Study of the angular coefficients and corresponding helicity cross   sections of the W boson in hadron collisions
  We present the Standard Model prediction for the eight angular coefficients of the W boson, which completely describe its differential cross section in hadron collisions. These coefficients are ratios of the W helicity cross sections and the total unpolarized cross section. We also suggest a technique to experimentally extract the coefficients. 
John Strologas and Steven Errede