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arXiv · nucl-th/9812030

A Poincaré Covariant Current Operator for Deep Inelastic Structure Functions and Deuteron Electromagnetic Properties

F. M. Lev·E. Pace·G. Salme`
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Abstract

In front-form dynamics the current operator can be constructed from auxiliary operators, defined in a Breit frame where initial and final three-momenta of the system are directed along the $z$ axis. Poincaré covariance constraints reduce for auxiliary operators to the ones imposed only by kinematical rotations around the $z$ axis. Elastic and transition form factors can be extracted without any ambiguity and in the elastic case the continuity equation is automatically satisfied, once Poincaré, ${\cal P}$ and ${\cal T}$ covariance, together with hermiticity, are imposed. Applications to deep inelastic structure functions in an exactly solvable model and to the calculation of the deuteron electromagnetic form factors are presented.

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F. M. Lev, E. Pace, G. Salme`. 1998-12-10. A Poincaré Covariant Current Operator for Deep Inelastic Structure Functions and Deuteron Electromagnetic Properties. https://arxiv.org/abs/nucl-th/9812030

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