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arXiv · hep-th/0004193

Transverse Spin in QCD: Radiative Corrections

A. Harindranath·Asmita Mukherjee·Raghunath Ratabole
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Abstract

In this paper we address various issues connected with transverse spin in light front QCD. The transverse spin operators, in $A^+ = 0$ gauge, expressed in terms of the dynamical variables are explicitly interaction dependent unlike the helicity operator which is interaction independent in the topologically trivial sector of light-front QCD. Although it cannot be separated into an orbital and a spin part, we have shown that there exists an interesting decomposition of the transverse spin operator. We discuss the physical relevance of such a decomposition. We perform a one loop renormalization of the full transverse spin operator in light-front Hamiltonian perturbation theory for a dressed quark state. We explicitly show that all the terms dependent on the center of mass momenta get canceled in the matrix element. The entire non-vanishing contribution comes from the fermion intrinsic -like part of the transverse spin operator as a result of cancellation between the gluonic intrinsic-like and the orbital-like part of the transverse spin operator. We compare and contrast the calculations of transverse spin and helicity of a dressed quark in perturbation theory.

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A. Harindranath, Asmita Mukherjee, Raghunath Ratabole. 2000-10-23. Transverse Spin in QCD: Radiative Corrections. https://doi.org/10.1103/physrevd.63.045006

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