The motivation of the project was to provide a mock-up of a typical Geant4 simulation application. Something that preserves the most important algorithmic and computing characteristics of a typical Geant4 based particle transport simulation while exposes the underlying main computing flow, algorithms and components in a clear and simple way. The primary goal was to provide a starting point, a sandbox that can be easily utilised even by non-experts for initial testing, trying new technologies, techniques targeting Geant4 based simulation applications in order encourage, stimulate and facilitate such activities.
HepEmShow provides a minimalist, simplistic but complete and self contained implementation of a Geant4 like but Geant4 independent simulation application for modelling High Energy Physics(HEP) style electromagnetic(EM) shower(SHOW) in a configurable, simplified sampling calorimeter illustrated below.
Beyond the usual application specific simulation components (e.g. application geometry or primary particle/event generation description), HepEmShow also includes a minimalist and simplistic but local implementation of all necessary, general Geant4 kernel components (e.g. event processing or stepping loops). This makes HepEmShow self contained and complete allowing to alter and change the underlying computing flow, components and algorithm at any points.
It must be noted, that while HepEmShow is a Geant4 independent EM shower simulation, the provided results agree very well to those obtained by the corresponding Geant4 based simulation as illustrated below.
The only requirement, that already allows to build and execute the HepEmShow simulation application (using the default material configuration of the calorimeter), is G4HepEm. It is actually G4HepEm that makes possible to develop such a Geant4 like but Geant4 independent EM shower simulation like HepEmShow. See more details in the corresponding part of the Build and Install section of the Documentation or jump to Quick start.