Celestial amplitudes as AdS-Witten diagrams

Both celestial and momentum space amplitudes in four dimensions are beset by divergences resulting from spacetime translation sometimes scale invariance. In this paper we consider a (linearized) marginal deformation of the CFT for Yang-Mills theory which preserves 2D conformal invariance but breaks both involves chirally coupled massive scalar. The completely finite (apart usual soft collinear divergences) take canonical form. Moreover, show they can be simply rewritten terms AdS$_3$-Witten contact diagrams evaluate to well-known $D$-functions, thereby forging direct connection between flat AdS holography.