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## SPENVIS Integration of Mulassis

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**SPENVIS Integration of Mulassis**H.D.R. Evans Space Environments and Effects Section TEC-EES**What is Mulassis? What can it Do?**What is Mulassis: • A 1-D geometrical Monte-Carlo application • Based on the Geant4 toolkit • Simple, easy to use. What can it Do? • Simulates energetic particle interactions in 1-D geometries (slab/sphere) • Includes physical models and material properties of Geant4. • Calculates total dose, NIEL, shielded fluences, PHS, Dose-Equivalent • Can be used determine dose, c.f. SHIELDOSE, but for shields other than Aluminium. SPENVIS Integration of Mulassis - SPENVIS Workshop**Spenvis/Local Version**• Can run via SPENVIS interface • Easy to use, simplified inputs • Can directly include radiation environment spectra • Can download from REAT server, install and run as a standalone application • Can run simulations with more events • Greater flexibility in specifying input parameters. • No network connection required • Useful for parametric analyses SPENVIS Integration of Mulassis - SPENVIS Workshop**Spenvis/Mulassis:http://www.spenvis.oma.be/spenvis/**• Accessed via the SPENVIS Server. • Provides a series of Web pages to set up a simulation • Geometry definition • Particle source definition • Physics to include in simulation • Novice user has simpler options • Advanced user can set production cuts (by region), selection of physics models • Output analysis specification (one type per run, which simplifies the interface) • Plotting of outputs • Provides the G4MAC file that can be used directly in a local Mulassis run. • Caveat: The space environment spectra vary by several orders of magnitude over their energy range -> leads to oversampling of non-effectual low-energy particles to the detriment of high energy ones; energy biasing of spectra would be very useful, but is still to be implemented. SPENVIS Integration of Mulassis - SPENVIS Workshop**Standalone Mulassis**• Download it from http://reat.space.qinetiq.com/mulassis/mulassis.htm • Linux and Win32 binary versions available. (Win32 split into two install wizards: G4data and Mulassis) • Statically linked Linux version is available – saves installing Geant4 and rebuilding Mulassis – should run on most Linux boxes – does not include OpenGL. • Provides more functionality and flexibility than available with SPENVIS, e.g. energy/angular biasing of GPS particle source. SPENVIS Integration of Mulassis - SPENVIS Workshop**Geometry Specifications**• Default – SHIELDOSE Slab with layers commensurate with SD shielding thicknesses • Planar Slab • Spherical Shell SPENVIS Integration of Mulassis - SPENVIS Workshop**Geometry Specification**• 1-D geometries used: Slab/Sphere:/geometry/layer/shape [slab|sphere] • Layers specified by:/geometry/layer/add <layerNo> <Material> <colour> <thick> <thick_units>/geometry/layer/add 0 Aluminium 1 4.0 mm/geometry/layer/add 1 Silicon 2 50 mum • Other commands include: • /geometry/layer/delete <layerNo> • /geometry/layer/list SPENVIS Integration of Mulassis - SPENVIS Workshop**SPENVIS Geometry Interface**SPENVIS Integration of Mulassis - SPENVIS Workshop**Material Specification/geometry/material**• Predefined Materials: • Vacuum • Air • Aluminium • Silicon • Adding new materials: • /geometry/material/add <Name> <Chem. Formula> <density g/cm3> • /geometry/material/add fused_quartz Si-O2 2.200E+00 SPENVIS Integration of Mulassis - SPENVIS Workshop**SPENVIS Materials Interface**SPENVIS Integration of Mulassis - SPENVIS Workshop**Incident Particle Specification**• Easiest: Use SPENVIS to set up the General Particle Source (GPS) macros. • Establish particle type:/gps/particle [ion|proton|neutron|e-|…] • Establish particle source shape (point source) • Establish angular distribution (isotropic -> cosine law)/gps/ang/type cos • Establish particle spectrum (mono, data, eEnergy, …), Emin, Emax • Optional: • Energy Biasing • Angular Biasing • Etc. • See the GPS documentation SPENVIS Integration of Mulassis - SPENVIS Workshop**Normalisation Factor**• What is it? • It’s a factor to scale the Mulassis outputs to the environment -> to provide the real dose/fluence. • Total number of environmental particles in simulation energy range that would impact per cm2. • E.g. NF = ¼ [Flux(>10 MeV) – Flux(>100 MeV)] • New version of SPENVIS calculates this automatically from environment spectra. SPENVIS Integration of Mulassis - SPENVIS Workshop**Spenvis Source Particles**SPENVIS Integration of Mulassis - SPENVIS Workshop**Spenvis Source Particles**SPENVIS Integration of Mulassis - SPENVIS Workshop**Physics to include/phys/scenario <scenario>**• Electro-Magnetic /“Lepton-gamma transport” (em) • Low Energy Electro-Magnetic (leem) • Hadrons (hadron) • Low Energy Neutrons (+/- ln) • Binary Cascades (binary) • For Example, for hadron AND electro-Magnetic but NO low energy neutrons: /phys/scenario hadron+em-ln See Mulassis User Manual for more documentation SPENVIS Integration of Mulassis - SPENVIS Workshop**SPENVIS Physical Models**SPENVIS Integration of Mulassis - SPENVIS Workshop**Analysis Types**• Fluence – shielded particle spectra • Dose – Total dose in layer/shell • Dose Equivalent: ICRP-60 Q(L) definition • Non-Ionising Energy Loss (NIEL) Dose in layer interface • Pulse Height Spectrum (PHS) SPENVIS Integration of Mulassis - SPENVIS Workshop**Fluence Analysis**• Calculation of the shielded flux spectrum for a particle. • This is the number of particles crossing a layer boundary. • Data is the number of particles counted per energy bin -> divide by the bin width to get the differential spectrum. SPENVIS Integration of Mulassis - SPENVIS Workshop**SPENVIS Fluence Analysis**SPENVIS Integration of Mulassis - SPENVIS Workshop**Dose Analysis**• Calculates the total energy deposited in a layer. • Numerous units available: MeV, Rads, Gy, etc. • Can be compared to SHIELDOSE outputs : (60 day GTO Trapped proton spectrum, 2 mm Al. shield, Si target) • Mulassis: 1711 ± 427 Rads • SD-2: 1880 Rads SPENVIS Integration of Mulassis - SPENVIS Workshop**SPENVIS Dose Analysis**SPENVIS Integration of Mulassis - SPENVIS Workshop**SPENVIS Dose Analysis**SPENVIS Integration of Mulassis - SPENVIS Workshop**NIEL Analysis**• Uses various NIEL curves to calculate the NIEL in an interface between two layers from the Fluence analysis. • Limited to NIEL analyses for specific curves: • SPENVIS/JPL proton curve • CERN/ROSE curves for protons, electrons, neutrons, pions • SAVANT/NRL curves for protons, electrons & neutrons in Silicon, GaAs, and InP (c.f. S. Messenger presentation yesterday). • Can now set NIEL curve by layer. • This is unlike the DOSE analysis, which calculates the total energy deposited in the layer. • For thin targets, this should be adequate. SPENVIS Integration of Mulassis - SPENVIS Workshop**SPENVIS NIEL Analysis**SPENVIS Integration of Mulassis - SPENVIS Workshop**PHS Analysis**• A “cross” between the dose and fluence analysis: it provides the number of particles that deposit a specific energy in an energy bin. • Used to predict the energy deposited spectra in, for example a silicon detector. SPENVIS Integration of Mulassis - SPENVIS Workshop**SPENVIS PHS Analysis**SPENVIS Integration of Mulassis - SPENVIS Workshop**SPENVIS PHS Analysis**SPENVIS Integration of Mulassis - SPENVIS Workshop**Dose Equivalent Analysis**• Not yet implemented in SPENVIS • Uses ICRP-60 Q(L) function to calculate Dose Equivalent • Deviates from standard for H*(d) due to geometry simplifications: H(d) in Mulassis is calculated for the whole spherical shell, not just the solid angle along a particular direction. Pelliccioni, M. “Overview of Fluence-to-Effective Dose and Fluence-to-Ambient Dose Equivalent Conversion Coefficients for High Energy Radiation Calculated Using the FLUKA Code”, Radiat. Prot. Dosim. 88(4), 279-297 (2000) SPENVIS Integration of Mulassis - SPENVIS Workshop**Visualisation**• Most useful are: • OpenGL: X windows visualisation on the screen as simulation runs. • VRML2FILE: visualisation within VRML viewer (Cortona plugin, vrmlview for Linux)* • DAWN: with the dawn application, can produce postscript files. • WIRED • Static binary version does not support OpenGL. • Only the first 100 events will be displayed. *my preferences SPENVIS Integration of Mulassis - SPENVIS Workshop**Output Files**• Mulassis G4 Macro File • Report file • Contains information about run • Dose and NIEL results • Comma Separated Value (CSV) file • In SPENVIS CSV format • Contains outputs from all analysis modules (dose, PHS, Fluence and NIEL) • Program output/log file SPENVIS Integration of Mulassis - SPENVIS Workshop**Spenvis Output Page**SPENVIS Integration of Mulassis - SPENVIS Workshop**SPENVIS Mulassis Macro**/gps/hist/point 5.000E+00 5.061E+04 /gps/hist/point 6.000E+00 2.858E+04 /gps/hist/point 7.000E+00 1.771E+04 /gps/hist/point 1.000E+01 6.902E+03 /gps/hist/point 1.500E+01 1.603E+03 /gps/hist/point 2.000E+01 4.551E+02 /gps/hist/point 3.000E+01 9.342E+01 /gps/hist/point 4.000E+01 3.074E+01 /gps/hist/point 5.000E+01 1.888E+01 /gps/hist/point 6.000E+01 1.085E+01 /gps/hist/point 7.000E+01 8.428E+00 /gps/hist/point 1.000E+02 5.459E+00 /gps/hist/point 1.500E+02 2.826E+00 /gps/hist/point 2.000E+02 1.595E+00 /gps/hist/point 3.000E+02 5.442E-01 /gps/hist/point 4.000E+02 3.608E-02 /gps/hist/inter Lin /gps/ang/type cos /gps/ang/mintheta 0.000E+00 deg /gps/ang/maxtheta 9.000E+01 deg /vis/open VRML2FILE /vis/scene/create /vis/viewer/set/style wireframe /vis/viewer/set/viewpointThetaPhi 90. 180. /vis/drawVolume /vis/scene/endOfEventAction accumulate /tracking/storeTrajectory 1 /event/printModulo 1000 /run/cputime 6.000E+02 /run/beamOn 10000 # SPENVIS generated macrofile for MULASSIS /geometry/layer/delete 0 /geometry/material/add ICRU_Tissue H5398-C498-N100-O2566 1.000E+00 /geometry/layer/shape slab /geometry/layer/add 0 Aluminium 1 2.000E+00 mm /geometry/layer/add 1 Silicon 2 1.000E+01 mum /geometry/layer/add 2 Silicon 1 1.000E+01 mum /geometry/layer/add 3 Silicon 1 1.000E+01 mum /geometry/layer/add 4 Silicon 1 1.000E+01 mum /analysis/file spenvis /analysis/normalise 8.188E+13 cm2 /analysis/phs/add 2 /analysis/phs/add 3 /analysis/phs/add 4 /analysis/phs/energy/default /geometry/update /phys/scenario em /gps/particle proton /gps/ene/type Arb /gps/hist/type arb /gps/ene/min 1.000E-01 MeV /gps/ene/max 4.000E+02 MeV /gps/hist/point 1.000E-01 3.056E+08 /gps/hist/point 1.500E-01 2.336E+08 /gps/hist/point 2.000E-01 1.724E+08 /gps/hist/point 3.000E-01 1.012E+08 /gps/hist/point 4.000E-01 6.619E+07 /gps/hist/point 5.000E-01 4.443E+07 /gps/hist/point 6.000E-01 3.149E+07 /gps/hist/point 7.000E-01 2.327E+07 /gps/hist/point 1.000E+00 1.153E+07 /gps/hist/point 1.500E+00 3.808E+06 /gps/hist/point 2.000E+00 1.474E+06 /gps/hist/point 3.000E+00 3.337E+05 /gps/hist/point 4.000E+00 1.176E+05 SPENVIS Integration of Mulassis - SPENVIS Workshop**CSV File Format**• SPENVIS Comma Separated Value (CSV) format:http://spenvis.oma.be/spenvis/help/models/outputs.html#UNIFMT • Can be directly imported into Excel • Header lines/Meta Data • “navigation info”: # variable, header lines, data lines, … • Plotting annotation • Data variable descriptions: name, units, dimensions, description • Data in columns SPENVIS Integration of Mulassis - SPENVIS Workshop**Misc.**• SPENVIS – download output files directly into Excel • Use SPENVIS to set up simulation and then tailor the macro file to your own ends. • Material “calculator” Excel Spreadsheet (G. Santin) • CREME-86 Excel implementation of M1 environment to provide GCR Spectra • “help” command in command line version. SPENVIS Integration of Mulassis - SPENVIS Workshop**Future Activities/Desires:**• Provide GCR spectra via SPENVIS/MULASSIS “Source Particles” page. • Include physics to handle high energy ions (E>10 GeV/n). • Provide energy biasing of spectra. • Include Köln NIEL developments to calculate NIEL directly during simulation. • Solar Cells: • Include SAVANT Solar Cell degradation calculation as an analysis output- not just the NIEL damage output. • Implement a simplified interface for solar cell engineer in SPENVIS • Include Nuclear Decay Model. • Implement Dose Equivalent Analysis in SPENVIS. SPENVIS Integration of Mulassis - SPENVIS Workshop**Questions?**SPENVIS Integration of Mulassis - SPENVIS Workshop**Demonstration**• Spenvis simulation • Command line (local) simulation • Excel spreadsheets: • Normalisation factor • Material properties • CREME M1 spectra SPENVIS Integration of Mulassis - SPENVIS Workshop