Vanishing theorems for linearly obstructed divisors

We study divisors on the blow-up of Pn at points in general position that are non-special with respect to the notion of linear speciality introduced in [6]. We describe the cohomology groups of their strict transforms via the blow-up of the space along their linear base locus. We extend the result to non-effective divisors that sit in a small region outside the effective cone. As an application, we describe linear systems of divisors in Pn blown-up at points in star configuration and their strict transforms via the blow-up of the linear base locus. © 2017 Elsevier Inc. All rights reserved