Interfacing EGS4 with Geant4 for comparison of physics processes in the two different simulation tools

There are several well-known and widely-used simulation packages. However, comparing between different simulation tools often raises controversial issues. Geant4 has rich flexibility and expansibility brought by its Object-Oriented approach, especially in adding physics processes. We can use Geant4 as a framework and plug-in the part of physics processes of other packages as Geant4 modules. In this paper, we focused on interfacing EGS4 with Geant4. EGS4 is one of the most wellknown simulation packages for electromagnetic physics. Taking advantage of the capability of Geant4 as a framework, we developed a plug-in interface for using EGS4 as a module of Geant4 physics process. This is useful and important for making comparisons between EGS4 and Geant4 especially in users' application level. In this paper, we describe our approach of design and implementation of the interface, and the results of basic benchmarks are also presented.