Shadowing in Inelastic Nucleon-Nucleon Cross Section?

Abstract

Experimental results of inclusive hard-process cross sections in heavy-ion collisions conventionally lean on a normalization computed from Glauber models where the inelastic nucleon-nucleon cross section σinelnn —a crucial input parameter—is simply taken from proton-proton measurements. In this Letter, using the computed electroweak boson production cross sections in lead-lead collisions as a benchmark, we determine σinelnn from the recent ATLAS data. We find a significantly suppressed σinelnn relative to what is usually assumed, show the consequences for the centrality dependence of the cross sections, and address the phenomenon in an eikonal minijet model with nuclear shadowing.