Standard model light-by-light scattering in SANC: Analytic and numeric evaluation

The implementation of the Standard Model process γγ → γγ through a fermion and boson loop into the framework of SANC system and additional precomputation modules used for calculation of massive box diagrams are described. The computation of this process takes into account nonzero mass of loop particles. The covariant and helicity amplitudes for this process, some particular cases of D0 and C0 Passarino-Veltman functions, and also numerical results of corresponding SANC module evaluation are presented. Whenever possible, the results are compared with those existing in the literature.