The performance of the geant4 standard EM package for LHC and other applications

Recent Progress of Geant4 Electromagnetic Physics and Readiness for the LHC Start

“…Thus, by keeping practically the same CPU performance, a better agreement between simulation and data for the backscattering of electrons is achieved. In Fig.2 it is shown that both new MSC and the single scattering model [7] are close to the measurements. Note that a simulation using the single scattering process requires much more CPU, because of sampling of each elastic collision.…”

“…The Geant4 multiple scattering model (MSC) was under development for the last several years [7,13] with a focus on providing the best balance between accuracy and CPU performance, which is a critical requirement for the LHC simulation. Recent modifications concentrated on implementing and tuning of MSC models specific to particle type, with electrons as our first goal.…”

“…Various infrastructure upgrades of the EM software have been performed: the validation suite [7] was further extended; new helper classes were designed; extra options were introduced. In particular, a cubic spline interpolation of physics tables was provided, which is an alternative to the existing linear interpolation.…”

“…It has been used for many years in different applications, in particular, for Monte Carlo simulation of experiments in high energy physics [3][4][5][6]. Many efforts were concentrated on the preparing of the Geant4 EM physics package specifically for the LHC [7]. Recent improvements accomplished a better description of details of the EM physics.…”

Recent Developments in Geant4

“…As such, recent versions of GEANT4 have this combined model set as the default for muon and hadron transport, and for ± e above 100 MeV. Validation of multiple scattering models for muons and hadrons are published elsewhere [34,57,70,74].…”