Related papers: Heavy-to-heavy quark decays at NNLO
In this proceedings we briefly report on the state-of-the-art NLO QCD computation for the $pp\to t\bar{t}\gamma$ process in the di-lepton channel. We describe higher-order corrections to the $e^+\nu_e \, \mu^- \bar{\nu}_\mu \,…
The inclusive decay B --> X_u l nu is of much interest because of its potential to constrain the CKM element |V_ub|. Experimental cuts required to suppress charm background restrict measurements of this decay to the shape-function region,…
A brief overview of the recent measurements of the branching ratio of the rare $K_L^0 \to \mu^+ \mu^-$ decay in the context of their agreement with the Standard Model (SM) is given. It is shown that KEK result well correlates with the SM…
We consider a different power counting in potential NRQCD by incorporating the static potential exactly in the leading order Hamiltonian. We compute the leading relativistic corrections to the inclusive electromagnetic decay ratios in this…
We study $O(\alpha_sv^2)$ corrections to decays of $^1S_0$ heavy quarkonium into light hadrons and two photons within the framework of nonrelativistic QCD, and find these $O(\alpha_sv^2)$ corrections to have significant contributions…
We present a brief (mainly bibliographical) report on recently performed calculations of terms of order O(\alpha_s^4 n_f^2) and O(\alpha_s^4 n_f^2 m_q^2) for hadronic Z and \tau decay rates. A few details about the analytical evaluation of…
Within the heavy quark expansion techniques for the heavy hadron weak decays we analytically compute the coefficient of the power suppressed dimension five chromo-magnetic operator at next-to-leading order of QCD perturbation theory with…
We report recent experimental and theoretical progress concerning the heavy-quark electro-production in the context of the ABM11 parton distribution function (PDF) fit. In the updated ABM11 analysis, including the recent combined HERA charm…
The decay B_s -> mu^+ mu^- in the Standard Model is generated by the well-known W-box and Z-penguin diagrams that give rise to an effective quark-lepton operator Q_A at low energies. We compute QCD corrections of order alpha_s^2 to its…
We investigate the interplay of chiral and heavy quark symmetries by using the NJL quark model. Heavy quarks with finite masses m(Q) as well as the limit m(Q) to infinity are studied. We found large corrections to the heavy mass scaling law…
Theoretical predictions for inclusive semileptonic B decay rates are rewritten in terms of the Upsilon(1S) meson mass instead of the b quark mass, using a modified perturbation expansion. This method gives theoretically consistent and…
Progress in the theoretical description of B-meson decays, in particular decays to light hadrons, is reviewed. The factorization properties of such decays can be analyzed using the soft-collinear effective theory. Applications of the…
In the heavy-quark limit, the hadronic matrix elements entering nonleptonic $B$-meson decays into two light mesons can be calculated from first principles including ``nonfactorizable'' strong-interaction corrections. The $B\to\pi K,\pi\pi$…
These lectures contain an elementary introduction to heavy quark symmetry and the heavy quark expansion. Applications such as the expansion of heavy meson decay constants and the treatment of inclusive and exclusive semileptonic B decays…
Quark mass effects in ${\cal O}(\alpha_s^2)$ QCD corrections to the decay rates of intermediate Higgs bosons are studied. The total hadronic rate and the partial decay rate into bottom quarks are analyzed for the Standard (scalar) Higgs…
I report on recent developments in the heavy-quark effective theory and its application to $B$ meson decays. The parameters of the effective theory, the spin-flavor symmetry limit, and the leading symmetry-breaking corrections to it are…
We present a complete $O(\alpha_s^2)$ correction to the differential width of the inclusive semileptonic decay $b\to cl\nu_l$ at the kinematical point of vanishing invariant mass of the leptons, $q^2=0$. Together with the recently computed…
We examine recent extensions of the standard model with an up-type vectorlike isosinglet T quark that mixes dominantly with the top quark. We take under scrutiny the nondecoupling effects which may reveal such a new heavy fermion through…
The full prediction of the inclusive radiative B -> Xs gamma decay rate at NNLO requires a complete evaluation of missing charm quark mass dependent matrix elements. Recent developments in the on-going computations are reported and the…
We review recent calculations of second order corrections to heavy quark decays. Techniques developed in this context are applicable to many processes involving heavy charged particles, for example the nonabelian dipole radiation.…