相关论文: Modified renormalon
In the framework of renormalon consideration, a role of the anomalous dependence of gluon propagator on the scale $\mu$ is shown for a large number of quark flavours as well as in the nonabelian theory, where the parameter of the "running"…
An ansatz is proposed for the flavor dependence of the normalization constant for the first IR renormalon in heavy quark pole mass.
We study resummed perturbative contributions due to a heavy top-quark. These renormalon contributions are evaluated for fermion propagators. Results for the top-quark width are given. Estimates of non-perturbative uncertainties are made on…
The flavour dependence of the mixed quark-gluon condensate is studied through the analysis of correlators of the hybrid current $a_{\mu}=g\bar s\gamma_{\rho}\gamma_5 G_{\rho\mu}d$. The flavour symmetry breaking for this type of condensates…
We compute gluon and quark propagators in 2-colour QCD at large baryon chemical potential mu. The gluon propagator is found to be antiscreened in the superfluid, confined phase and screened in the large-mu, deconfined phase. We present the…
We present a novel analysis of the gluon gap equation, where its full nonlinear structure is duly taken into account. In particular, while in previous treatments the linearization of this homogeneous integral equation introduced an…
A new category of phenomena is predicted in which fermions of different flavours can transmute into one another, for example $e \to \mu$ or $e \to \tau$, as a consequence of the `rotating' mass matrix due to renormalization. As examples,…
A set of renormalization invariants is constructed using approximate, two-flavor, analytic solutions for RGEs. These invariants exhibit explicitly the correlation between quark flavor mixings and mass ratios in the context of the SM, DHM…
The development of a Modified Perturbation Theory for QCD, introduced in previous works, is continued. The gluon propagator is modified as consequence of a soft gluon pairs condensate in the vacuum. The modified Feynman rules for $\alpha=1$…
We compute the renormalon ambiguity of the static potential, in the limit of a large number of flavors. An extrapolation of the QED result to QCD implies that the large distance behavior of the quark potential is arbitrary in perturbation…
By using $\k$-factorization, we derive resummation formulas for the non-abelian $q\bar{q}$ contributions to both heavy flavour production by gluon fusion, and to the next-to-leading BFKL kernel. By combining this result with previous ones…
We investigate the consistency requirements of the next-to leading BFKL equation with the renormalization group, with particular emphasis on running coupling effects and NL anomalous dimensions. We show that, despite some model dependence…
Perturbative series of some quantities in quantum field theories, such as the pole mass of a quark, suffer from a kind of divergence called renormalon divergence. In this paper, the leading renormalon in the pole mass is investigated, and a…
We study the corrections due to renormalons to the heavy hadron decay width.The renormalons contribution estimated in terms of finite gluon mass based on the assumption that the gluon mass represents the short distance nonperturbative…
The generalization of the axial anomaly is considered. It is shown that bilocal axial quark operators on the light cone possess, beside the point-like anomaly, also a light-like anomaly. The consequences for the definition of anomaly-free…
We investigate a connection between a renormalon ambiguity of heavy quark mass and the gluon condensate contribution into the quark dispersion law related with a virtuality defining a displacement of the heavy quark from the perturbative…
We compute quark and gluon propagators in 2-colour QCD at large baryon chemical potential mu. The gluon propagator is found to be antiscreened at intermediate mu and screened at large mu. The quark propagator is drastically modified in the…
The impact of the resummed next-to-leading logarithmic small-$x$ contributions to the anomalous dimension $\gamma_{gg}$ is evaluated for the unpolarized parton densities and structure functions of the nucleon. These new terms diminish the…
The quark propagator in presence of an arbitrary gluon field is calculated gauge and Lorentz covariantly order by order in terms of powers of gluon field and its derivatives. The result is independent of path connecting ends of propagator…
The problem of normalisation of the modular forms in modular invariant lepton and quark flavour models is discussed. Modular invariant normalisations of the modular forms are proposed.