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Geant4 - an Object-Oriented Toolkit for Simulation in HEP
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HADR02
Example and DMJET: V.Ivanchenko, A.Ivanchenko,
UrQMD: Kh Abdel-Waged et al, A. Dotti
CRMC: A. Ribon (with contributions by T. Pierog and A. Tykhonov)
CERN, Geneva, Switzerland
Geant4 Associate International
University of Bordeaux, CENBG/IN2P3/CNRS
(ESA contract 22712/09/NL/AT)
This example application is providing simulation of ion beam interaction with different
targets. Hadronic aspects of beam target interaction are demonstrated in the example
including longitudinal profile of energy deposition, spectra of secondary particles,
isotope production spectra. The results are presenting in a form of average numbers
and histograms. All ion/ion models of Geant4 are available.
In addition an interface to the FORTRAN code UrQMD-1.3rc developed by Kh, Abdel-Waged et al
for the KACST/NCMP. UrQMD model by S.A.Bass et al. Prog.Part.Nucl.Phys. 41 (1998) 225
and M.Bleicher et al. J.Phys. G25 (1999) 1859.
UrQMD can be used only for ion-ion physics or for all hadronic inelastic interactions.
The interface to the Cosmic Ray Monte Carlo (CRMC) allows to use generators -
such as EPOS, DPMJET, SIBYLL etc. - for hadron-nucleus and nucleus-nucleus collisions
at very high energies.
INSTALLATION
For simulation with Geant4 native models installation procedure is the same as for
other examples.
HOW TO RUN
To run the example:
Hadr02 <yourmacro> QGSP_BIC
The last parameter is optional. It is the name of Geant4 reference Physics List,
alternatively Physics List can be defined via environment variable
setenv PHYSLIST QGSP_BIC
ACTIVATION OF URQMD INTERFACE
UrQMD 1.3 FORTRAN code is NOT provided with Geant4 code-base.
You can get UrQMD code from UrQMD code website: http://urqmd.org
The Geant4 interface has been developed and tested against urqmd-1.3cr
Once the tarball urqmd-1.3cr.tar.gz has been downloaded copy it in the
urqmd1_3 directory of this example.
To compile support for UrQMD interface in the example define the environment
variable G4_USE_URQMD. i.e. by typing:
setenv G4_USE_URQMD 1
Two possible uses of UrQMD interface are possible: use UrQMD code only for
ion-ion interactions or use the provided UrQMD physics list (all hadron inelastic interactions
use UrQMD).
To run the example with UrQMD only for ion-ion physics:
Hadr02 urqmd.in QGSP_BIC
The last parameter is optional. It is the name of Geant4 reference Physics List on
top of which a new ion physics is added. Alternatively Physics List can be defined via
environment variable
setenv PHYSLIST QGSP_BIC
To run the example with the full UrQMD physics:
Hadr02 default.in UrQMD
or:
setenv PHYSLIST UrQMD
Hadr02 default.in
UrQMD physics list can be used in any application, releavant headers and source files (*UrQDM*)
should be copied in your application source tree, together with the urqmd1_3 sub-directory.
Your application makefile should also be modified following the example of the makefile for this
example.
ACTIVATION OF CRMC INTERFACE
The CRMC (Cosmic Ray Monte Carlo) interface is NOT provided with Geant4 code-base.
Moreover, the CRMC code that is publicly available in: https://github.com/alisw/crmc
is not appropriate for Geant4 (because CRMC assumes that a large number of
interactions of the same type - i.e. hadron projectile type, projectile energy,
and target nucleus - should be simulated, whereas for Geant4 we need from CRMC
the simulation of one, single hadron-nucleus interaction, for different types of
interaction at each call).
A modified version of the CRMC interface for Geant4 applications has been kindly
prepared by Tanguy Pierog (IKP), and can be obtained via the following command:
svn co https://devel-ik.fzk.de/svn/mc/crmc/branches/geant4
but you need to contact him (email: Tanguy.Pierog@kit.edu ) to get the access
permission (i.e. a username and password to access this repository).
We are pleased to acknowledge here also the contribution of Andrii Tykhonov
(Universite' de Geneve, and member of the DAMPE Collaboration) who made the
first prototype interface between Geant4 and CRMC, and shared his expertise
and implementation with us.
Assuming that this special version of CRMC is installed in the subdirectory
crmc_interface/ , you need first to build it : please look at the README file,
crmc_interface/README for detailed instructions on how to build it. In short:
1. Install ROOT
2. Install HepMC (and define the corresponding environmental variable HEPMC_PREFIX)
3. Define the following environmental variables:
export HEP_ROOT=${HEPMC_PREFIX}
export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:${HEP_ROOT}/lib
export CPATH=${CPATH}:${PWD}/Build/src
export CPATH=${CPATH}:${PWD}/src
export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:${PWD}/crmc_interface/Build/lib
4. cd crmc_interface/
5. mkdir Build/ ; cd Build/ # Subdirectory where to build and install CRMC
6. cmake ../
7. make
8. make install # Yes, you need also to install it (in the same directory)!
After you have built CRMC you can build the Hadr02 application that uses it as follows:
1. Define the following environmental variable (in addition to the environmental
variables defined above, needed to build CRMC):
export G4_USE_CRMC=1
2. cd /your-geant4/examples/extended/hadronic/Hadr02
2. mkdir Build/ ; cd Build/ # Subdirectory where to build Hadr02
3. cmake -DG4_USE_CRMC=ON -DCRMCROOT=${PWD}/crmc_interface/ \
-DCMAKE_PREFIX_PATH=/your/geant4/installation ../
4. make
To run the application:
1. Define the following environmental variable (besides the previous ones):
export PHYSLIST=CRMC_FTFP_BERT
2. cd /your-geant4/examples/extended/hadronic/Hadr02/Build
3. ./Hadr02 crmc.in
which runs the special "CRMC_FTFP_BERT" physics list, defined in this example,
which consists of using the standard FTFP_BERT physics list for hadrons of
kinetic energies below 100 GeV, while using CRMC above 110 GeV : in the interval
between 100 and 110 GeV, there is the transition between FTFP and CRMC (which
means that one of these two models is randomly chosen for each interaction,
with a probability which is 100% (0%) for FTFP (CRMC) at 100 GeV, and
decreases (grows) linearly to 0% (100%) for FTFP (CRMC) at 110 GeV.
Which of the MC generators of CRMC is actually used is specified in the file:
include/G4CRMCModel.hh
(search for string "***LOOKHERE***" : these are the available choices:
EPOS LHC (0) - the default - , EPOS 1.99 (1), SIBYLL 2.3c (6), and
DPMJET 3 (12) ).
Notice that we use CRMC only for inelastic final-state of pion- , kaon- ,
proton- , neutron- and ion-nuclear interactions, whereas for the rest
(i.e. elastic and inelastic cross sections, elastic final-state interactions,
hyperon- , antihyperon- , antinucleon- and light anti-ion nuclear interactions)
we use Geant4 FTFP_BERT.
GEOMETRY
The Target volume is a cylinder placed inside Check cylindrical volume. The
Check volume is placed inside the World volume. The radius and the length of
the Check volume are 1 mm larger than the radius and the length of the Target.
The material of the Check volume is the same as the World material. The World
volume has the sizes 10 mm larger than that of the Target volume. Any material
from the Geant4 database can be defined. The default World material is
G4Galactic and the default Target material is aluminum. The Target is
subdivided on number of equal slices. Following UI commands are available to
modify the geometry:
/testhadr/TargetMat G4_Pb
/testhadr/WorldMat G4_AIR
/testhadr/TargetRadius 10 mm
/testhadr/TargetLength 20 cm
/testhadr/NumberDivZ 200
Beam direction coincides with the target axis and is Z axis in the global
coordinate system. G4ParticleGun is used as a primary generator. The energy
and the type of the beam can be defined via standard UI commands
/gun/energy 150 GeV
/gun/particle ion
/gun/ion 6 12
Default beam position is -(targetHalfLength + 5*mm) and direction along Z axis.
Beam position and direction can be changed by gun UI commands:
/gun/position 1 10 3 mm
/gun/direction 1 0 0
however, position command is active only if before it the flag is set
/testhadr/DefaultBeamPosition false
SCORING
The scoring is performed with the help of UserStackingAction class and a
sensitive detector class associated with a target slice.
Each secondary particle is scored by the StackingAction. In
the StackingAction it is also possible to kill all or only EM (e+, e-, gamma)
secondary particles
/testhadr/killAll
/testhadr/KillEM
To control running the following options are available:
/run/printProgress 10
PHYSICS
PhysicsList of the application uses components, which are distributed with
Geant4 in /geant4/physics_lists subdirectory.
Reference Physics Lists are used and the environment variable PHYSLIST should
be defined.
Additionally it is possible to add ion-ion interactions using UI command
/testhadr/ionPhysics HIJING
/testhadr/ionPhysics QrQMD
VISUALIZATION
For interactive mode G4 visualization options and variables should be
defined, then the example should be recompiled:
gmake visclean
gmake
The vis.mac file can be used an example of visualization. The following command can
be used:
/testhadr/DrawTracks charged
/testhadr/DrawTracks charged+n
/testhadr/DrawTracks neutral
/testhadr/DrawTracks all
HISTOGRAMS
All histograms are normalized to the number of events.
Gabriele Cosmo