Outline of recent ESA-related developments Giovanni Santin *, Petteri Nieminen ESA / ESTEC *RHEA System SA GEANT4 – SPENVIS Space Users’ Workshop ‘06 Pasadena, 9-10 November 2006

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov Geant4 for space environment analyses Environments – Physics - Geometry - Analysis ESA involvement in the Geant4 collaboration (since 1997) contributed to new capabilities in the Geant4 kernel of relevance for space applications and tools in the space radiation environments and effects domain. Applications: Science mission analyses Radiation engineering and shielding applications Planetary environment modelling Human effects Physics Usability Geometry modelling

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov Physics New requirements from –Science missions –Human space flight –Effects to micro-electronics –Environment modelling

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov Space environment and Physics models 100 eV1 keV10 MeV100 MeV100 GeV100 TeV100 PeV Tr. Protons Tr. Electrons Solar protons Cosmic rays: p, ,ions Extreme Energy Cosmic Rays Plasma Space environment Geant4 models HAD protons HAD ions EM Standard EM Low Energy Optical

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov Physics developments Ion physics –P. Truscott, REAT_MS 1, MARSREM Very low energy extensions –MG Pia, Geant4-DNA Physics lists for space applications –V. Ivantchenko, REAT_MS 1 Inverse Monte Carlo –Laurent Desorgher, REAT_MS 1 & 2 See related talks at this workshop

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov Geant4 Reverse MC “Adjoint” technique [Kalos 1968] New transport equation, “adjoint” to the conventional “forward” transport equation Transport analogous to the forward one, but backward –successive points are higher in energy, earlier in time Suitable for Monte Carlo calculations Computations start at the detector and score at the source Possibility of computing doses at a point! Feasibility study (REAT_MS 1) G4 RMC Prototype for fast e- dose computation Only continuous energy loss and simple multiple scattering Completed Full implementation (REAT_MS 2) RMC in G4 for fast e- dose computation Backward simulation of : –e- ionisation with delta production, continuous energy loss and multiple scattering –Bremstrahlung, compton scattering, photo-electric effect In development - Release mid 2007 Laurent Desorgher Space IT and Uni. Bern Proposed to be included in Geant4 release

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov Geometry GDML –Upgrades –Developments for CAD I/F CAD –Prototype interface through ST-Viewer –GDML Interface in Space Engineering CAD tools ESABASE1 –Through ES9 meshing –Under investigation

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov GDML Geometry Description Markup Language Initial frame: XML based geometry description for Geant4 (CERN, ~2000) Motivation –move away from hard-coded geometry (C++) –enable geometry interchange between applications Presently part of the CERN Simulation Framework (Simulation Project) as Geometry interchange format –Actively used at CERN for Physics comparisons (Geant4 - FLUKA) Geometry model exchange (Geant4 - ROOT)

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov GDML schema and I/O GDML is defined through XML Schema (XSD) defines document structure and the list of legal elements (position, rotation, material, solid,…) XSD are in XML -> they are extensible GDML I/O –C++ implementation of GDML processor Input Xerces-C SAX parser  'in-memory' representation of the geometry description Output Writing-out GDML data –Alternative Python-based processor uses xml.sax Python module allows very light binding to applications GDML Schema GDML file user application (1) GDML writer GDML reader user application (2)

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov GDML example Similar to HTML, explicit tags for elements, … ASCII file: easy to create, read, debug, modify,… positions, rotations materials solids geometry tree 'world' volume

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov GDML Status Solids supported: –box, sphere (G4Sphere and G4Orb), tube, cone, polycone, parallepiped, trapezoid (G4Trap and G4Trd), torus, polyhedron, hype (tube with hyperbolic profile), elliptical tube –Tetrahedron, tessellated, ellipsoid, twisted solids  NEW Boolean solids: –Union, subtraction, intersection Assembly of volumes Replicas and divisions Parameterized volumes –Position, rotation and size Loops, modular models  NEW –E.g. space electronic components,… Open source, collaborative development – Stable, mature Main G4 geometry format at ESA Antropomorphic Phantom, INFN, Giorgio Guerrieri, Maria Grazia Pia, Susanna Guatelli ConeXpress, ESA, Ronnie Lindberg LHCB, CERN, R.Maunder

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov Geant4 CAD interface Prototype by ESA REAT_MS contract (QinetiQ+sub.) –Uses G4TessellatedSolid (P.Truscott) –Requires auxiliary files created with ST- Viewer commercial S/W –Based on GDML (v 2.8) CAD-GDML interfaces in engineering tools ESABASE2 (eta_max) FASTRAD (TRAD) Future contract to integrate GEANT4 in CAD GUI framework CAD model STEP model GDML ST-Viewer StepTools Geant4 External CAD tool CAD tool OpenCascade library 10 GeV proton in wood LHEP_BIC_HP ESABASE 2 FASTRAD

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov ConeXpress model: R.Lindberg, ESA Sector Shielding Analysis Tool SSAT DOSE Estimate of the dose at a point –Based on external Dose-Depth curve E.g. SHIELDOSE-2 curve [rad VS g/cm 2 ] –Ray-by-ray dose calculation Results: –Total dose –Dose-Depth profile –Dose directionality Ray tracing: from a user-defined point within a Geant4 geometry NORM, SLANT and MIXED tracing SHIELDING shielding levels fraction of solid angle for which the shielding is within a defined interval global and from single materials shielding distribution the mean shielding level as a function of look direction It utilizes geantinos

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov MULASSIS and GEMAT Layer Geometry Physics list choice Analysis options –Dose –Pulse Height Spectrum –Ion. dose –NIEL –Dose Equivalent Primary particle spectrum and fluences from SPENVIS –Trapped protons –Solar protons –Trapped electrons –… Web interface Geant4-based Microdosimetry Tool Microdosimetry in geometries representing features of a semiconductor device (transistor/junction geometries) Analysis includes –single event effects (SEE) –simultaneous energy deposition in several sensitive regions (MBU)

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov GRAS Geant4 Radiation Analysis for Space Detector / Component effects –Dose, Fluence, NIEL, LET… for support to engineering and scientific design Human dosimetry –Dose Equivalent, Equivalent Dose,… for ESA exploration initiative 3D geometry –GDML format, or existing C++ class, … Ready-To-Use tool –Different analyses set without re-compilation Modular / extendable design Is being integrated into SPENVIS Santin et al, IEEE Trans. Nucl. Sci. 52, 2005

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov GRAS components RADIATION ENVIRONMENT /gps/pos/type Surface /gps/pos/shape Sphere... /gps/ang/type cos /gps/particle e Source - GDML - Used also for STEP CAD models Also provided: - MULASSIS – like - Interface to ESABASE (in progress) - C++ model /gras/geometry/type gdml /gdml/file geometry/conexpress.gdml Geometry 1 /gras/phys/addPhysics em_standard /gras/phys/addPhysics binary /gras/phys/addPhysics binary_ion /gras/phys/addPhysics lowe_neutron /gras/physics/setCuts 0.1 mm /gras/physics/stepMax 0.01 mm Geant4 physics models through script commands Physics 3 GEAN T4 Anal ysis Man ager D os e A na ly si s M od ul es D os e A na ly si s M od ul es D os e A na ly si s M od ul es D os e A na ly si s M od ul es D os e A na ly si s M od ul es Fl ue nc e A na ly si s M od ul es D os e A na ly si s M od ul es D os e A na ly si s M od ul es NI E L A na ly si s M od ul es D os e A na ly si s M od ul es D os e A na ly si s M od ul es … A na ly si s M od ul es /gras/analysis/dose/addModule doseB12 /gras/analysis/dose/doseB12/addVolume b1 /gras/analysis/dose/doseB12/addVolume b2 /gras/analysis/dose/doseB12/setUnit rad 4 Analysis In progress: Activation more SEE - NIEL - Fluence - Charging - LET - Path-length - Dose (TID) - Dose equivalent - Equivalent dose - Source monitoring - Detector analysis Santin et al, RADECS, 2005

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov GRAS Shielding assessment Comparison to ray-tracing Comparison of transmission (p, e-) Parametric study: stability of Geant4 dose estimates after transmission VS tracking parameters Dose comparison in simple and realistic satellite geometries Lindberg et al, accepted, IEEE Trans. Nucl. Sci.

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov GRAS Status and plans Current release V1.3 –Using Geant4 8.0.p01, GDML 2.5 Ongoing studies using GRAS –SREM radiation monitor (calibration) –HERSCHEL (glitch studies) –ConeXpress (dosimetry) –GAIA (dosimetry, transients) –RF filters (surface effects) Upgrades –New analysis modules –Review of uncertainties  to Geant4 release –Interface to PHITS (T. Koi) –Upgrade of physics list Coming release V1.4 –Using Geant4 8.1.p01, GDML 2.8 –Next weeks –Software Installation & User Manual  NEW JWST NIRSpec Neutron production TOF HERSCHEL Glitch study

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov Planetary exploration Robotic and human missions Long interplanetary journey Long permanence with scarce natural shielding New user requirements include: planetary models e.g. scaling of SPE fluence to other planets, magnetic field description, crustal maps ion physics electromagnetics / hadronics for HZE biological effects macroscopic / microscopic models very low energy physics

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov Geant4 DNA Damage mechanisms Interactions of Radiation with Biological Systems at the Cellular and DNA Level Geant4 extension to simulate electromagnetic interactions in liquid water down to ~7.5 eV –e -, p, H, He Processes for cell survival Human phantom library Applications in radiation protection, therapy protocol studies Analytical model INFN Genova

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov GEANT4 GEOMETRY  ISS configuration 14A, 400 volumes  Columbus, 800 volumes  Model available for collaborations from Tore Ersmark (KTH) CALCULATED DOSE RATES INSIDE COLUMBUS  Trapped protons: 2.0  Gy/h SPENVIS, AP8-min  GCR protons: 3.3  Gy/h CREME96, solar minimum Example spectra of penetrating trapped protons and secondary particles. Courtesy: T. Ersmark, KTH Stockholm The DESIRE project is funded by ESA (15613/NL/LvH) and the Swedish National Space Board. DESIRE DESIRE (cont) DESIRE Dose Estimation by Simulation of the ISS Radiation Environment

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov REMSIM Simulation and Analysis of Vehicle Concepts and Surface Habitat Designs Quantitative dosimetry Evaluation of interplanetary transfer vehicle concepts and habitat Interplanetary space radiation environment See S.Guatelli’s talk at this workshop

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov IEEE Trans Nucl Sci 52, No. 6, Dec 2005

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov PLANETOCOSMICS Interactions of cosmic rays with planets –Mars, Mercury, Earth Propagation in magnetosphere Interactions with atmosphere and soil Flux of shower particles in atmosphere and soil (new) Energy deposited in atmosphere and soil (new) In development –Jupiter case Available at Laurent Desorgher Space IT and Uni. Bern

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov Active Shielding MarsREM project Literature review on active magnetic shielding Development of a G4 magnetic shielding tool for computing shielding of space radiation by artificial magnetic fields Comparative study of active and passive shielding by using this tool In progress – release end 2007 Laurent Desorgher Space IT and Uni. Bern

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov Tools for the Space Users’ community Geant4 Space Users’ web page –Users –~100 publications –News Feedback appreciated

Giovanni Santin - Recent ESA-related developments - Pasadena, Nov To do