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Pairs in the light-front and covariance

J. P. B. C de Melo·J. H. O. Sales·T. Frederico·P. U. Sauer
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Abstract

The electromagnetic current of bound systems in the light-front is constructed in the Breit-Frame, in the limit of momentum transfer $q^+=(q^0+q^3)$ vanishing. In this limit, the pair creation term survives and it is responsible for the covariance of the current. The pair creation term is computed for the $j^+$ current of a spin one composite particle in the Breit-frame. The rotational symmetry of $j^+$ is violated if the pair term is not considered.

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J. P. B. C de Melo, J. H. O. Sales, T. Frederico, P. U. Sauer. 1998-02-14. Pairs in the light-front and covariance. https://doi.org/10.1016/s0375-9474(98)00070-0

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