tetraquark $T_{cc}=cc\bar u\bar d$ require the determination of the $DD^*$ scattering amplitude, which most often incorporate only meson-meson interpolators. We additionally incorporate…
We present a method of solving master equations which may describe, in their most general form, phase sensitive processes such as decay and amplification. We make use of the superoperator technique.
We study the sensitivity reach to probe the electroweak dipole operators associated with a top quark at a multi-TeV lepton collider. Studying the electroweak dipole operators is strongly motivated by precision physics. The operators exhibit…
We consider decay of metastable states of forced vibrations of a quantum oscillator close to bifurcation points, where dissipation becomes effectively strong. We show that decay occurs via quantum activation over an effective barrier. The…
The non-factorizable terms in the operator product expansion have been recognized as one of theoretical obstacles for precision determination of the mixing parameter $V_{ub}$ from semileptonic B decays. It is pointed out here that the…
Operator product expansions (OPEs) in quantum field theory (QFT) provide an asymptotic relation between products of local fields defined at points $x_1, \dots, x_n$ and local fields at point $y$ in the limit $x_1, \dots, x_n \to y$. They…
The dressed heavy quark mass \hat{m}_Q=m_Q+\bar{{\Lambda}} with \bar{{\Lambda}} being the binding energy is introduced to characterize the heavy hadrons containing a single heavy quark. A heavy quark expansion in terms of the inverse of the…
We present results of the first lattice QCD calculations of the weak matrix elements for the decays $B_c^+ \to D^0 \ell^+ \nu_{\ell}$, $B_c^+ \to D_s^+ \ell^+ \ell^-$ and $B_c^+ \to D_s^+ \nu \overline{\nu}$. Form factors across the entire…
Exclusive semileptonic B decays to radially excited charmed mesons and rare radiative B decay to the orbitally excited tensor K_2^*(1430) meson are investigated in the framework of the relativistic quark model based on the quasipotential…
We calculate nonperturbative ${\cal O}(\Lambda^2_{QCD}/m^2_c)$ corrections to the dilepton invariant mass spectrum and the forward-backward charge asymmetry in $B\to X_se^+e^-$ decay using a heavy quark expansion approach. The method has…
Exponential operator decompositions are an important tool in many fields of physics, for example, in quantum control, quantum computation, or condensed matter physics. In this work, we present a method for obtaining such decompositions,…
Exclusive rare decays mediated by $b\to s\ell\ell$ transitions receive contributions from four-quark operators that cannot be naively expressed in terms of local form factors. Instead, one needs to calculate a matrix element of a bilocal…
The D1D5 CFT gives a holographic dual description of a near-extremal black hole in string theory. The interaction in this theory is given by a marginal deformation operator, which is composed of supercharges acting on a twist operator. The…
Decay amplitudes of D(D_s)->f0(980)X, X=pi, K, are compared to experimental branching ratios with the aim of singling out the poorly known D->f0(980) transition form factor in these amplitudes. Since the other elements of the amplitudes are…
We develop a general approach to the calculation of target mass and finite t=(p'-p)^2 corrections in hard processes which can be studied in the framework of the operator product expansion and involve momentum transfer from the initial to…