Angular momentum decomposition of chiral multiplets in front form

摘要

In this article we derive the unitary transformation that relates the $q\barq$ chiral basis $\{R; I J^{PC} \}$ to the $\{I; ^{2S+1}L_J\}$-basis in afront-form framework. From the most general expression for the Clebsch-Gordancoefficients of the Poincar\'e group one can see that the chiral limit bringsthe angular momentum coupling into a simple form that permits the relation interms of SU(2) Clebsch-Gordan coefficients. We demonstrate that such atransformation is identical to the one was obtained for canonical spin in theinstant form.