Related papers: Modified renormalon
Constituent quark models, while successful, require a great deal of fine tuning of the short distance interactions by introducing phenomenological gluonic form factors which are ultimately designed to accurately reproduce the spectrum. We…
We investigate the flavour decomposition of the electromagnetic form factors of the nucleon, based on the chiral quark-soliton model ($\chi$QSM) with symmetry-conserving quantisation. We consider the rotational $1/N_c$ and linear…
We revisit our recently proposed formalism for dealing with the heavy quark limit of the quark Dyson-Schwinger equation. An ambiguity inherent in the original version of method is identified and resolved. Our reanalysis illustrates the…
Heavy-quark interactions in the Quark-Gluon Plasma are analyzed in terms of a selfconsistent Brueckner scheme using a thermodynamic $T$-matrix based on a potential model. The interrelations between quarkonium correlators, spectral functions…
The renormalized Dyson-Schwinger equation for the quark propagator is studied, in Landau gauge, in a novel truncation which preserves multiplicative renormalizability. The renormalization constants are formally eliminated from the integral…
We present our results on the non-perturbative evaluation of the renormalization constant for the quark field, $Z_q$, in Landau gauge within RI-MOM scheme. Using three lattice spacing we are able to isolate lattice artefacts of various…
The effective quark interaction in a relativistically covariant constituent quark model based on the Salpeter equation is supplemented by an extra phenomenological flavour dependent force in order to account for some discrepancies mainly in…
The anomalous dimension for the gauge-invariant-canonical decomposition of the energy-momentum tensor for quarks and gluons is studied by the background field method. In particular, the consistency between the background field method and…
The SU(2)_L x SU(2)_R chiral quark model consisting of the (sigma,pi) meson multiplet and the constituent quarks propagating on the homogeneous background of a temporal gauge field is solved at finite temperature and quark baryon chemical…
We investigate the flavour structure of generic extensions of the SM where quark and lepton mass hierarchies and the suppression of flavour-changing transitions originate only by the normalization constants of the fermion kinetic terms. We…
We study the structure of renormalons in the Heavy Quark Effective Theory, by expanding the heavy quark propagator in powers of $1/m_Q$. We demonstrate that the way in which renormalons appear depends on the regularisation scheme used to…
We provide a systematic renormalization group formalism to study the mass effects in the relation of the pole mass and short-distance masses such as the $\overline{\mathrm{MS}}$ mass of a heavy quark $Q$, coming from virtual loop insertions…
The smallness of fermion masses and mixing angles has recently been been attributed to approximate global $U(1)$ symmetries, one for each fermion type. The parameters associated with these symmetry breakings are estimated here directly from…
We perform an analysis of the relation between the factorization scale and the masses of the quarks in the calculation of the hard gluon coefficient in polarized deep inelastic scattering. Particular attention is paid to the role of strange…
The uncertainties from the infrared renormalons in the (color dipole) gluon distribution is estimated. It is shown that non-linear saturation effects at small-$x$ shift the first IR pole at the Borel plane from $2/\beta_2$ to $1/\beta_2$.…
Using a set of rephasing-invariant variables, it is shown that the renormalization group equations for quark mixing parameters can be written in a form that is compact, in addition to having simple properties under flavor permutation. We…
We present a new piece of evidence in favour of the importance of the quark off-shellness in the kaon. The matrix elements of the flavour-changing operators for $K_{L}\to\gamma\gamma$ comply with the general behaviour of the matrix elements…
The Lorentz-invariant gluon correlation functions, corresponding to scalar and pseudo-scalar glueballs, are calculated for Kogan's and Kovner's variational ansatz for the pure SU(N) Yang-Mills wavefunctional. One expects that only one…
We investigate the gluon, ghost and quark propagators in the Landau gauge with dynamic quarks. We perform a one-loop calculation in a model where the standard Faddeev-Popov Lagrangian is complemented by a mass term for the gluons which is…
We study $b \to s \ell_1^+ \ell_2^-$ transitions, both for the lepton flavour conserving $\ell_1=\ell_2$ and violating case $\ell_1 \neq \ell_2$, in a minimal extension of the Standard Model proposed in [1]. In this framework, the Standard…