Improving event generators with effective theories

by Bauer, C. (LBL)

Thursday 19 Oct 2006, 14:00 → 15:00 Europe/Zurich

TH Auditorium (CERN)

Event generators are a crucial tool to meaningfully compare experimental data to underlying theories. Parton shower algorithms are necessary to produce the many final state partons required to build realistic final states. Since parton showers rely on splitting functions derived in the collinear limit of QCD, they are unable to properly describe large angle emissions, which are crucial to interpret events with several well separated jets. Furthermore, parton showers are derived at tree level, and adding perturbative corrections requires additional work. While individual solutions exist for the above mentioned problems, so far no tool is available that can be systematically improved to include such new effects. In this talk I will show how parton showers can be derived as the leading order result of an effective theory. I will then present how to go beyond the leading order and include large angle emissions, higher orders in perturbation theory and subleading logarithms.