Holonomies of gauge fields in twistor space 5: amplitudes of gluons and   massive scalars
  Scattering amplitudes of gluons coupled with a pair of massive scalars, so-called massive scalar amplitudes, provide the simplest yet physically useful examples of massive amplitudes. In this paper we construct an S-matrix functional for the massive scalar amplitudes in a recently developed holonomy formalism in supertwistor space. From the S-matrix functional we derive ultra helicity violating (UHV), as well as next-to-UHV (NUHV), massive scalar amplitudes at tree level in a form that agrees with previously known results. We also obtain recursive expressions for non-UHV tree amplitudes in general. These results will open up a new avenue to the study of phenomenology in the spinor-helicity formalism. 
Yasuhiro Abe
hep-th hep-ph