ANGULAR MOMENTUM DECOMPOSITION OF CHIRAL MULTIPLETS IN FRONT FORM

In this paper, we derive the unitary transformation that relates the [Formula: see text] chiral basis {R;IJPC} to the {I;2S+1LJ}-basis in a front-form framework. From the most general expression for the Clebsch–Gordan coefficients of the Poincaré group one can see that the chiral limit brings the angular momentum coupling into a simple form that permits the relation in terms of SU(2) Clebsch–Gordan coefficients. We demonstrate that such a transformation is identical to the one obtained for canonical spin in the instant form.