Multiparton Interactions and Rescattering∗

The concept of multiple partonic interactions in hadronic events is vital for the understanding of both minimum-bias and underlying-event physics. The area is rather little studied, however, and current models offer a far from complete coverage, even of the effects we know ought to be there. In this article we address one such topic, namely that of rescattering, where an already scattered parton is allowed to take part in another subsequent scattering. A framework for rescattering is introduced for the Pythia 8 event generator and fully integrated with normal multiparton interactions and initialand final-state radiation. Using this model, the effects on event structure are studied, and distributions are shown both for minimum-bias and jet events. ∗Work supported by the Marie Curie Early Stage Training program “HEP-EST” (contract number MEST-CT-2005-019626) and in part by the Marie Curie RTN “MCnet” (contract number MRTN-CT-2006-035606) [email protected] [email protected]