GAMOS tutorial PET Exercises Anaphe -- OO Data Analysis using C++ and Python 15 June 2018 GAMOS tutorial PET Exercises Pedro Arce Dubois CIEMAT http://fismed.ciemat.es/GAMOS Pedro Arce Introducción a GEANT4 Andreas Pfeiffer, CERN/IT-API, andreas.pfeiffer@cern.ch

PET simulation Exercises Anaphe -- OO Data Analysis using C++ and Python 15 June 2018 PET simulation Exercises Ex. 0: Installation Ex. 1: Basic example Ex. 2: Define PET geometry Obtain information about what is happening in a PET Ex. 3: Detector effects Ex. 4: Store results in file The exercises are sequential Use the commands of the previous exercise (only change what indicated Pedro Arce Introducción a GEANT4 Andreas Pfeiffer, CERN/IT-API, andreas.pfeiffer@cern.ch

Exercise 0: installation Anaphe -- OO Data Analysis using C++ and Python Exercise 0: installation 15 June 2018 Download installation scripts from http://wwwae.ciemat.es/~arce/GAMOS/download/GAMO S.1.9.0/scripts.tgz Uncompress it tar xvzf scripts.tgz Install it (under csh) cd scripts csh source installGamos.csh $HOME/gamos Pedro Arce Introducción a GEANT4 Andreas Pfeiffer, CERN/IT-API, andreas.pfeiffer@cern.ch

Exercise 1: simple geometry Anaphe -- OO Data Analysis using C++ and Python 15 June 2018 Exercise 1: simple geometry Geometry: Tube radius 100cm length 200cm of Water, axis along X inside Box 30cm X 30cm X 40cm of Aluminun Standard electromagnetic physics Primary particle: gamma 10 MeV at (0,0,0) in random direction Pedro Arce Introducción a GEANT4 Andreas Pfeiffer, CERN/IT-API, andreas.pfeiffer@cern.ch

Exercise 1b: visualisation Anaphe -- OO Data Analysis using C++ and Python 15 June 2018 Exercise 1b: visualisation Visualize geometry and tracks Use OGLIX Use VRML2FILE Pedro Arce Introducción a GEANT4 Andreas Pfeiffer, CERN/IT-API, andreas.pfeiffer@cern.ch

Exercise 1c: use different e.m. physics Anaphe -- OO Data Analysis using C++ and Python 15 June 2018 Exercise 1c: use different e.m. physics Use low energy electromagnetic Use Penelope (Make statistics on processes/particles) Pedro Arce Introducción a GEANT4 Andreas Pfeiffer, CERN/IT-API, andreas.pfeiffer@cern.ch

PET Exercise 2a: PET geometry Anaphe -- OO Data Analysis using C++ and Python 15 June 2018 PET Exercise 2a: PET geometry 2 cm X 2 cm X 10 cm LSO crystals LSO: Lu 76.4016%, Si 6.1328%, O 17.4656% Block of 8X8 crystals 20 blocks in a ring of radius 60 cm Pace 5 rings blocks along Z separated 10 cm Water sphere of radius 2 cm at the centre of the rings Source of 511 keV photons at (0,0,0) towards the X axis Pedro Arce Introducción a GEANT4 Andreas Pfeiffer, CERN/IT-API, andreas.pfeiffer@cern.ch

PET Exercise 2b: use F18 as source Anaphe -- OO Data Analysis using C++ and Python 15 June 2018 PET Exercise 2b: use F18 as source Place F18 homogeneously distributed in the water sphere Activity: 1 milliCurie Pedro Arce Introducción a GEANT4 Andreas Pfeiffer, CERN/IT-API, andreas.pfeiffer@cern.ch

PET Exercise 2c: obtain information Anaphe -- OO Data Analysis using C++ and Python 15 June 2018 PET Exercise 2c: obtain information Make info about the phsycis processes that occur Make the crystal sensitive detector and produce signals (hits) Obtain histograms about hits quantities (energy, position, …) Get detailed info about Compton and Photoelectric effect in crystals Pedro Arce Introducción a GEANT4 Andreas Pfeiffer, CERN/IT-API, andreas.pfeiffer@cern.ch

PET Exercise 2c: low energy physics Anaphe -- OO Data Analysis using C++ and Python 15 June 2018 PET Exercise 2c: low energy physics Use GEANT4 low energy electromagnetic package, instead of standard electromagnetic package Observe differences in energy distribution Observe differences in processes occurring Observe differences in CPU time Pedro Arce Introducción a GEANT4 Andreas Pfeiffer, CERN/IT-API, andreas.pfeiffer@cern.ch

PET Exercise 2d: Classify events as PET events Anaphe -- OO Data Analysis using C++ and Python 15 June 2018 PET Exercise 2d: Classify events as PET events A PET event is the one that has two signals of energy about 511 keV in the crystals Classification is done looking at the reconstructed hits Define a RecHitBuilder that sums all the energy of the crystals in a block of 8X8, and assign the position as the centre of the crystal with biggest energy Count % of PET events How many are false coincidences In how many the line joining the two crystals passes too far from the F18 positron Pedro Arce Introducción a GEANT4 Andreas Pfeiffer, CERN/IT-API, andreas.pfeiffer@cern.ch

PET Exercise 3a: Energy resolution Anaphe -- OO Data Analysis using C++ and Python 15 June 2018 PET Exercise 3a: Energy resolution Set crystal energy resolution as 20% Observe differences in hits energy Observe differences in number of PET events Pedro Arce Introducción a GEANT4 Andreas Pfeiffer, CERN/IT-API, andreas.pfeiffer@cern.ch

PET Exercise 3b: Dead time Anaphe -- OO Data Analysis using C++ and Python 15 June 2018 PET Exercise 3b: Dead time Set the dead time of crystals as 1 microseconds When a crystal takes signal, full block of 8X8 crystal becomes dead for a time Observe differences in number of PET events Pedro Arce Introducción a GEANT4 Andreas Pfeiffer, CERN/IT-API, andreas.pfeiffer@cern.ch

PET Exercise 3b: Measuring time Anaphe -- OO Data Analysis using C++ and Python 15 June 2018 PET Exercise 3b: Measuring time Set the measuring time of crystals as 1 microseconds Two signals in a crystal cannot be distinguised if they differe less than a given amount Observe differences in number of PET events Observe differences in recontructed hits Pedro Arce Introducción a GEANT4 Andreas Pfeiffer, CERN/IT-API, andreas.pfeiffer@cern.ch