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arXiv · hep-ph/0109005

Frame Dependence of Spin-One Angular Conditions in Light Front Dynamics

B. L. G. Bakker·C. -R. Ji
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Abstract

We elaborate the frame dependence of the angular conditions for spin-1 form factors. An extra angular condition is found in addition to the usual angular condition relating the four helicity amplitudes. Investigating the frame-dependence of the angular conditions, we find that the extra angular condition is in general as complicated as the usual one, although it becomes very simple in the $q^+ = 0$ frame involving only two helicity amplitudes. It is confirmed that the angular conditions are identical in frames that are connected by kinematical transformations. The high $Q^2$ behaviors of the physical form factors and the limiting behaviors in special reference frames are also discussed.

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B. L. G. Bakker, C. -R. Ji. 2001-09-02. Frame Dependence of Spin-One Angular Conditions in Light Front Dynamics. https://doi.org/10.1103/physrevd.65.073002

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