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A. Bassetto

Publications and source records attributed to A. Bassetto.

38 records · Page 3Linked to original sources

Non Perturbative Solutions and Scaling Properties of Vector, Axial--Vector Electrodynamics in $1+1$ Dimensions

We study by non perturbative techniques a vector, axial--vector theory characterized by a parameter which interpolates between pure vector and chiral Schwinger models. Main results are two windows in the space of parameters which exhibit acceptable solutions. In the first window we find a free massive and a free massless bosonic excitations and interacting left--right fermions endowed with asymptotic \hbox{states}, which feel however a long range interaction. In the second window the massless bosonic excitation is a negative norm state which can be consistently expunged from the ``physical" Hilbert space; fermions are confined. An intriguing feature of our model occurs in the first window where we find that fermionic correlators scale at both short and long distances, but with different critical exponents. The infrared limit in the fermionic sector is nothing but a dynamically generated massless Thirring model.

hep-th↗

Gauge Invariance and Anomalous Dimensions of a Light-Cone Wilson Loop in Light-Like Axial Gauge

Complete two-loop calculation of a dimensionally regularized Wilson loop with light-like segments is performed in the light-like axial gauge with the Mandelstam-Leibbrandt prescription for the gluon propagator. We find an expression which {\it exactly} coincides with the one previously obtained for the same Wilson loop in covariant Feynman gauge. The renormalization of Wilson loop is performed in the $\MS-$scheme using a general procedure tailored to the light-like axial gauge. We find that the renormalized Wilson loop obeys a renormalization group equation with the same anomalous dimensions as in covariant gauges. Physical implications of our result for investigation of infrared asymptotics of perturbative QCD are pointed out.

hep-ph↗