2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/11103We present the first completely analytical computation of the full differential γ-γpair production rate from compact radiation fields, exact to 2nd order QED, and use this result to investigate the validity of previously known approximations.6 pages, LaTeX, uses epsf.sty, rotate.sty; submitted to Astronomy & AstrophysicsAstrophysicstext