Presentation on theme: "G.Santin, P Nieminen, H Evans, E Daly"— Presentation transcript:
1 New Geant4 based simulation tools for space radiation shielding and effects analysis. G.Santin, P Nieminen, H Evans, E Daly(ESA-ESTEC, Noordwijk, The Netherlands)F Lei, P R Truscott, C S Dyer(QinetiQ, Farnborough, England)B Quaghebeur, D Heynderickx(BIRA, Brussels, Belgium)8th Topical Seminar on InnovativeParticle and Radiation DetectorsOctober 2002Siena, Italy
2 Space radiation environment Trapped radiationElectrons ~< 10 MeVProtons ~< 102 MeVSolar radiationProtons, heavy ions, electrons, neutrons, gamma rays, X-rays…Cosmic raysLower intensityHeavy ionsG.Santin Siena, 21 Oct 2002Environment particles cause radiation damage to electronic components, solar cells and materialsEffects include:Surface chargingSingle Event Upset / Latch UpIncreased backgroundDegradation, dose, solar cell, NIELDNA (biological) damageOther environment components (energetic and low-energy plasma, Oxygen atoms, debris) here neglected
3 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…G.Santin Siena, 21 Oct 2002The role ofSpecific applications developed to address particular itemsTrapped/solar radiation, cosmic rays, spacecraft chargingSSAT, CAD Front-End, REAT/MULASSIS“Generic engineering tool” approachMore detailed analysis tools (ESA/Qinetiq/BIRA)XMMThe first satellite failure due to total dose was the Telstar. Telstar was launched a day after the July 9, 1962 Starfish nuclear test. The Starfish, a nuclear weapon of 1.4 Megaton strength, was detonated at an altitude of about 325 nmi (above Johnston Island in the Pacific). The explosion produced beta particles (electrons) that were injected into the earth's magnetic field and which formed an artificial radiation belt. This artificial electron belt lasted until the early 1970s. The Telstar experienced a total dose 100 times that expected due to the weapon test. Starfish destroyed seven satellites within 7 months primarily from solar cell damage.
4 SSAT Sector Shielding Analysis Tool G.Santin Siena, 21 Oct 2002Geant4 based applicationRay-tracing analysis of a user-defined geometrical configurationProduces:distributions of shielding material and thickness as viewedfrom a given point within the configurationas a function of direction from that location.This approach is highly useful for calculating the absorbed radiation dose, and for finding optimal shielding geometries.
5 Geant4 CAD Front-End tool Professional CAD tools are common in the aerospace industrySTEP files importMC-related material information is not included in the STEP fileMaterials and Geometry Association (MGA) toola Java-based utilitygraphical user-interface (GUI)material definitionsfrom an existing database of common spacecraft materialsnew materials in terms of elemental or nuclear composition.G.Santin Siena, 21 Oct 2002South Atlantic Anomaly (SAA)“Polar horns”First / PlanckintegralPROBArosettaUsed to import the SREM geometry (Standard Radiation Environment Monitor)SREM is flying on PROBA and INTEGRAL (+ ROSETTA,…)PROBA
6 CAD Front-End Tool: the SREM case G.Santin Siena, 21 Oct 2002SREM geometry imported from STEP filesComparisons toGeant3Calibration data
7 Reat project Radiation Effects Analysis Tools Develop a new generation of radiation shielding and effect tools for civil space applicationsBased on Geant4Complete treatment of secondary particlesCompleteness of physics listList of sub-projectsMULASSIS (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.G.Santin Siena, 21 Oct 2002
8 MULASSIS MUlti-LAyer Shielding Simulation Software G.Santin Siena, 21 Oct 2002Need for better description of the impact of space environment on the spacecraftsDetailed radiation effects analysis in a multi-layer geometryIncreasing mass secondaries more and more importantDifficult to take into account with analytical models or look-up table approach (SHIELDOSE)User-friendly (to non C++ programmers)Basic Space-Environment options includedIntegrated into SPENVIS with a WWW interface
9 MULASSIS: Physics lists Physics description includesEM (std or LowEnergy extension)hadron/nuclear interaction (parameterised, precompound)neutron transportKinetic and HETC models comingfor energies ~< 10 GeV/nucleonG.Santin Siena, 21 Oct 2002
10 MULASSIS: geometry scripting, primaries and visualization Interactive versionScripting to build the geometry layersPredefined or user defined materialsG.Santin Siena, 21 Oct 2002TitaniumAluminumCarbon fiberSilicon detectorFig. 2. A screen shot of the MULASSIS visualisation window. The shield shown here is made of three layers (titanium, aluminium and carbon fibre from left to right) and a thin silicon detector layer is placed behind the carbon fibre layer. Superimposed on top of the geometry are the interaction tracks of 1 GeV protons incident from the left.1 GeV Protons
11 MULASSIS: integration in SPENVIS First web interface to Geant4!Geometry definitionLayer number, depth and materialPhysics list choicePrimary particle spectrum and fluences from SPENVISTrapped protonsSolar protonsTrapped electronsAnalysis optionsPulse Height SpectrumIon. doseNIELG.Santin Siena, 21 Oct 2002Fig. 3. User interfaces in SPENVIS for MULASSIS. All command-line input options have been converted into web-form format. Users can simply fill in their simulation parameters including geometry and material definition, physics module selection and cut-offs, and analysis requirements (as shown in the figure). All fields are with default values or the user can select from a list of predefined values.
12 MULASSIS: an example inside the SPENVIS interface SPENVIS orbit input parametersLEO circular orbitaltitude 500 kminclination 28 degG.Santin Siena, 21 Oct 2002SPENVIS outputTrapped proton and electron fluxesSolar proton fluenceTrajectory average spectra1.00E-021.00E-011.00E+001.00E+011.00E+021.00E+031.00E+041.00E+050.010.11101001000Energy (MeV)Differential flux (/cm2/s/MeV)electronsprotons
13 MULASSIS: output Particle fluence Non-ionising energy loss (NIEL) 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.G.Santin Siena, 21 Oct 2002Fig. 9. Dose-depth curve in a silicon layer exposed to the trapped electrons. No shielding used in the MULASSIS simulation.Fig Non-Ionising Energy Loss in the Si detector due to the secondary protons, neutrons and electrons after Al shield of various thicknesses. Damage by protons is dominant, but neutrons make an increasing contribution in thick shield cases.Doses: ionizationDose-depth curveDisplacement damage (NIEL)Si (or Si equivalent)
14 MULASSIS: comparisons Comparison with SHIELDOSE-2Total ionising doses for the Si detector behind Al shield of various thicknessestrapped proton from SPENVISG.Santin Siena, 21 Oct 2002Comparison with MCNPXGood agreement in secondary radiation spectraIntroduction of kinetic ant HETC models in the next release will eliminate the disagreement in the neutronsFig. 8. Total ionising doses for the Si detector behind Al shield of various thicknesses. For comparison doses predicated by SHIELDOSE-2 for the same trapped proton source are also plotted.Fig. 5. Secondary particle fluence energy spectra behind a 1mm aluminium shield. The incident particles are the trapped electrons for one year as also shown in the figure. The spectra were produced by simulation using 107 electrons. Fluctuations at the low energy end of the spectra are statistical. Also shown in the figure are the MCNPX derived electron and gamma ray spectra. Excellent agreement has been achieved between the two gamma ray spectra, but a factor of 2 difference is observed in the emerging electron spectra.Fig. 6. A comparison of the secondary proton and neutron spectra derived by MULASSIS and MCNPX simulations. Trapped protons are the incident particle. Overall agreement is achieved, for the protons in particular. There are some differences in the neutron spectra and this is a reflection of the different physics model used in the two codes, Pre-Compound model in the case of MULASSIS and HETC intra-nuclear cascade model in the MCNPX code.
15 GeMAT Geant4-based Microdosimetry Analysis Tool G.Santin Siena, 21 Oct 2002Simulate 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 environmentAnalysis includessingle event effects in semiconductor devicessimultaneous energy deposition in several sensitive regionsPrototype readyWill be integrated into the ESA SPENVIS web-based space environment simulation tool-set
16 Future developments SpaceGRID Space science, Earth observation, Space weather and Spacecraft engineeringMULASSIS is being ported to the GRIDPrototype readyNew ESA contract: Energetic Particle Shielding and Interactions Software, major R&D item.5 ESA Science missions5 other activities for Geant4 development and applicationsG.Santin Siena, 21 Oct 2002ESA’s SpaceGRIDDozens of satellites are constantly collecting data about our planetary system - the Earth in particular - 24 hours a day 365 days a year. Satellite data is used for many purposes, for example for telecommunications, navigation systems and environmental monitoring. However, even with the most powerful computers processing all this data is time-consuming and expensive. Distributing these tasks over a number of low-cost internet-connected platforms would provide enormous potential, at a relatively low cost, for many space applications.To look into this exciting possibility ESA is about to begin work on its SpaceGRID project. This will be run by an international consortium of industry and research centres led by Datamat (Italy). Other members include Alcatel Space (France), CS Systemes d’Information (France), Science Systems Plc (UK), QinetiQ (UK) and the Rutherford Appleton Laboratory of the UK Council for the Central Laboatory of the Research Councils.The project aims to assess how GRID technology can serve requirements across a large variety of space disciplines, sketch the design of an ESA-wide GRID infrastructure, foster collaboration and enable shared efforts across space applications. It will analyse the highly complicated technical aspects of managing, accessing, exploiting and distributing large amounts of data, and set up test projects to see how well the GRID performs at carrying out specific tasks in Earth observation, space weather, space science and spacecraft engineering.The results of the study should be available within 18 months, but meanwhile ESA will be kept informed of the progress being made and project activities will be synchronised with the ESA internal GRID initiative.Two other aspects of this project are of particular importance for ESA: finding a way to ensure that the data processed by the SpaceGRID can be made available to public and educational establishments, and ensuring that SpaceGRID activities are coordinated with other major international initiatives. This is one reason why the October meetings of the DataGRID and the Global Grid Forum are of particular interest to ESA.
17 Summary Geant4 Space Users’ Forum 20-22 January 2003 at ESTEC: Role of Geant4 in the space domainSSAT, CAD Front-End tool, MULASSIS, GeMATFuture developments (SpaceGRID, …)Geant4 Space Users’ Forum January 2003 at ESTEC:G.Santin Siena, 21 Oct 2002