In Monte Carlo particle transport codes, it is often important to adjust reaction cross sections to reduce the variance of calculations of relatively rare events, in a technique known as non-analogous Monte Carlo. We present the theory and sample code for a Geant4 process which allows the cross section of a G4VDiscreteProcess to be scaled, while adjusting track weights so as to mitigate the eff...

We describe a scalable parallelization of Geant4 using commodity hardware in a collaborative effort between the College of Computer Science and the Department of Physics at Northeastern University. The system consists of a Beowulf cluster of 32 Pentium II processors with 128 MBytes of memory each, connected via ATM and fast Ethernet. The bulk of the parallelization is done using TOP-C (Task Ori...

The GEANT4 Monte Carlo code has been used to simulate gamma-ray spectra of natural radionuclides collected by a NaI scintillation detector immersed in seawater. The gamma-rays emitted from the decay of (40)K, and the series of (232)Th and (238)U, were used to describe the radioactive water source around the NaI crystal. The simulated gamma-ray spectra were compared with real data recorded in si...

The abBA collaboration proposes to conduct a comprehensive program of precise measurements of neutron β-decay coefficients a (the correlation between the neutrino momentum and the decay electron momentum), b (the electron energy spectral distortion term), A (the correlation between the neutron spin and the decay electron momentum), and B (the correlation between the neutron spin and the decay n...

This paper presents a hybrid simulator for the fast calculation of x-ray projections. Uncollided radiations are determined with a ray-driven method whereas the scattering signal is partitioned into single and multiple scattering, respectively estimated with an accelerated deterministic method and a coarse Monte Carlo simulation. The simulator takes into account the full acquisition chain, from ...

Thread-parallelisation and single-instruction multiple data (SIMD) ”vectorisation” of software components in HEP computing has become a necessity to fully benefit from current and future computing hardware. In this context, the Geant-Vector/GPU simulation project aims to re-engineer current software for the simulation of the passage of particles through detectors in order to increase the overal...

The Virtual Monte Carlo concept allows performing simulations using Geant3, Geant4 or Fluka without changing the user code [1]. This concept was used as a base for developing the CbmRoot framework for the CBM collaboration [2]. In this concept, the same framework is used for simulation and data analysis. An Oracle database with a build-in versioning management is used to efficiently store the d...

In the course of its operation, the Volcano Ranch array collected data on the lateral distribution of showers produced by cosmic rays at energies above 10 eV. From these data very precise measurements of the steepness of the lateral distribution function, characterized by the η parameter, were made. The current availability of sophisticated hadronic interaction models has prompted a reinterpret...

Compton scattering models in Geant4 are the following: a.) G4ComptonScattering: listed as ”compt” in the process name. No Rayleigh scattering in the model. b.) G4LowEnergyCompton: Process name is ”LowEnCompton” in the tracking code. It has errors in the treatment of Rayleigh scattering and does not account for Doppler broadening (the effect of bound electron momentum on the scattered particle e...

Using Geant4 Monte-Carlo simulations the potential of the Low Energy Neutrino Astronomy (LENA) liquid scintillator detector for the investigation of a possible proton decay within the channel p → Kν is discussed. Special emphasis is given to the study of background events.