Invariants for Angular Distributions in the Production of Lepton Pairs

The dependence of the angular distribution of lepton pairs in hadronic collisions on the choice of the reference frame is discussed. A geometric description of the transformations of the angular distribution coefficients is presented. The rotational invariants including all coefficients and restrictions on them are considered. The data of the E615 experiment have been processed and a verification of rotational invariants on their basis has been presented.