On hadronic shower simulation

The exploitation of hadronic final states played a key role in the successes of all recent HEP collider experiments, and the ability to use the hadronic final state will continue to be one of the decisive issues during the LHC era. Monte Carlo techniques to make efficient use of hadronic final states have been developed for many years, and have a technological culmination in object oriented tool-kits for hadronic shower simulation that now are becoming available. In the present paper we give a brief overview on the physics modeling underlying hadronic shower simulation, and report on advanced techniques used and developed for simulation of hadronic showers in HEP experiments. We will discuss the three basic types of modelling - data driven, parametrisation driven, and theory driven modelling - and demonstrate ways to combine them in a flexible manner for concrete applications. We will confront the different types of modelling with the stringent requirements on hadronic shower simulation posed by LHC, and investigate whether the issue will have been addressed in a satisfactory manner within time restrictions of the computing technical design reports of the LHC experiments. (25 refs).