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GAMOS an easy and flexible framework for GEANT4 simulations Pedro Arce Juan Ignacio Lagares

GAMOS an easy and flexible framework for GEANT4 simulations Pedro Arce Juan Ignacio Lagares Pedro Rato Mendes Mario Cañadas (CIEMAT) CIEMAT, Madrid, 18 May 2009. Outline. Analysis and optimisation Control histograms Verbosity Optimisation Applications PET Radiotherapy Accelerator

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GAMOS an easy and flexible framework for GEANT4 simulations Pedro Arce Juan Ignacio Lagares

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  1. GAMOS an easy and flexible framework for GEANT4 simulations Pedro Arce Juan Ignacio Lagares Pedro Rato Mendes Mario Cañadas (CIEMAT) CIEMAT, Madrid, 18 May 2009

  2. Outline • Analysis and optimisation • Control histograms • Verbosity • Optimisation • Applications • PET • Radiotherapy • Accelerator • Dose in phantom • Analysis • Optimisation • Documentation • Installation • Release and user support • Usage • Introduction • GEANT4-based frameworks • GAMOS objectives • GAMOS plug-in’s • GAMOS history • GAMOS functionality • Geometry • Movements • Primary generator • Physics • User actions • Sensitive detector and hits • Histogramming • Parameter management • Scoring

  3. Introduction

  4. GEANT4-based frameworks • GEANT4 is a very powerful and flexible toolkit • But: it is not easy for a beginner • Everything requires writing C++, and a good knowledge of GEANT4 details • No complete set of tools for an application • Several frameworks try to make GEANT4 easy to use in a specific domain: • Providing an scripting language, so that no C++ is needed • Trying to cover with it all the user requirements in the field • But a common problem of these frameworks is that the user sooner or later wants to do something not foreseen by the framework • Understand how the framework works and modify it (difficult and risky) • Do it by her/himself, without the framework • SOLUTION: plug-in based framework • Any new component can be inserted (plugged) in the framework without touching it or knowing its details, and then used as a command • + good modularity and documentation

  5. GAMOS objectives The first objective of GAMOS is to allow the user to: • Simulate fully a medical physics project with a minimal knowledge of GEANT4 and no need of C++ (only text scripts) • Already operative for PET and radiotherapy The second objective is to allow the user to: • Easilyadd new functionality and combine it with the existing functionality in GAMOS • And also reuse any GEANT4 C++ code (from the user, from GEANT4 examples, …) • Transform C++ code into user commands in a very simple way The third objective is to provide a comprehensive set of tools: to extract the required information and optimize an application • Flexible user actions + filters & classifiers • Powerful scoring framework • Utilities to optimize CPU in a simple way

  6. GAMOS plug-in´s • Most users will be able to do their simulation with simple user commands • If they want to have something not foreseen by the framework  use plug-in’s • GAMOS has no predefined components • At run-time user selects which components to load through user commands • They are loaded through the plug-in mechanism • User has full freedom in choosing components • User can define a component not foreseen by GAMOS • Take a C++ class and use it through an user command • Mix it with any other component For example: instead of GAMOS generator use the one from G4 example underground_physics DEFINE_GAMOS_GENERATOR(DMXPrimaryGeneratorAction); and then you can select it in your script /gamos/generator DMXPrimaryGeneratorAction For the plug-in's implementation in GAMOS it has been chosen the CERN library: SEAL

  7. GAMOS history GAMOS started as a framework beginning 2007 • to help in the simulation of CIEMAT PET detector projects • it was after extended for radiotherapy applications GATE was considered and rejected because it was too rigid: not possible to simulate the projects at CIEMAT • Compton-PET detector • BrainPET (optical photons) • Pixel-PET (trapezoidal detectors, different hit logic) GAMOS is the fruit of several years experience developing Geant4-based frameworks • Member of Geant4 since 1998 • Coordination of the CMS Geant4 framework during its first years • The first LHC Geant4 framework to be fully operative • Coordination the HARP (PS) Geant4 framework (by nomination from S.Giani, first Geant4 spokeman) CIEMAT group had several years experience with PET detectors and radiotherapy

  8. Functionality

  9. Geometry Three different ways to define it: C++ code: • The usual GEANT4 way • Add one line to transform your class in a plug-in DEFINE_GAMOS_GEOMETRY (MyGeometry); so that you can select it in your input macro /gamos/geometry MyGeometry Define it in ASCII (text) files • The easiest way to define a geometry • Based on simple tags • Same order of parameters as corresponding GEANT4 classes Using one of the GAMOS examples for simple cases • Simple PET can be defined through an 8-parameters file (n_crystals, crystal_x/y/z, radius, …) • Simple phantoms with a few user commands

  10. Geometry from text files • Based on simple tags, with same order of parameters as corresponding GEANT4 classes :MATE Cu 29 63.54 8.9333*g/cm3 :VOLU yoke TUBE  62.*cm 820. 1.27*m Cu :ROTM RM0 0. 0. 0. :PLACE  yoke  1   expHall  RM0   0.   0.   370.*cm MATERIALS: • Isotopes • Elements • Simple materials • Material mixtures by weight, volume or number of atoms • GEANT4 intrinsic materials • + 300 predefined materials common in medical field SOLIDS: • All GEANT4 “CSG” and “specific” solids • Twisted solids • Tesellated solids • Boolean solids ROTATIONMATRICES: • 3 rotation angles around X,Y,Z • 6 theta and phi angles of X,Y,Z axis • 9 matrix values

  11. Geometry from text files PLACEMENTS: • Simple placements • Divisions • Replicas • Parameterisations • Linear, circular or square • For complicated parameterisations example of how to mix the C++ parameterisation with the ASCII geometry file COLOUR VISUALISATION ON/OFF PARAMETERS: • Can be defined to use them later :P InnerR 12. :VOLU yoke :TUBS  Iron   3  $InnerR 820. 1270. ARITHMETIC EXPRESSIONS: • Elaborated expressions can be used :SOLID yoke TUBE sin($ANGX)*2+4*exp(1.5) 820. 1270. UNITS: • Default units for each parameter • Each value can be overridden by user

  12. Geometry from text files INCLUDE OTHER FILES (hierarchical approach): #include mygeom2.txt. User can extend it: add new tags and process it without touching base code Can mix a C++ geometry with a text geometry GEANT4 in memory geometry  text files Install and use it as another GEANT4 library G4VPhysicalVolume* MyDetectorConstruction::Construct(){ G4tgbVolumeMgr* volmgr = G4tgbVolumeMgr::GetInstance(); volmgr->AddTextFile(filename); // SEVERAL FILES CAN BE ADDED return = volmgr->ReadAndConstructDetector(); HISTORY: • In use to build GEANT4 geometries since 10 years ago • An evolving code… • It is part of the GEANT4 release since December ‘08 :ROTM R00 0. 0. 0.:VOLU world BOX 100. 100. 100. G4_AIR:VIS world OFF:VOLU "my tube" TUBE 0. 10. 20. G4_WATER:P POSX 5 :PLACE "my tube" 1 world R00 0. 0. -$POSX:VOLU sphere ORB 5. G4_Si :PLACE sphere 1 "my tube" R00 0. 1. $POSX

  13. Movements User can move a volume by using commands • Displacements or rotations • Every N events or every interval of time • N times or forever • Offset can be defined • Several movements of the same volume or different ones can be set

  14. Generator • C++ code • The usual GEANT4 way • Add one line to transform your class in a plug-in • DEFINE_GAMOS_GENERATOR(MyGenerator); • so that you can select it in your input macro • /gamos/generator MyGenerator • GAMOS generator • Combine any number of single particles or isotopes decaying to e+, e-, g • For each particle or isotope user may select by user commands any combination of time, energy, position and direction distributions • Or create its own and select it by a user command (transforming it into a plug-in) /gamos/generator/directionDist source GmGenerPositionDiscGaussian 1.*mm /gamos/generator/timeDist source GmGenerTimeDecay

  15. Generator distributions • POSITION: • Point Square Rectangle • Disc DiscGaussian LineSteps • InG4Volumes (sphere/box/tube_section/ellipsoid) • InG4VolumeSurfaces (sphere/box/tube_section/ellipsoid) • InG4VolumesGeneral (any solid) VoxelPhantomMaterials • DIRECTION: • Random Const Cone • ENERGY: • Constant Gaussian RandomFlat • BetaDecay ConstantIsotopeDecay • TIME: • Constant Decay • POSITION & DIRECTION: • InVolumeSurfaceTowardsCentre TowardsBox • A template provided for each type: users only have to write a few C++ lines to create their own distribution F18 decay

  16. Physics • C++ code • The usual GEANT4 way • Add one line to transform your class in a plug-in • DEFINE_GAMOS_PHYSICS_LIST (ExN02PhysicsList); • so that you can select it in your input macro • /gamos/physicsList ExN02PhysicsList • Any GEANT4 physics list can be easily selected through a user command • GAMOS physics list • Based on hadrotherapy advanced example • User can combine different physics lists for photons, electrons, positrons, muons, protons and ions • A dummy one for visualisation

  17. User actions • They are the main way for a user to extract information of what is happening and modify the running conditions: flexible framework is needed • User can have as many user actions of any type as desired • Only 1 of each type in GEANT4 • One user action can be of several types (run/event/stacking/tracking/stepping) • Only 1 class - 1 type in GEANT4 • User actions can use filters and classifiers /gamos/userAction GmTrackHistosUA GmGammaFilter • User can activate any user action by a user command • User can create new user actions • Just adding a line to transform it into a plug-in DEFINE_GAMOS_USER_ACTION(MyUserAction); that can be selected with a user command /gamos/userAction MyUserAction

  18. Sensitive Detectors • To produce hits in GEANT4 a user has to (with C++): • Define a class inheriting from G4VSensitiveDetector • Associate it to a G4LogicalVolume • Create hits in the ProcessHits method • Clean the hits at EndOfEvent • In GAMOS you can do all this with a user command • /gamos/assocSD2LogVol SD_CLASS SD_TYPE LOGVOL_NAME • SD_CLASS: the G4VSensitiveDetector class • SD_TYPE: an identifier string, so that different SD/hits can have different treatment • Users can create her/his own SD class and make it a plug-in • DEFINE_GAMOS_SENSDET(MySD);

  19. Hits Bi fluorescence peak 511 keV photoelectric (PE) peak backscattering peak escape peak E > 511 keV photoelectric peaks • A GAMOS hit has the following information: • ID of the sensitive volume copy • event ID • energy • time of the first E deposit • time of the last E deposit • position • list of all tracks that contributed • list of all ‘primary´tracks that contributed • list of all deposited energies • SD type • Users can create his/her own hit class • Hits can be stored in a job and read in another job • Format compatible with STIR software (PET reconstruction) /gamos/userAction GmHitsHistosUA

  20. Detector effects • Measuring time • - A detector is not able to separate signals from different events if they come close in time • Dead time • When a detector is triggered, this detector (or even the whole group it belongs to) is not able to take data during some time • Paralizable or non-paralizable • Both can be set by the user in the input macro • A different time for each SD_TYPE • /gamos/setParam SD:MeasuringTime:MySD_1 1000.*ns • /gamos/setParam SD:MeasuringTime:MySD_2 250.*ns

  21. Hits digitization and reconstruction • Framework to transform simulated hits digital signals reconstructed hits (energy/time/position) • Digitization and hits reconstruction are very detector specific : it is not possible to provide a general solution • GAMOS just provide a few simple digitizers and hits reconstructor s • 1 hit  1 digit • Merge hits close enough • Same set of sensitive volumes • Closer than a given distance • … and a basic structure • Hits compatible in time • spanning various events • Trigger • Pulse simulation • Sampling • Noise -- hits -- clusters of hits /gamos/userAction GmHitsHistosUA /gamos/userAction GmRecHitsHistosUA

  22. Histogramming • Own format: can write histograms in text files (CSV) without any external dependency • Read them in Excel, Matlab, Origin, GNUplot, … • Also ROOT histograms supported • AIDA will be supported soon /gamos/userAction GmGenerHistosUA /gamos/analysis/fileFormat CSV MS Excel graphics of energy of e+ from F18 decay

  23. Histogramming • Same code to create and fill histograms independent of the format • GAMOS takes care of writing the file in the chosen format at the end of job • Easy for a user to create a new one • GmAnalysisMgrkeeps a list of histograms so that they can be accessed from any part of the code, by number or name • GmAnalysisMgr::GetInstance(“pet”)->GetHisto1(1234)->Fill(ener); • GmAnalysisMgr::GetInstance(“pet”)->GetHisto1(“CalorSD: hits energy”)->Fill(ener); • There can be several files, each one with its own histograms • When creating an histogram, user chooses file name • User can define a suffix name, so all histogram files of a job will have a unique identification • /gamos/setParam GmAnalysisMgr:FileNameSuffix testParam_1

  24. Parameter management • Many classes change their behaviour depending on the value of some parameters that the user can set • GAMOS utilities use parameters extensively to maximise the flexibility • Always a default value in case the user does not care • Parameters can be numbers, strings, list of numbers or list of strings • GAMOS provides a unique command to manage all these parameters • A parameter is defined in the input macro • /gamos/setParam SD:EnergyResol 0.1 • Any class can use this value in any part of the code • float enerResol = GmParameterMgr::GetInstance() • ->GetNumericValue(“SD:EnergyResol”,0.);

  25. Scoring • Scoring is an important part of your simulation  powerful and flexible framework developed: • Many possible quantities can be scored in one or several volumes • ● Dose ● Deposited energy ● Flux (in/out/passage) • ● Current (in/out/passage) ● Charge ● Step length • ● Number of particles ● Number of interactions ● Number of 2ary particles • ● Number of steps ● Minimum kinetic energy • For each scored quantity one or several filters can be used • Only electrons, only particles of a certain energy range, … • Several ways to classify the different scores • One different score for each different volume copy, or volume name, or energy bin, … • Results can be printed in one or several formats for each scored quantity • Standard output, text file, binary file, histograms • All scored quantities can be calculated with/without errors • All scored quantities can be calculated per event or per job • Taking into account correlations from particles from same event • Everything managed with user commands

  26. Analysis and Optimisation

  27. Analysis and optimisation • We have made a substantial effort to provide tools to help users in • Knowing all the details of what is happening in the simulation • Optimising GEANT4 for her/his application • Flexible user actions • Flexible and powerful scoring • Many control histograms • Detailed verbosity control • Detailed CPU time study • Profiling your simulation • Setting physics cuts by volumes through user commands • Automatic optimisation of cuts • Variance reduction techniques

  28. Control histograms • Many control histograms, available through user commands: • Track/step: initial energy, energy lost, energy deposited, number of steps, track length, step length, position, deviation • Secondaries (for each process type): number of secondaries, energy of secondaries, total energy lost, step length, energy of primary, angle deviation of primary, angle primary-secondary • Primary generator: energy, 1D and 2D positions, angles, time between events • Table of interactions: how many times each process type happened, how many times a particle was created by a process type • Hits (for each SD type): number of hits, energy, number of energy deposits, width, time span, distance between hits, positions (Cartesian, cylindrical) • Reconstructed hits (for each SD type): number of rechits, energy, number of hits, width, time span, distance between hits, positions (Cartesian, cylindrical) • Positron: initial energy, final energy, final time, final range, final distance to origin, gamma energies, gamma angles, range vs energy, range vs distance, … • PET: distance PET line to vertex, hit energies, positron gammas histos (to disentangle detector effects) • PET classification table: true/scatter/random coincidences/random&scatter, close or far from vertex, recovered Compton hits or not • Radiotherapy phase space: X, Y, XY, theta, phi, energy, Vx, Vy, Vz • Radiotherapy dose in phantoms: dose, dose-volume, PDD, profile, user selection of voxels

  29. Control histograms • Controlled by filters ● Start/End/Enter/Exit/Traverse/In LogicalVolume/PhysicalVolume/Touchable/Region (24 filters) ● Gamma ● Electron ● Positron ● Particle in list ● Energy in an interval ● Primary ● Secondary ● Step Number ● Inverse filter ● OR filter ● XOR filter ● Filter with history (pass filter in any previous track step) ● Filter with ancestor history (one ancestor pass filter in any previous track step) • and classifiers ● ByParticle ●ByKineticEnergy ● By1Ancestor ● ByNAncestors ● ByLogicalVolume ● ByPhysicalVolume ● ByTouchable ● ByRegion ● ByExtraInfoPhaseSpace • Filters and classifiers are plug-in’s: more can be easily added • +200 histograms & 23 scorers + 44 filters & 12 classifiers, all managed with simple user commands: vast amount of possibilities to extract required information • User actions/scorers/filters/classifiers are plug-in’s: easy to add a new one

  30. Verbosity • Verbosity controlled through user commands • Different verbosities for different simulation parts (geometry, physics, generator, PET, radiotherapy, …) • 6 levels of verbosity (silent, error, warning, info, debug, test) • Selectable by user commands /gamos/verbosity PETVerbosity debug • Verbosity managers are plug-ins: user can easily create its own one • GEANT4 tracking verbosity can be controlled by event and by track • some events very verbose, others not /gamos/setParam GmTrackingVerboseUA:EventMin 14632 /gamos/setParam GmTrackingVerboseUA:EventMin 14635 /gamos/setparam GmTrackingVerboseUA:TrackMin 1 /gamos/setparam GmTrackingVerboseUA:TrackMax 20

  31. Optimisation: time studies • User commands to get CPU time study • By particle, energy bins, volume, region (or combination of them) Just add a user command: /gamos/userAction GmTimeStudyUA GmClassifierByParticle GmClassifierByEnergy • gamma/0.001-0.01: User=0.01 Real=0 Sys=0 • gamma/0.01-0.1: User=2.01 Real=2.45 Sys=0.27 • gamma/0.1-1: User=19.12 Real=22.05 Sys=1.51 • gamma/1-10: User=4.25 Real=5.4 Sys=0.3 • e-/0.0001-0.001: User=0.07 Real=0.1 Sys=0 • e-/0.001-0.01: User=0.54 Real=0.69 Sys=0.06 • e-/0.01-0.1: User=4.71 Real=5.41 Sys=0.38 • e-/0.1-1: User=15.59 Real=18.19 Sys=1.79 • e-/1-10: User=82.83 Real=98.62 Sys=7.45 • Example to get detailed gprof profiling about where (in which methods) the time is spent • Time spent in a method and integrated time in all the methods called by it

  32. Optimisation: setting cuts • All GEANT4 commands are available, for example to control cuts and electromagnetic physics parameters • Cuts by region can be defined through user commands or in the TEXT geometry file • Automatic conversion energy cut  range cut Just add two user commands: /gamos/userAction GmCutsEnergy2RangeUA /gamos/ECuts2RangeCuts * 10.*keV gamma • MATERIAL: G4_AIR PART: gamma ENERGY CUT: 0.01 (MeV) = RANGE CUT: 17407.7 (mm) • MATERIAL: G4_Cu PART: gamma ENERGY CUT: 0.01 (MeV) = RANGE CUT: 0.185575 (mm) • MATERIAL: G4_W PART: gamma ENERGY CUT: 0.01 (MeV) = RANGE CUT: 0.0149411 (mm) User limits can be attached to one/several logical volume(s) through user commands • MaxStep, MaxTrkLength, MaxTOF, MinKinE, MinRange • Automatic determination of best cuts and user limits in one job • Method based on tagging particles instead of killing them

  33. Applications

  34. PET • Any PET detector can be simulated with simple text format • Utility to create siple geometries from a few parameters (number of crystals per block, number of block per ring, radius, ...) • Several sensitive detectors types selectable by user commands • User can create it own one and make it a plug-in • Automatic creation of hits with detailed information /gamos/assocSD2LogVol GmSDSimple SD_TYPE VOLUME_NAME • Writing hits into text or binary file • Retrieving them in next job (for doing parametric studies) • Format compatible with STIR software • Digitizer and reconstructed hits framework and examples • Detector effects • Energy resolution • Time resolution • Dead time (paralyzable / non-paralyzable) • Measuring time • PET coincidence time LSO LaBr3

  35. PET • Table of PET classification • True / scattered / random coincidences / scattered&random • PET line far or close to vertex • Optionally merge hits if there is more than one because of Compton interactions • Histograms of hits or reconstructed hits with a user command • Histograms of positron history • Histograms of PET information • Several detectors simulated with GAMOS: • CTI ECAT Exact (922) • GE Discovery ST (PET/CT) • ClearPET • BrainPET (optical photons) • Pixel-PET prototype • Results agree with data

  36. Radiotherapy: accelerator • Any accelerator (with any kind of MLCs) can be simulated with simple text format • Building complicated parts (MLCs/jaws/applicators) with a few parameters under progress • Write phase space files in IAEA format • Several Z planes in the same job • Stop after last Z plane or not • Save header after N events (not to lose everything if job is aborted) • Save extra info: • Regions particle traversed • Regions particle created • Regions particle interacted • Particle origin Z • More can be easily added (they are plug-in’s) • Kill particles at big XY at different Z’s • Automatic or user-defined limits • Command for replication of particles at a given Z (no need to write phase space) • Command for optional histograms by particle type at each Z plane

  37. Radiotherapy: read PS files • Reading IAEA phase space files • Displace or rotate phase space particles • Reuse phase space particles • Optional automatic calculation of reuse number • Optional mirroring in X, Y or XY • Recycle phase space files • Command for skipping of first N events • Command for optional histograms of particles read • Filter particles by extra info • Also read EGSnrc phase space format

  38. Use DICOM files Read GEANT4 format (example advanced/medical/DICOM: DICOM  ASCII) Read EGS format Split one material in several if voxel densities are different User defines an interval width and a new material is created for the densities at each interval Displace or rotate read-in phantom geometry PTV/CTV/GTV management Simple phantoms can be created with a few commands Define voxel limits Define number of voxels Define material for each Z plane Geant4 allows to build parallel worlds But only geometry is seen, not materials (=no interactions) We have developed a tool that allows to insert objects in phantom geometries and produce the interactions in them Realistic simulation of brachytherapy sources or ionisation chambers! Radiotherapy: phantom geometry

  39. Radiotherapy: dose in phantom • Fast navigation (4-5 times faster than any other G4 algorithm) • Released in official Geant4 release • Different printing formats in each run • Text in standard output • Dose histograms (X, Y, Z, XY, XZ, YZ, dose, dose-volume) • User can define several XY, XZ, YZ planes (= simple dose visualisation) • File with dose and error at each voxel • File with dose and dose2 at each voxel (to properly take into account correlations) • Dose in total or by event • Proper management of original number of events when reading phase space files

  40. Radiotherapy gMocren visualisation of DICOM geometry and tracks gMocren view of GEANT4 geometry and tracks transported with the new algorithm gMocren view of GEANT4 geometry and tracks transported with the new algorithm gMocren view of GEANT4 geometry and tracks transported with the new algorithm gMocren view of GEANT4 geometry and tracks transported with the new algorithm gMocren view of GEANT4 geometry and tracks transported with the new algorithm

  41. Radiotherapy IMRT dose visualisation with CIEMAT’s tool (MIRAS) gMocren view of GEANT4 geometry and tracks transported with the new algorithm gMocren view of GEANT4 geometry and tracks transported with the new algorithm gMocren view of GEANT4 geometry and tracks transported with the new algorithm gMocren view of GEANT4 geometry and tracks transported with the new algorithm gMocren view of GEANT4 geometry and tracks transported with the new algorithm

  42. Radiotherapy: analysis Datos exper. Datos exper. - GAMOS - GAMOS Dose (normalized) A set of easy-to-use executables and ROOT scripts Phase space files • Sum phase space files • Analyse phase space files • Statistics • Histograms by particle type at each Z plane (= histograms when writing PS) • Compare two phase space files Dose files • Sum dose files • Analyse dose files • Statistics • Dose histograms (X, Y, Z, XY, XZ, YZ, dose, dose-volume) (= histos when writing dose) • Compare two dose files • GUI under development (MIRAS project) Position (mm) Dose (normalized) Position (mm)

  43. Radiotherapy: optimisation • GEANT4 electromagnetic parameters are not optimised for radiotherapy • They cover a wide range of energy and applications  they have to be conservative • We have started to optimise GEANT4 electromagnetic parameters for radiotherapy: http://kds.kek.jp/contributionDisplay.py?contribId=50&sessionId=2&confId=2027 VARIAN 2100 gamma accelerator: 106 events on Pentium Dual-Core 3 GHz * Same parameters as for 6MeV Dose in 104 5x5x3 mm water phantom: 106 events on Pentium Dual-Core 3 GHz Dose in 4.5 106 patient, 23 materials: 106 events on Pentium Dual-Core 3 GHz

  44. Radiotherapy: variance reduction • Three bremsstrahlung splitting techniques are available through user commands • Uniform bremsstrahlung splitting • Z-plane direction bremsstrahlung splitting • Particle splitting • Split particles at each interaction to get equal weights at phantom • Inspired on EGSnrc DBS • Preliminary efficiency gain of a factor 45 (EGSnrc DBS a factor 80 in same accelerator) • Other techniques are under study

  45. Documentation Installation Usage

  46. Documentation • User’s Guide: • Installation • All available functionality • How to provide new functionality by creating a plug-in • Examples: • A simple one and a few more complicated ones • /gamos/setParam GmGeometryFromText:FileName mygeom.txt • /gamos/geometry GmGeometryFromText • /gamos/physics GmEMPhysics • /gamos/generator GmGenerator • /run/initialize • /gamos/generator/addIsotopeSource myF18 F18 1.E6*becquerel • /run/beamOn 10

  47. Documentation • Tutorials: • Three tutorials • PET tutorial • Radiotherapy tutorial • plug-in tutorial • Propose about 15 exercises each • Explained in detail • Increasing in difficulty • Reference output provided • Solutions provided • 4 GAMOS tutorial courses have been given • About 70 attendees

  48. Installation • GAMOS is freely available from CIEMAT web • User registers and downloads installation scripts • We provide a no-choice but very easy way: one-line installation • source installGamos.csh/sh $HOME/gamos • Installs and compiles SEAL, CLHEP, Geant4 and (optionally) ROOT in one directory • GAMOS compiles = Geant4 • Optionally an expert user can make several choices • Current installation tested in Scientific Linux 4, Fedora Core 6,7,8 and Ubuntu 8.04 • But installing a software on linux is never easy… • We have paid an expert to work for three months on GAMOS installation (autoconfiguration tools) • Starting end of May • And also on the Web and automatic testing

  49. Release and user support • One release every three months • Minor releases in between • Major releases are checked in two different platforms • 50 tests are run • An automatic comparison tool is under progress • Two mailing lists for support: • For users: gamos_users@ciemat.es • For developers: gamos_developers@ciemat.es

  50. Usage • Several groups are using GAMOS in Spain: • CIEMAT (Medical Physics Applications): PET • CIEMAT (Dosimetry): microdosimetry • CSIC: microdosimetry • Univ. Sevilla: gamma radiotherapy • Univ. Navarra: brachytherapy • Hosp. General Albacete: gamma radiotherapy • CIEMAT-Hosp. Puerta de Hierro, Madrid: gamma radiotherapy, tomotherapy • CNM Barcelona: effects in detector electronics And abroad: • CEADEN (Cuba): PET • Univ. UPCH (Perou): PET • Univ. UNSAAC (Perou): astroparticle physics • Univ. Autónoma Chiapas (Mexico): gamma radiotherapy • Vrije Univ. Brussel (Belgium): PET • INFN Torino: PET And some groups (including Geant4 developers) have shown interest in helping in GAMOS development: • Hosp. Santa e Croce (Torino): radiotherapy • A group in the USA: use GAMOS as base for a hadrontherapy application

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