Design and performance evaluations of generic programming techniques in a R&D prototype of Geant4 physics

Abstract

Geant4 is nowadays a mature Monte Carlo system; new functionality has been extensively added to the toolkit since its first public release in 1998, nevertheless, its architectural design and software technology features have remained substantially unchanged since their original conception in the RD44 phase of the mid ‘90s. A R project has been recently launched at INFN to revisit Geant4 architectural design in view of addressing new experimental issues in HEP and other related physics disciplines, as well as existing concerns in the present Geant4 technological environment. One of the items in this project investigates the use of generic programming techniques besides the conventional object oriented methods currently used in Geant4 to address some significant issues emerged in the first 10 years’ experience of Geant4 experimental applications. Some of the topics addressed are the customization of physics modeling in a simulation application, scattered and tangled concerns across the code, computational performance, intrinsic testing capabilities embedded in physics objects, automated quality assurance features, data handling optimization etc.. Software design features and preliminary results from a new prototype implementation of Geant4 electromagnetic physics and physics data handling packages exploiting generic programming techniques are illustrated. Performance evaluations concerning the use of dynamic or static polymorphism in concrete simulation use cases are presented. Programming solutions addressing quality assurance issues in Geant4 physics modeling are discussed.