CMB TT (top left), TE (top right), EE (bottom left), and BB (bottom right) power spectra due to helical PMFs compared to the ones that are due to non-helical PMFs. Solid lines are non-helical predictions, while dashed lines are helical predictions. Blue are the scalar modes, green the vector, and red the compensated tensor modes. We consider PMFs with B_{1 Mpc} = 4.5 nG and n_B = −1.