Non-Gaussianity and excursion set theory: Halo bias

Abstract

We study the impact of primordial non-Gaussianity generated during inflation on the bias of halos using excursion set theory. We recapture the familiar result that the bias scales as ${k}^{\ensuremath{-}2}$ on large scales for local type non-Gaussianity but explicitly identify the approximations that go into this conclusion and the corrections to it. We solve the more complicated problem of nonspherical halos, for which the collapse threshold is scale-dependent.