simulation of x-ray fluorescence and application to planetary astrophysics a. mantero, m. bavdaz, a....
TRANSCRIPT
Simulation of X-ray Simulation of X-ray Fluorescence and Fluorescence and
Application to Planetary Application to Planetary AstrophysicsAstrophysics
A. Mantero, M. Bavdaz, A. Owens, A. Peacock, M. G. PiaA. Mantero, M. Bavdaz, A. Owens, A. Peacock, M. G. Pia
IEEE NSS -- Portland, Thursday, Oct 23, 2003
IEEE NSS -- Portland, Thursday, Oct 23, 2003
The BepiColombo Mission to MercuryThe BepiColombo Mission to Mercury
Composed of 3 spacecrafts: 2 orbiters and a lander carrying 25 scientific experiments.
● Magnetic Field Study● Planet Surface Mapping● Planet Surface Composition study
● 4 spectrometer (IR, X, , n)
● 1 laser altimeter
●1 lander (X-Ray Spectrometer, Imaging Camera, Seismometer)
HERMESIs an X-Ray spectrometer to
measure the composition of the upper layers of planetary surface
Basalt fluorescence spectrum
Beam Energy 9.5 KeV
Cou
nts
Energy (KeV)
IEEE NSS -- Portland, Thursday, Oct 23, 2003
Basalt fluorescence spectrumBeam Energy 9.5 KeV
Cou
nts
Energy (KeV)
IEEE NSS -- Portland, Thursday, Oct 23, 2003
Fluorescence Fluorescence SimulationSimulation
● Space missions are risky, so solid strategies for risk mitigation are to be undertaken
● Preparing a correct and detailed simulation is a crucial part of these strategies
● HERMES is an X-Ray spectrometer studying Mercury's surface composition
● Space missions are risky, so solid strategies for risk mitigation are to be undertaken
● Preparing a correct and detailed simulation is a crucial part of these strategies
● HERMES is an X-Ray spectrometer studying Mercury's surface composition
We need to simulate X-Ray fluorescence We need to simulate X-Ray fluorescence (1-10 KeV) (1-10 KeV) from Mercury surface produced by solar radiationfrom Mercury surface produced by solar radiation
IEEE NSS -- Portland, Thursday, Oct 23, 2003
GeantGeant44
● “A toolkit for the simulation of the passage of particles through matter”● Object-Oriented technology● Developed following ISO 15504 software process implementing iterative-incremental model
● Low energy electromagnetic processes extensions until 100 eV● Advanced instruments for the description of geometry and materials
Geant3 10 KeV
EGS4 1 KeV
IEEE NSS -- Portland, Thursday, Oct 23, 2003
The Atomic Deexcitation The Atomic Deexcitation PackagePackage
Unique interface to be used by any process
Modularity permits a better management and easiness of expansion (Auger)
Fluorescence and Auger emissions are simulated using data present on the EADL (Evaluated Atomic Deexcitation Library) from Livermore
Fluorescence and Auger emissions are simulated using data present on the EADL (Evaluated Atomic Deexcitation Library) from Livermore
The package has undergone both The package has undergone both software and physical validationsoftware and physical validation
IEEE NSS -- Portland, Thursday, Oct 23, 2003
ValidationValidation
● Software Validation● Software Validation
● System Tests● System Tests
● Integration Tests● Integration Tests
● Unit Tests● Unit Tests
● Physical Validation● Physical Validation● Auger● Auger
● Fluorescence ● Fluorescence
IEEE NSS -- Portland, Thursday, Oct 23, 2003
Physical Validation - Physical Validation - AugerAuger
Simulation of Auger emission from pure materials irradiated by an electron beam with continuous ramp spectrum.
Simulation of Auger emission from pure materials irradiated by an electron beam with continuous ramp spectrum.
Comparison between energy of simulated
outflowing electrons and data found in literature
Percent Error: Percent Error: 0.74 % 0.74 % ± 0.07± 0.07
Full comparison with experimental data from rocks X-Ray irradiation
(Bessy)
Full comparison with experimental data from rocks X-Ray irradiation
(Bessy)
Iceland Basalt Fluorescence Spectrum
Cou
nts
Energy (keV)
IEEE NSS -- Portland, Thursday, Oct 23, 2003
Physical Validation - Physical Validation - FluorescenceFluorescence
Parametric analysis of data
Pure ElementsComplex Materials
Many Peaks
Physical Background
Many Peaks
Physical Background
Anderson-Darling● Goodness of Fit test
● Doesn't depend upon data grouping
● No symmetry needed
● No cut on data number
Look B. MascialinoData Analysis in HEP: A Statistical Toolkit2003 NNS, Portland, Oregon, USA
IEEE NSS -- Portland, Thursday, Oct 23, 2003
Physical Validation - Physical Validation - FluorescenceFluorescence
Preliminar analysis Pearson correlation:
r>0.93 p<0.0001
High Statistical correlation
Ac (95%) =0.752
Anderson Darling resultsBeam Energy
4.96.58.29.5
Experimental and simulated X-Ray Spectra
are statistically compatible at a 95% C.L.
Experimental and simulated X-Ray Spectra
are statistically compatible at a 95% C.L.
A20.040.010.210.41
SimulatedExperimental
IEEE NSS -- Portland, Thursday, Oct 23, 2003
Application – DIANEApplication – DIANEData for
comparison have been taken during a
test beam at BESSY
laboratories.
A GEANT4 application has been created reproducing:● Experimental set-up● Materials ● Detectors
A GEANT4 application has been created reproducing:● Experimental set-up● Materials ● Detectors
The application is CPU consuming, so it has been
interfaced to the GRID thanks to the DIANE
framework
Execution Times are reduced of an order of
magnitude
(750 Mevents -> 24 Hours)
Execution Times are reduced of an order of
magnitude
(750 Mevents -> 24 Hours)
talk: DIANE -- Distributed Analysis Environment for GRID-enabled Simulation and Analysis of Physics Data (Friday 24th October)
The experimental set-up at the PTB laboratory at BESSY-II. The XRF chamber can be seen to be attached to the end of the Four Crystal Monochromator (FCM) beamline.
Si
GaAs
FCM beamline
Si reference
XRF chamber
IEEE NSS -- Portland, Thursday, Oct 23, 2003
Work In ProgressWork In ProgressOptimization phase...
Bepicolombo application:
● New Geometries● Runtime Analysis Features (AIDA/ANAPHE)
IEEE NSS -- Portland, Thursday, Oct 23, 2003
ConclusionsConclusionsFull atomic
deexcitation validationPredictive capability of deexcitation processes
Use of Geant4 applications for Physic Reach studies and experimental set-up optimization
Physic validation Geological material DetectorGeometry