Related papers: QCD anomalies in hadronic weak decays
Recent developments in the theory of weak decays of heavy flavours are reviewed. Applications to exclusive semileptonic B decays, the semileptonic branching ratio and charm counting, beauty lifetimes, and hadronic B decays are discussed.
To evaluate the weak decays of b-hadrons, the $\Delta B=1$ weak effective Lagrangian is the foundation. Any new physics beyond the standard model (SM) would contribute to the effective Lagrangian through the loop integration at the weak…
A weak invariant associated with a master equation is characterized in such a way that its spectrum is not constant in time but its expectation value is conserved under time evolution generated by the master equation. Here, an intriguing…
Essential to QCD applications of the operator product expansion, etc., is a knowledge of those operators that mix with gauge-invariant operators. A standard theorem asserts that the renormalization matrix is triangular: Gauge-invariant…
In the calculation of non-leptonic weak decay rates, a "mismatch" arises when the QCD evolution of the relevant weak hamiltonian down to hadronic scales is performed in unquenched QCD, but the hadronic matrix elements are then computed in…
zeta-regularized traces, resp. super-traces, are defined on a classical pseudo-differential operator A by: tr^Q(A):= f.p.tr(A Q^{-z})_{|_{z=0}}, resp. str^Q(A):= f.p.str(A Q^{-z})_{|_{z=0}}, where f.p. refers to the finite part and Q is an…
Kaon decays are an important testing ground of the electroweak flavour theory. They can provide new signals of CP violation and, perhaps, a window into physics beyond the Standard Model. At the same time, they exhibit an interesting…
QCD-based analysis of nonfactorizable parts of weak nonleptonic amplitudes is reported. Nonperturbative effects due to soft gluon exchange play a key role leading to the emergence of a dynamical rule of discarding $1/N_c$ corrections.
In the presence of a non-vanishing chemical potential the eigenvalues of the Dirac operator become complex. We use a random matrix model approach to calculate analytically all correlation functions at weak and strong non-Hermiticity for…
We calculate non-singlet quark operator matrix elements of deep-inelastic scattering in the chiral limit including operators with total derivatives. This extends previous calculations with zero-momentum transfer through the operator vertex…
Phenomenological models of heavy flavour decays differ significantly in their predictions of global features of $B_c$ decays, like the $B_c$ lifetime or the relative weight of $c\ra s$ and $b\ra c$ transitions. The $1/m_Q$ expansion which…
We recover in QCD an amazingly simple relationship between the anomalous dimensions, resummed through next-to-next-to-leading-logarithmic order, in the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution equations for the first Mellin…
We consider the most general four fermion operators in QCD for two and three massless flavors and study their renormalization in the vicinity of the Fermi surface. We show that, asymptotically, the largest coupling corresponds to scalar…
The anomalous dimensions of hadronic interpolators contain dynamical information on the properties of the associated hadron states. We point out that they provide, in particular, a link by which gauge-invariant information on exotic…
The current $3.5\sigma$ discrepancy between experimental and Standard Model determinations of the anomalous magnetic moment of the muon $a_\mu=(g-2)/2$ can only be extended to the discovery $5\sigma$ regime through a reduction of both…
The leading short-distance contributions to hadronic hard-scattering cross sections in the operator product expansion are described by twist-two quark and gluon operators. The anomalous dimensions of these operators determine the splitting…
The recent results in QCD at low energies are reported. The theoretical analysis of hadronic tau-decay is performed in complex q^2-plane. The terms of perturbation theory (PT) up to alpha^3_s are accounted, the terms of operator product…
We expose a potential flaw in standard treatments of weak decay amplitudes, including that of epsilon'/epsilon. We show that (contrary to conventional wisdom) dimension-eight operators do contribute to weak amplitudes, at order G_F alpha_s…
Flavor changing neutral current $|\Delta B|=|\Delta S|=1$ processes are sensitive to possible new physics at the electroweak scale and beyond, providing detailed information about flavor, chirality and Lorentz structure. Recently the LHCb…
A brief summary of outstanding theoretical issues and recent results from the QCD factorization approach to exclusive hadronic B decays is provided.