Away-from-jet energy flow

Abstract

We consider interjet observables in hard QCD processes given by the energy flow Eout in a region away from all hard jets. Here the QCD radiation is depleted (Eout ≪ Q), and therefore these observables provide ideal means to study non-perturbative effects. We derive an evolution equation (in the large Nc limit) which resums, for large Q/E out, all leading terms arising from large angle soft emission (double logarithms are absent). We discuss the analytical features of the result and identify universal and geometry-dependent contributions. Our analysis confirms features found using numerical methods by Dasgupta and Salam. © SISSA/ISAS 2002.