Related papers: Determination of QCD condensates from tau-decay da…
Inspired by the relation between the hadronic decay of the tau lepton and the electron-positron annihilation into hadrons, we derive new tests of perturbative QCD. We design a set of commensurate scale relations to test the self-consistency…
We present the results of a search for new particles decaying to tau pairs using the data corresponding to an integrated luminosity of 195 pb^-1 collected from March 2002 to September 2003 with the CDF detector at the Tevatron. Hypothetical…
We calculate analytically properties of holographic superconductors in the probe limit. We analyze the range $1/2 < \Delta < 3$, where $\Delta$ is the dimension of the operator that condenses. We obtain the critical temperature in terms of…
Tau decays into hadrons foresee the study of the hadronization of vector and axial-vector QCD currents, yielding relevant information on the dynamics of the resonances entering into the processes. We analyse tau -> (3 pion) nu_tau decays…
We use results of fits to the OPAL spectral data, obtained from non-strange hadronic \tau decays, to evaluate the difference between the vector and axial current correlators, \Pi_{V-A}(Q^2). The behavior of \Pi_{V-A}(Q^2) near euclidean…
The dispersive approach to QCD, which properly embodies the intrinsically nonperturbative constraints originating in the kinematic restrictions on relevant physical processes and extends the applicability range of perturbation theory…
We calculate the vector and axial-vector current correlators in the coordinate space and compare them with the experimental information obtained through the spectral functions of hadronic tau decays measured by ALEPH. Lattice data are…
The disorder parameter $<\mu>$ for the condensation of monopoles in QCD is estimated analytically in terms of gauge invariant field strength correlators. The continuum limit is discussed.
We study the phenomenology of the \tau^- \to \pi^- \nu_\tau \ell^+ \ell^- decays (\ell = e, \mu), predicting the respective branching ratios and di-lepton invariant-mass spectra. In addition to the model-independent (QED) contributions, we…
Using the recently proposed generalization to an arbitrary number of colors of the strong coupling approach to lattice gauge theories\cite{Grignani:2003uv}, we compute the chiral condensate of massless QCD in the 't Hooft limit.
We compute the matching coefficients between QCD and non-relativistic QCD for external vector, axial-vector, scalar and pseudo-scalar currents up to three-loop order. We concentrate on the non-singlet contributions and present precise…
I report on some recent work done in collaboration with Santi Peris and Boris Phily (hep-ph/0007338) where, using the Aleph data on vector and axial-vector spectral functions, we test simple duality properties of QCD in the large-Nc limit…
The spectral functions of the vector current and the axial-vector current have been measured in hadronic tau decays using the OPAL detector at LEP. Within the framework of the Operator Product Expansion a simultaneous determination of the…
We study the asymptotic short-distance behaviour as well as the asymptotic large-distance behaviour of the gauge-invariant quark-antiquark nonlocal condensates in QCD. A comparison of some analytical results with the available lattice data…
We estimate the quark condensate in one-flavor massless QCD from the known value of the gluino condensate in SUSY Yang-Mills theory using our newly proposed "orientifold" large-N expansion. The numerical result for the quark condensate…
We present an update of the measurement of alpha_s(m_tau) from ALEPH tau hadronic spectral functions. We report a study of the perturbative prediction(s) showing that the fixed-order perturbation theory manifests convergence problems not…
We perform the most attractive channel (MAC) analysis in the top mode standard model with TeV-scale extra dimensions, where the standard model gauge bosons and the third generation of quarks and leptons are put in D(=6,8,10,...) dimensions.…
We perform an analysis of the topological and chiral vacuum structure of four-dimensional QCD on the lattice at finite temperature. From correlation functions we show the existence of local correlations between the topological charge…
A set of well known chiral sum rules, expected to be valid in QCD, is confronted with experimental data on the vector and axial-vector hadronic spectral functions, obtained from tau-lepton decay by the ALEPH collaboration. The…
We derive thermal QCD sum rules for the correlation function of two vector currents in the rho-meson channel. It takes into account the leading non-perturbative corrections from the additional operators, which appear due to the breakdown of…