1. Sector Shielding analysis tool (SSAT) Computation Automation Using UNIX Awk and MSC/NASTRAN FEM model EFACEC - October 3-7 2005 Adolfo Aguilar

2. 2SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October Overview  Objective: –Optimized Mass for the Electronics unit –TID and Aluminium Shielding Map for PCBs –Internal radiative environment definition for the equipment –Selection of appropriate electronics for the unit –Engineering approach to reduce analysis costs  Approach –Use of programming scripts to translate from FEM information to GEANT4 analysis –SPENVIS SHIELDOSE-2 - GEANT4 SSAT computation

3. 3SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October HARDWARE UNDER STUDY  Components Technology Test Bed (CTTB)  Two Units –Control Unit –Experiment Board (EB) Pallet  Limited Mass budget  EB Pallet located outside S/C  Mass optimization required

4. 4SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October ORBIT DEFINITION  Orbit Location Mission 1 GSTB-IOV Orbit type: Walker 27/3/1+3 Apogee: 23616.00 km Perigee: 23616.00 km Inclination: 56.00º R.A. Ascending Node: 120.00º Argument of Perigee: 0.00º Period: 14.36 hrs Duration: 0.60 days Number of orbits: 1.0 Orbit start: 01/01/2006 00:00: 0.0 Orbit end: 01/01/2006 14:21:18.4 Mission end: 31/12/2010 00:00: 0.0 Mission length: 1825.00 days (5.00 years)

5. 5SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October GALILEO-IOV S/C  EB PALLET LOCATED OUSIDE S/C

6. 6SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October RADIATION ENVIRONMENT  SPENVIS SHIELDOSE-2 (Al-spheres) Analysis based on GALILEO orbit too pessimistic  6 mm Al thickness for the desired TID on PCBs (50krad)

7. 7SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October GEANT4 DRAWBACKS  Physicist Oriented Tool –Lack of physical models explanation –Lack of definition of applicability limits  Very time consuming tool –Geometry definition demands a lot of workload –Output Results not directly applicable for engineering use Too theoretical/ideal results Not directly applicable to front-end electronics simulation Lot of post-process required to be cost-effective

8. 8SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October FEM Model A source of Analysis Points A translation from FEM to GEANT4 is possible Each node in the FEM mode is the location of a target point for the analysis

9. 9SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October SECTORIAL ANALYSIS (GEANT4-SSAT) GEANT4 model for S/C and EB Pallet

10. 10SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October UNIX tools to translate FEM into GEANT4  FEM models are ASCII based files  Node and connectivity definition is defined  Material and geometrical definition already coded  AWK, Perl, Phyton process can automate the task  Output results can be plotted using FEM postprocessors –PATRAN –IDEAS

11. 11SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October Sectorial Analysis for the PCBs  FEM Grids used as point target for the analysis  Shielding and TID map for each PCB  Very Fast and Efficient Method –From Geometry definition to post-process 3 days

12. 12SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October Post-Processed Results using PATRAN  TID Maps obtained for each location of the PCB  3.5 mm (30krad) Al thickness reduced the mass

13. 13SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October Conclussions  GEANT4 needs a more engineering approach to be a cost effective tool for electronics/detectors design tool  Existing tools for FEM analysis can be used to optimize the analysis time  UNIX tools like AWK, Perl or Phyton can be used to translate FEM models information into GEANT4 analysis cases  Post-Process can be done using existing tools from the market like PATRAN or IDEAS.  A better understanding of the GEANT4 physical models is demanded with proper explanation of the applicability limits for better engineering use.