Warning, /geant4/examples/extended/medical/dna/splitting/README is written in an unsupported language. File is not indexed.
0001 =================================================================
0002 Geant4 - splitting
0003 =================================================================
0004
0005
0006 Authors: J. A. Ramos-Mendez*, B. A. Faddegon
0007
0008 Department of Radiation Oncology, University of California San Francisco
0009 * Corresponding author, email to joserm84@gmail.com
0010
0011 This example is provided by the Geant4-DNA collaboration.
0012
0013 These processes and models are further described at:
0014 http://geant4-dna.org
0015
0016 Any report or published results obtained using the Geant4-DNA software shall
0017 cite the following Geant4-DNA collaboration publications:
0018 Phys. Med. 31 (2015) 861-874
0019 Med. Phys. 37 (2010) 4692-4708
0020
0021 If use this example, please cite
0022 J Ramos-Mendez, et. Al. Phys. Med. Biol. 62(15), 5908-5925, (2017) DOI: 10.1088/1361-6560/aa7831
0023
0024 ---> 1. A brief description
0025
0026 The splitting example uses variance reduction to improve the computational
0027 efficiency of calculations of ionization cluster size distributions. Ionization
0028 events are scored in a nanoscaled cylinder. Ionized electrons generated by
0029 the first generation of secondary electrons are split, i.e. new clone electrons
0030 are generated, labeled and propagated. The label is used to classify those
0031 new particles as if they were produced by independent histories to avoid
0032 overlapping of tracks at final analysis. The splitting is performed only
0033 if the ionization event occurred in the cylinder.
0034
0035 Geant4-DNA processes are used.
0036
0037 The example package contains:
0038 - source files (src, include)
0039 - README
0040 - .in, plot.C and visualization macro files
0041
0042 **** 2. Set-up.
0043
0044 The geometry is a nanoscaled cylinder centered in the world. The medium is
0045 water everywhere. The dimensions can be defined with
0046 /detector/diameter 6 nm
0047 /detector/length 10 nm
0048
0049 User can define the split number (default is 1, i.e. no split)
0050 with:
0051
0052 /vrt/numberOfSplit 10
0053
0054 **** 3. How to run the example.
0055 In interactive mode, run:
0056 ./splitting
0057 Idle> /control/execute vis.mac
0058
0059 In batch mode , run:
0060
0061 ./splitting run.mac
0062
0063 To get visualization, make sure to uncomment the #/control/execute vis.mac line in the macro.
0064
0065 **** 4. The physics
0066
0067 This example shows:
0068 - how to use the Geant4-DNA processes,
0069 - how to implement the splitting via G4WrappedProcess
0070 - how to set the splitting in specific region
0071 - how to propagate new track information to secondary particles
0072
0073 A simple electron capture process is also provided in order to kill electrons
0074 below a chosen energy threshold, set in the Physics list.
0075
0076 Look at the PhyscisList.cc file.
0077
0078 **** 5. Simulation output
0079
0080 The output results consists in two histograms in root format
0081
0082 - the energy deposit in the cylindrical target
0083 - the frequency distribution of ionization cluster size
0084
0085 NOTE: Every time a value is added to a ROOT histogram, it contributes to the statistics.
0086 For this example, to correct estimate the uncertainties is recommended to split the simulation into
0087 several jobs and to calculate the statistics from them: batch mode. Otherwise, the statistical
0088 uncertainty may be underestimated.
0089
0090 **** 6. Contacts
0091
0092 If you have any questions or wish to notify of updates and/or modification please contact:
0093
0094 J. Ramos-Mendez at joserm84@gmail.com
0095
0096 **** Acknowledgments :
0097
0098 Sebastien Incerti (CNRS) for its guidance
0099
0100
