MASS DIVERGENCES OF WIDE-ANGLE SCATTERING-AMPLITUDES

The mass divergences of wide-angle scattering amplitudes are examined in a class of field theories including those with elementary vector fields. Power-counting arguments are used to show that, apart from renormalization effects, the wide-angle gauge-singlet scattering amplitude has a well-defined zero-mass limit and hence satisfies the renormalization-group equations. The same techniques also reproduce the earlier results for Yukawa and 4 theories. © 1979 The American Physical Society.