Distributed Geant4 simulations on NorduGrid

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Distributed Geant4 simulations on NorduGrid

• Andi Hektor
• andi.hektor_at_cern.ch
• NICPB in Tallinn
• (CERN, Estonian Grid)

2nd Geant4 Workshop at HIP June 6-7, 2005
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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

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In the frames of the project
REAL TIME RADIATION SURVEILLANCE EQUIPMENT FOR
THE UNMANNED AERIAL VEHICLE RANGER
Funded by SCIENTIFIC ADVISORY BOARD FOR DEFENCE
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
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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!
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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

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Geometry of the detector system
Light weight structure

• Airworthiness above all
• Vibration attenuation
• Temperature control
• Modularity
• Easy installation

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Installation of the detector
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The gamma-ray spectrometer
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Physics in a gamma-ray scintillator

• Photoelectric absorption
• Compton scattering
• Pair production
• Multiple scattering
• Electron ionisation
• Bremsstrahlung
• Positron annihilation

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Detection limits of the detector
3D
1D
2D
Different type of sources, long distances between
the source and detector, high speed of the
detector, energy resolution
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Constructing of our detector model in Geant4
Ideas for physics and input data
CAD model
Physics List
Geometry
Input parameters
Kernel
Analysis
Visualization
Histograms
Visualization files
Kernel logs
Tracks
Analysis
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Some examples of our MC simulations in Geant4
(1/4)
Example 1
Example 2
Energy of the gammas 662 keV (Cs-137) Number of
the gammas 15
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Some examples of the MC simulations in Geant4
(2/4)
Example 2
Energy of the gammas 662 keV (Cs-137) Number of
the gammas 15
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Some examples of the MC simulations in Geant4
(3/4)
Example 4
Energy of the gammas 662 keV (Cs-137) Number of
the gammas 15
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Some examples of the MC simulations in Geant4
(4/4)
Example 4
Energy of the gammas 662 keV (Cs-137) Number of
the gammas 15
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Distributed MC simulations
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Input
Output
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Parallel comutings on the different comuters
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The Grid
Cert. Authority (PKI)
Special Devices
Information System
Data Storage Elements
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Users
Computing Resources
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NorduGrid
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Estonian Grid, Jan 2004
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Management of the gridified Gean4 simulations
Generator of Grid jobs (simple Perl script)
Geant4 macro files Resource Specification files
Management Politics
Simple job manager (Python script MySQL)
The Grid
ROOT data files
Logs
Data collector (simple Perl script)
Compiled ROOT data file
Data analysis tools (ROOT scripts)
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Our Grid jobs

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

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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!
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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

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Thank you and

• STUK and HIP in Helsinki
• 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)
• NorduGrid core developers for technical support
• Estonian Science Foundation the grants no. 5135,
  5935, 5316
• 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