1. Distributed Geant4 simulations on NorduGrid Andi Hektor andi.hektor@cern.ch NICPB in Tallinn (CERN, Estonian Grid) 2 nd Geant4 Workshop at HIP June 6-7, 2005

2. Outline The problem: mobile gamma-ray spectrometry The detector system and detection limits Geant4 model and some examples Distributed MC simulations on the Grid Some results, conclusions and questions

3. A. Hektor, K. Kurvinen, R. Pöllänen and P. Smolander Radiation and Nuclear Safety Authority (STUK) M. Kettunen Finnish Defence Forces Technical Research Centre J. Lyytinen Helsinki University of Technology, Laboratory of Lightweight Structures Funded by: SCIENTIFIC ADVISORY BOARD FOR DEFENCE REAL TIME RADIATION SURVEILLANCE EQUIPMENT FOR THE UNMANNED AERIAL VEHICLE RANGER In the frames of the project:

4. Mobile gamma-ray detector Tracking of a release plume Time critical, decision aid for initial response, radiation safety of the air crew Fallout mapping After the initial emergency, long term risk management Locating of a point source Lost sources, smuggling and terrorism Unmanned aerial vehicle (UAV) is an excellent choice!

5. Unmanned aerial vehicle Ranger Tactical UAV Operated by FDF Range: 150 km Endurance: 5 hrs Payload: 40 kg Catapult take-off Landing on skids Fully autonomous or remotely piloted

6. Geometry of the detector system Airworthiness above all Vibration attenuation Temperature control Modularity Easy installation Light weight structure

7. Installation of the detector

8. The gamma-ray spectrometer

9. Physics in a gamma-ray scintillator NaI(Tl) Photoelectric absorption Compton scattering Pair production Multiple scattering Electron ionisation Bremsstrahlung Positron annihilation Source

10. Detection limits of the detector Different type of sources, long distances between the source and detector, high speed of the detector, energy resolution 1D 3D 2D

11. Constructing of our detector model in Geant4 Geometry Physics List Input parameters Kernel Analysis Visualization Visualization files Histograms Kernel logsTracks CAD model Analysis Ideas for physics and input data

12. Some examples of our MC simulations in Geant4 (1/4) Energy of the gammas: 662 keV (Cs-137) Number of the gammas: 15 Example 1 Example 2

13. Some examples of the MC simulations in Geant4 (2/4) Energy of the gammas: 662 keV (Cs-137) Number of the gammas: 15 Example 2

14. Some examples of the MC simulations in Geant4 (3/4) Energy of the gammas: 662 keV (Cs-137) Number of the gammas: 15 Example 4

15. Some examples of the MC simulations in Geant4 (4/4) Energy of the gammas: 662 keV (Cs-137) Number of the gammas: 15 Example 4

17. Distributed MC simulations Input Output    Parallel comutings on the different comuters

18. The Grid Users  Computing Resources Data Storage Elements Special Devices Cert. Authority (PKI) Information System

19. NorduGrid

20. Estonian Grid, Jan 2004 GIIS First “PC-cluster” Certification Authority Phone of the local Registration Authority

21. Management of the “gridified” Gean4 simulations Generator of Grid jobs ( simple Perl script ) Simple job manager (Python script + MySQL) Data collector ( simple Perl script ) Data analysis tools ( ROOT scripts ) Geant4 macro files Resource Specification files ROOT data files The Grid Compiled ROOT data file Management Politics Logs

22. Our Grid jobs Compiled binary of the Geant4 code (3.7 MB): Linux, glibc 2.6.9 Geant4 macro file with input parameters: /gun/energy 662 keV /run/beamOn 500000000, etc In total 640 Grid jobs were submitted Computation time in total: 417 CPU days

23. Statistics of the Grid jobs 640 jobs and 2.6 GB of data Computation time in total: 417 CPU days (on 2.4 GHz and 3.06 GHz Intel P4) 17 failed jobs (2.6%) during the computations and 16 post-processing errors (2.5%) NorduGrid middleware is surprisingly stable!

25. Some conclusions and open questions It is easy to “gridify” Geant4 applications NorduGrid middleware is stable enough Is it possible to add “Grid functionality” to the Geant4 package? Other middleware packages: LCG2, gLite, UNICORE etc

26. Thank you and… STUK and HIP in Helsinki STUK and HIP in Helsinki SCIENTIFIC ADVISORY BOARD FOR DEFENCE IN FINLAND for funding the initial work SCIENTIFIC ADVISORY BOARD FOR DEFENCE IN FINLAND for funding the initial work Other members of technical coordination group of the Estonian Grid: Mario Kadastik (NICPB), Lauri Anton, Hardi Teder (EENet), Konstantin Skaburskas (UT) Other members of technical coordination group of the Estonian Grid: Mario Kadastik (NICPB), Lauri Anton, Hardi Teder (EENet), Konstantin Skaburskas (UT) NorduGrid core developers for technical support NorduGrid core developers for technical support Estonian Science Foundation: the grants no. 5135, 5935, 5316 Estonian Science Foundation: the grants no. 5135, 5935, 5316 EU 6th FP: the grant EC MC MERG-CT-2003-503626 EU 6th FP: the grant EC MC MERG-CT-2003-503626 Ministry of Education and Research of Estonia: the support of the technical meetings of the Estonian Grid Ministry of Education and Research of Estonia: the support of the technical meetings of the Estonian Grid