------------------------------------------------------------------- $Id: README 73136 2013-08-19 14:28:09Z sincerti $ ------------------------------------------------------------------- ========================================================= Geant4 - Microdosimetry example ========================================================= README file ---------------------- CORRESPONDING AUTHOR S. Incerti (a, *), V. Ivanchenko (b), M. Karamitros (a) a. Centre d'Etudes Nucleaires de Bordeaux-Gradignan (CENBG), IN2P3 / CNRS / Bordeaux 1 University, 33175 Gradignan, France b. G4AI Ltd, UK * e-mail:incerti@cenbg.in2p3.fr ---->0. INTRODUCTION. The microdosimetry example simulates the track of a 5 MeV proton in liquid water. Geant4 standard EM models are used in the World volume while Geant4-DNA models are used in a Target volume, declared as a Region. This example is provided by the Geant4-DNA collaboration. These processes and models are further described at: http://geant4-dna.org Any report or published results obtained using the Geant4-DNA software shall cite the following Geant4-DNA collaboration publication: Med. Phys. 37 (2010) 4692-4708 We also suggest these other references related to this example: Nucl. Instrum. and Meth. B 273 (2012) 95-97 Prog. Nucl. Sci. Tec. 2 (2011) 898-903 ---->1. GEOMETRY SET-UP. The geometry is a 1 mm side cube (World) made of liquid water containing a smaller cubic Target volume of liquid water, which dimensions are twenty times smaller than the dimensions of the World volume. ---->2. SET-UP Make sure G4LEDATA points to the low energy electromagnetic libraries. The variable G4ANALYSIS_USE must be set to 1. The code can be compiled with cmake. It works in MT mode. ---->3. HOW TO RUN THE EXAMPLE In interactive mode, run: ./microdosimetry The macro microdosimetry.mac is executed by default. To get visualization, make sure to uncomment the #/control/execute vis.mac line in the macro (not recommended). ---->4. PHYSICS This example shows: - how to use the Geant4-DNA processes, - how to affect them a number - how to combine them with Standard EM Physics. A simple electron capture process is also provided in order to kill electrons below a chosen energy threshold, set in the Physics list. Look at the PhyscisList.cc file. ---->5. SIMULATION OUTPUT AND RESULT ANALYZIS The output results consists in a microdosimetry.root file, containing for each simulation step: - the type of particle for the current step - the type of process for the current step - the track position of the current step (in nanometers) - the energy deposit along the current step (in eV) - the step length (in nm) - the total enery loss along the current step (in eV) This file can be easily analyzed using for example the provided ROOT macro file plot.C; to do so : * be sure to have ROOT installed on your machine * be sure to be in the microdosimetry directory * launch ROOT by typing root * under your ROOT session, type in : .X plot.C to execute the macro file * alternatively you can type directly under your session : root plot.C The naming scheme on the displayed ROOT plots is as follows (see SteppingAction.cc): -particles: e- : 1 proton : 2 hydrogen : 3 alpha : 4 alpha+ : 5 helium : 6 -processes: e-_G4DNAElastic 11 e-_G4DNAExcitation 12 e-_G4DNAIonisation 13 e-_G4DNAAttachment 14 e-_G4DNAVibExcitation 15 eCapture 16 proton_G4DNAExcitation 17 proton_G4DNAIonisation 18 proton_G4DNAChargeDecrease 19 hydrogen_G4DNAExcitation 20 hydrogen_G4DNAIonisation 21 hydrogen_G4DNAChargeIncrease 22 alpha_G4DNAExcitation 23 alpha_G4DNAIonisation 24 alpha_G4DNAChargeDecrease 25 alpha+_G4DNAExcitation 26 alpha+_G4DNAIonisation 27 alpha+_G4DNAChargeDecrease 28 alpha+_G4DNAChargeIncrease 29 helium_G4DNAExcitation 30 helium_G4DNAIonisation 31 helium_G4DNAChargeIncrease 32 hIoni 33 eIoni 34 --------------------------------------------------------------------------- Should you have any enquiry, please do not hesitate to contact: incerti@cenbg.in2p3.fr