New Geant4 based simulation tools for space radiation shielding and effects analysis презентация

New Geant4 based simulation tools for space radiation shielding and effects analysis. 8th Topical Seminar on Innovative Particle and Radiation Detectors 21 - 24 October 2002 Siena, Italy

Space radiation environment Trapped radiation Electrons ~< 10 MeV Protons ~< 102 MeV Solar radiation Protons, heavy ions, electrons, neutrons, gamma rays, X-rays… Cosmic rays Lower intensity Heavy ions

Radiation effects and analysis tools Current tools include: SPENVIS – models of space environment & basic effects analysis (ESA/BIRA) CREME96 – Cosmic Ray/SEU analysis (NRL) SIREST – space environment analysis for Shuttle missions (NASA/LaRC) SEDAT (Space Environment Data Analysis Tool) – databases of space environment data & tools for analysis. (ESA/RAL) ESABASE/Radiation Space Systems Analyser …

SSAT Sector Shielding Analysis Tool Geant4 based application Ray-tracing analysis of a user-defined geometrical configuration Produces: distributions of shielding material and thickness as viewed from a given point within the configuration as a function of direction from that location. This approach is highly useful for calculating the absorbed radiation dose, and for finding optimal shielding geometries.

Geant4 CAD Front-End tool Professional CAD tools are common in the aerospace industry STEP files import MC-related material information is not included in the STEP file Materials and Geometry Association (MGA) tool a Java-based utility graphical user-interface (GUI) material definitions from an existing database of common spacecraft materials new materials in terms of elemental or nuclear composition.

CAD Front-End Tool: the SREM case SREM geometry imported from STEP files Comparisons to Geant3 Calibration data

Reat project Radiation Effects Analysis Tools Develop a new generation of radiation shielding and effect tools for civil space applications Based on Geant4 Complete treatment of secondary particles Completeness of physics list List of sub-projects MULASSIS (MUlti-LAyer Shielding Simulation S/W): Geant4 application for dose and particle fluence analysis associated with the use of radiation shields (more advanced than SHIELDOSE). GeMAT (Geant4-based Microdosimetry Analysis Tool ): Geant4 application for detailed study of radiation on microelectronic devices.

MULASSIS MUlti-LAyer Shielding Simulation Software Need for better description of the impact of space environment on the spacecrafts Detailed radiation effects analysis in a multi-layer geometry Increasing mass  secondaries more and more important Difficult to take into account with analytical models or look-up table approach (SHIELDOSE) User-friendly (to non C++ programmers) Basic Space-Environment options included Integrated into SPENVIS with a WWW interface

MULASSIS: Physics lists Physics description includes EM (std or LowEnergy extension) hadron/nuclear interaction (parameterised, precompound) neutron transport Kinetic and HETC models coming for energies ~< 10 GeV/nucleon

MULASSIS: geometry scripting, primaries and visualization Interactive version Scripting to build the geometry layers Predefined or user defined materials

MULASSIS: integration in SPENVIS First web interface to Geant4! Geometry definition Layer number, depth and material Physics list choice Primary particle spectrum and fluences from SPENVIS Trapped protons Solar protons Trapped electrons Analysis options Pulse Height Spectrum Ion. dose NIEL

MULASSIS: an example inside the SPENVIS interface SPENVIS orbit input parameters LEO circular orbit altitude 500 km inclination 28 deg

MULASSIS: output Particle fluence as a function of particle species, energy, angle and boundary between the layers. Non-ionising energy loss (NIEL) based on the fluence and CERN NIEL coefficients. Energy deposition in the layer or ionising dose in the layer. Pulse-height energy deposition in the layer.

MULASSIS: comparisons Comparison with MCNPX Good agreement in secondary radiation spectra Introduction of kinetic ant HETC models in the next release will eliminate the disagreement in the neutrons

GeMAT Geant4-based Microdosimetry Analysis Tool Simulate microdosimetry in geometries representing features of a semiconductor device (transistor/junction geometries) Proton (nuclear and electromagnetic), and electron interactions in the energy range applicable to microdosimetry effects induced by the space radiation environment Analysis includes single event effects in semiconductor devices simultaneous energy deposition in several sensitive regions

Future developments SpaceGRID Space science, Earth observation, Space weather and Spacecraft engineering MULASSIS is being ported to the GRID Prototype ready New ESA contract: Energetic Particle Shielding and Interactions Software, major R&D item. 5 ESA Science missions 5 other activities for Geant4 development and applications

Summary Role of Geant4 in the space domain SSAT, CAD Front-End tool, MULASSIS, GeMAT Future developments (SpaceGRID, …) Geant4 Space Users’ Forum 20-22 January 2003 at ESTEC: http://www.estec.esa.nl/conferences/03C05/index.html