Import Geant4 6.2.0 source tree
This commit is contained in:
Gabriele Cosmo
@@ -0,0 +1,553 @@
|
||||
|
||||
LXe Example
|
||||
-----------
|
||||
|
||||
**************
|
||||
*Classes Used*
|
||||
**************
|
||||
|
||||
main()
|
||||
------
|
||||
|
||||
==> Use G4UItcsh if available
|
||||
|
||||
==> Provide interactive and macro mode
|
||||
|
||||
G4VModularPhysicsList
|
||||
------------------
|
||||
(class: LXePhysicsList)
|
||||
|
||||
==> Registers General, EM, Muon, and Optical physics lists
|
||||
|
||||
==> define particles; including *** G4OpticalPhoton ***
|
||||
define processes; including *** G4Cerenkov ***
|
||||
*** G4Scintillation ***
|
||||
*** G4OpAbsorption ***
|
||||
*** G4OpRayleigh ***
|
||||
*** G4OpBoundaryProcess ***
|
||||
*** G4OpWLS ***
|
||||
|
||||
G4VUserDetectorConstruction
|
||||
---------------------------
|
||||
(class: LXeDetectorConstruction)
|
||||
|
||||
==> define material: LXe (liquid xenon), Aluminum, Air, Vacuum, Glass,...
|
||||
define G4Box geometry with aluminum housing and LXe volume inside
|
||||
define G4Tubs placed around the housing walls
|
||||
define G4Sphere to demonstrate skin surfaces inside volumes
|
||||
*** add G4MaterialPropertiesTable to G4Material ***
|
||||
*** define G4OpticalSurface(s) ***
|
||||
*** define G4LogicalBorderSurface(s) ***
|
||||
*** define G4LogicalSkinSurface(s) ***
|
||||
*** add G4MaterialPropertiesTable to G4OpticalSurface(s)***
|
||||
|
||||
==> Mesenger to change many of the dectector geometry properties
|
||||
|
||||
==> Uses a alternative style of geometry definition. See "Geometry" section.
|
||||
|
||||
G4VUserPrimaryGeneratorAction
|
||||
-----------------------------
|
||||
(class: LXePrimaryGeneratorAction)
|
||||
|
||||
==> Use G4ParticleGun to shoot a 511 keV gamma through the housing into
|
||||
liquid xenon scintillator
|
||||
|
||||
G4UserStackingAction
|
||||
--------------------
|
||||
(class: LXeStackingAction)
|
||||
|
||||
==> show how to count the number of secondary particles in an event
|
||||
differentiates between different creator processes
|
||||
|
||||
G4UserRunAction
|
||||
---------------
|
||||
(class: LXeRunAction)
|
||||
|
||||
==> Call recorder class for begin and end of run
|
||||
|
||||
G4UserSteppingAction
|
||||
--------------------
|
||||
(class: LXeSteppingAction)
|
||||
|
||||
==> Identify which secondaries were generated during a particular step
|
||||
|
||||
==> ***Count reflections/absorptions/detections due to G4OpBoundaryProcess***
|
||||
***Count absorptions due to G4OpAbsorption ***
|
||||
Manually trigger a sensitive detector when a boundary process detects
|
||||
|
||||
==> Call recorder class at end of step
|
||||
|
||||
G4UserTrackingAction
|
||||
____________________
|
||||
(class: LXeTrackingAction)
|
||||
|
||||
==> Determine if the trajectory should be drawn by checking if it hit the
|
||||
sphere(if enabled) and a pmt.
|
||||
|
||||
==> Call recorder class at end of track
|
||||
|
||||
G4UserEventAction
|
||||
-----------------
|
||||
(class: LXeEventAction)
|
||||
|
||||
==> Triggers drawing of trajectories
|
||||
|
||||
==> Calculates and stores data in a G4VUserEventInformation object
|
||||
|
||||
==> Outputs basic event data at end of event
|
||||
|
||||
==> Decides if the random seed should be saved for this event
|
||||
|
||||
==> Call recorder class at begin and end of event
|
||||
|
||||
G4VSensitiveDetector
|
||||
--------------------
|
||||
(classes: LXePMTSD, LXeScintSD)
|
||||
|
||||
==> Basic sensitive detectors keeping hit collections
|
||||
Keep one G4VHit object per hit
|
||||
or
|
||||
Keep one G4VHit object per volume containing hits
|
||||
|
||||
==> LXePMTSD decides if the hits it is creating should be redrawn
|
||||
|
||||
G4VHit
|
||||
------
|
||||
(classes: LXePMTHit, LXeScintHIT)
|
||||
|
||||
==> Store individual hit positions
|
||||
or
|
||||
Store a count of hits in a particular volume
|
||||
|
||||
==> Selectively redraw volumes containing hits at the end of event
|
||||
|
||||
G4VUserEventInformation & G4VUserTrackInformation
|
||||
-------------------------------------------------
|
||||
(classes: LXeUserEventInformation, LXeUserTrackInformation)
|
||||
|
||||
==> Store aditional information along with the G4Event/G4Track objects
|
||||
|
||||
G4VSteppingVerbose
|
||||
------------------
|
||||
(classes: LXeSteppingVerbose)
|
||||
|
||||
==> Custom verbose stepping output to use G4BestUnit and print current volume
|
||||
rather than next volume
|
||||
==> Same as ExN03SteppingVerbose but output reformated to fit nicer into
|
||||
tables.
|
||||
|
||||
G4UImessenger
|
||||
-------------
|
||||
(classes: LXeDetectorMessenger, LXeEventMessenger, LXeSteppingMessenger)
|
||||
|
||||
==> Create /LXe and /LXe/detector interactive command folders
|
||||
|
||||
==> Create new commands
|
||||
|
||||
==> See interactive help when running the example for descriptions of commands
|
||||
|
||||
G4Trajectory
|
||||
------------
|
||||
(class: LXeTrajectory)
|
||||
|
||||
==> Derived from G4Trajectory to use most of the basic trajectory functions
|
||||
already defined
|
||||
|
||||
==> Uses a coppied and modified version of DrawTrajectory from G4VTrajectory
|
||||
to enable/disable drawing of individual trajectories and to redefine
|
||||
the colours used
|
||||
|
||||
G4VisManager
|
||||
------------
|
||||
(class: LXeVisManager)
|
||||
|
||||
==> Initialize graphics systems geant4 is configured for
|
||||
|
||||
RecorderBase
|
||||
------------
|
||||
|
||||
==> Virtual class provided for recording of simulation data
|
||||
|
||||
==> Derive your own implementation from it and instantiate the recorder
|
||||
object in main()
|
||||
|
||||
==> For full description see RecorderBase.hh
|
||||
|
||||
**********
|
||||
*Geometry*
|
||||
**********
|
||||
The way the geometry is constructed is an experiment for a new, more object
|
||||
oriented, way to construct geometry. It seperates the concept of how a volume
|
||||
is built from where it is placed. Each major volume in the geometry is defined
|
||||
as a class derived from G4PVPlacement. In this example, just the main LXe
|
||||
volume, the WLS scintillator slab, and the WLS fibers were chosen. To place
|
||||
one of these volumes, simply create an instance of it with the appropriate
|
||||
rotation, translation, and mother volumes.
|
||||
|
||||
-------
|
||||
LXeMainVolume(G4RotationMatrix *pRot,
|
||||
const G4ThreeVector &tlate,
|
||||
G4LogicalVolume *pMotherLogical,
|
||||
G4bool pMany,
|
||||
G4int pCopyNo,
|
||||
LXeDetectorConstruction* c);
|
||||
-------
|
||||
|
||||
Also necessary are the pMany and pCopyNo variables with the same usage as in
|
||||
G4PVPlacement. Additionally, the detector construction must be passed to the
|
||||
main volume as a way to communicate the many parameters to the volume and its
|
||||
sub-volumes. The communication is done from the CopyValues() function which
|
||||
retrieves the information from the detector constructor.
|
||||
|
||||
Notably, the name and logical volume parameters are no longer part of the
|
||||
constructor. This is because they are both to be decided by the volume itself.
|
||||
The volume must specify its own name and a temporary logical volume. The
|
||||
constructor will then procede to define its logical volume in the normal way.
|
||||
Once complete, the logical volume can be assigned to the physical volume using
|
||||
the SetLogicalVolume() function.
|
||||
|
||||
To handle instances of the same type of volume, a new logical volume should not
|
||||
be defined for each one. Instead, the logical volume is kept as a static member
|
||||
and defined only once.
|
||||
|
||||
------
|
||||
if(!housing_log || updated){
|
||||
//...
|
||||
//Define logical volume
|
||||
//...
|
||||
}
|
||||
SetLogicalVolume(housing_log);
|
||||
------
|
||||
|
||||
The updated variable is to signal that the volume needs to be updated and a new
|
||||
logical volume made.
|
||||
|
||||
***********************************
|
||||
*Modifying the geometry at runtime*
|
||||
***********************************
|
||||
This example allows the user to modify the geometry definition at runtime. This
|
||||
is accomplished through LXeDetecotrMessenger, a derived class of G4UImessenger.
|
||||
The commands it adds change variables stored in LXeDetectorConstructor that
|
||||
are used when constructing the geometry. After changing these variables
|
||||
the /LXe/detector/update command must be issued to reconstruct the geometry
|
||||
with the new values.
|
||||
|
||||
------
|
||||
void LXeDetectorConstruction::UpdateGeometry(){
|
||||
// clean-up previous geometry
|
||||
G4SolidStore::GetInstance()->Clean();
|
||||
G4LogicalVolumeStore::GetInstance()->Clean();
|
||||
G4PhysicalVolumeStore::GetInstance()->Clean();
|
||||
|
||||
//define new one
|
||||
G4RunManager::GetRunManager()->DefineWorldVolume(ConstructDetector());
|
||||
G4RunManager::GetRunManager()->GeometryHasBeenModified();
|
||||
}
|
||||
|
||||
************************
|
||||
*PMT sensitive detector*
|
||||
************************
|
||||
The PMT sensitive detector cannot be triggered like a normal sensitive detector
|
||||
because the sensitive volume does not allow photons to pass through it. Rather,
|
||||
it detects them in the OpBoundary process based on an efficiency set on the
|
||||
skin of the volume.
|
||||
|
||||
------
|
||||
|
||||
G4OpticalSurface* photocath_opsurf=
|
||||
new G4OpticalSurface("photocath_opsurf",glisur,polished,
|
||||
dielectric_metal);
|
||||
G4double photocath_EFF[num]={1.,1.};
|
||||
G4double photocath_REFL[num]={0.,0.};
|
||||
G4MaterialPropertiesTable* photocath_mt = new G4MaterialPropertiesTable();
|
||||
photocath_mt->AddProperty("EFFICIENCY",Ephoton,photocath_EFF,num);
|
||||
photocath_mt->AddProperty("REFLECTIVITY",Ephoton,photocath_REFL,num);
|
||||
photocath_opsurf->SetMaterialPropertiesTable(photocath_mt);
|
||||
new G4LogicalSkinSurface("photocath_surf",photocath_log,photocath_opsurf);
|
||||
|
||||
------
|
||||
|
||||
A normal sensitive detector would have its ProcessHits
|
||||
function called for each step by a particle inside the volume. So, to record
|
||||
these hits with a sensitive detector we watched the status of the OpBoundary
|
||||
process from the stepping manager whenever a photon hit the sensitive volume
|
||||
of the pmt. If the status was 'Detection', we retrieve the sensitive detector
|
||||
from G4SDManager and call its ProcessHits function.
|
||||
|
||||
------
|
||||
|
||||
boundaryStatus=boundary->GetStatus();
|
||||
//Check to see if the particle was actually at a boundary
|
||||
//Otherwise the boundary status may not be valid
|
||||
//Prior to Geant4.6.0-p1 this would not have been enough to check
|
||||
if(thePostPoint->GetStepStatus()==fGeomBoundary){
|
||||
switch(boundaryStatus){
|
||||
//...
|
||||
case Detection: //Note, this assumes that the volume causing detection
|
||||
//is the photocathode because it is the only one with
|
||||
//non-zero efficiency
|
||||
{
|
||||
//Trigger sensitive detector manually since photon is
|
||||
//absorbed but status was Detection
|
||||
G4SDManager* SDman = G4SDManager::GetSDMpointer();
|
||||
G4String sdName="/LXeDet/pmtSD";
|
||||
LXePMTSD* pmtSD = (LXePMTSD*)SDman
|
||||
->FindSensitiveDetector(sdName);
|
||||
if(pmtSD)
|
||||
pmtSD->ProcessHits_constStep(theStep,NULL);
|
||||
break;
|
||||
}
|
||||
//...
|
||||
}
|
||||
|
||||
**********************
|
||||
*Modular Physics List*
|
||||
**********************
|
||||
Using a modular physics list is an easy way to organize the physics list into
|
||||
categories for easier maintenance. It can also assist with testing code
|
||||
by making it easy to disable an entire category of physics at once if
|
||||
necessary. The physics list instantiated in main() is a derived class of
|
||||
G4VModularPhysics list rather than the usual G4VUserPhysicsList. The only
|
||||
function aside from the constructor that is necessary in this class is
|
||||
SetCuts(). The constructor must register the other physics lists individually.
|
||||
|
||||
RegisterPhysics( new LXeGeneralPhysics("general") );
|
||||
|
||||
The other physics lists (the modules) are derived from G4VPhysicsConstructor
|
||||
and it is necessary to write the ConstructParticle() and ConstructProcess()
|
||||
functions for each list. They work in the same way as in G4VUserPhysicsList.
|
||||
|
||||
Do not create instances of the individual physics processes as members of the
|
||||
modules. Instead, use pointers to the processes and create the instances
|
||||
in the ConstructProcess() function. The reason for this is that the materials
|
||||
needed to build physics tables for the processes will not have been created
|
||||
at the time that the modules are created but will have been created before the
|
||||
ConstructProcess() function is called.
|
||||
|
||||
**********************************************************
|
||||
*Selectively drawing trajectories or highlighting volumes*
|
||||
**********************************************************
|
||||
In a simulation such as this one, where an average of 6000 trajectories are
|
||||
generated in a small space, there is little use in drawing all of them. There
|
||||
are two ways to select which ones to draw. The first of which is to decide
|
||||
while looping through the trajectory container which ones to draw and only call
|
||||
DrawTrajectory on the important ones. However, trajectories only contain a
|
||||
small portion of the information from the track it represents. This may not
|
||||
be enough to decide if a trajectory is worth drawing.
|
||||
|
||||
The alternative is to define your own trajectory class to store additional
|
||||
information to help decide if it should be drawn. To use your custom trajectory
|
||||
you must create it in the PreUserTrackingAction:
|
||||
|
||||
fpTrackingManager->SetTrajectory(new LXeTrajectory(aTrack));
|
||||
|
||||
Then at any point you can get access to the trajectory you can update the extra
|
||||
information within it. When it comes to drawing, you can then use this to
|
||||
decide if you want to call DrawTrajectory. Or you can call DrawTrajectory for
|
||||
all trajectories and have the logic decide how and if a trajectory should
|
||||
be drawn inside the DrawTrajectory function itself.
|
||||
|
||||
Selectively highlighting volumes is useful to show which volumes were hit. To
|
||||
do this, you simply need a pointer to the physical volume. With that, you can
|
||||
modify its vis attributes and instruct the vis manager to redraw the volume
|
||||
with the new vis attributes.
|
||||
|
||||
------
|
||||
G4VisAttributes attribs(G4Colour(1.,0.,0.));
|
||||
attribs.SetForceSolid(true);
|
||||
G4RotationMatrix rot;
|
||||
if(physVol->GetRotation())//If a rotation is defined use it
|
||||
rot=*(physVol->GetRotation());
|
||||
G4Transform3D trans(rot,physVol->GetTranslation());//Create transform
|
||||
pVVisManager->Draw(*physVol,attribs,trans);//Draw it
|
||||
------
|
||||
|
||||
In this case, it is done in Draw function of a PMT hit but it can be placed
|
||||
anywhere. The logic to decide if it should be drawn or not may be similar to
|
||||
the logic used in choosing which trajectories to draw.
|
||||
|
||||
See /LXe/detector/volumes/sphere in "UI commands" below for info on what
|
||||
trajectories are drawn in this simulation.
|
||||
|
||||
****************************
|
||||
*Saving random engine seeds*
|
||||
****************************
|
||||
At times it may be necessary to review a particular event of interest. To do
|
||||
this without redoing an entire run, which may take a long time, you must store
|
||||
the random engine seed from the beginning of the event. The run manager
|
||||
has some functions that help in this task.
|
||||
|
||||
G4RunManager::SetRandomNumberStore(G4bool)
|
||||
|
||||
When set to true, this causes the run manager to write the seed for the
|
||||
beginning of the current run to CurrentRun.rndm and the current event to
|
||||
CurrentEvent.rndm. However, at the beginning of each event this file will be
|
||||
overwritten with the new event. To keep a copy for a particular event there is
|
||||
a function to copy this file to run###evt###.rndm.
|
||||
|
||||
G4RunManager::rndmSaveThisEvent()
|
||||
|
||||
This can be done for every event so you can review any event you like but this
|
||||
may be awkward for runs with very large numbers of events. Instead, implement
|
||||
some form of logic in EndOfEventAction to decide if the event is worth saving.
|
||||
If it is, then call rndmSaveThisEvent(). By default, these files are stored in
|
||||
the current working directory. There is a function to change this as well.
|
||||
Typically you would call that at the same time SetRandomNumberStore. The
|
||||
directory to save in must exist first. GEANT4 will not create it for you.
|
||||
|
||||
G4RunManager::SetRandomNumberStoreDir(G4String)
|
||||
|
||||
**************
|
||||
*RecorderBase*
|
||||
**************
|
||||
RecorderBase is a virtual class to serve as a template for how to add
|
||||
histogram functionality to a GEANT4 application. To use it, derive a
|
||||
class from it and instantiate that in main(). Each of your user action classes
|
||||
to do any recording must have a pointer to this instance. Then at the end of
|
||||
the critical functions in each user action, call the appropriate recorder
|
||||
function. The recorder functions and the functions to call them from are listed
|
||||
here:
|
||||
|
||||
RecordBeginOfRun(const G4Run*)
|
||||
-Call from BeginOfRunAction()
|
||||
RecordEndOfRun(const G4Run*)
|
||||
-Call from EndOfRunAction()
|
||||
RecordBeginOfEvent(const G4Event*)
|
||||
-Call from BeginOfEventAction()
|
||||
RecordEndOfEvent(const G4Event*)
|
||||
-Call from EndOfEventAction()
|
||||
RecordTrack(const G4Track*)
|
||||
-Call from PostUserTrackingAction()
|
||||
RecordStep(const G4Step*)
|
||||
-Call from UserSteppingAction()
|
||||
|
||||
For the reasoning behind why it is done this way see RecorderBase.hh
|
||||
|
||||
*************
|
||||
*UI commands*
|
||||
*************
|
||||
The method to define UI commands is well documented in the GEANT4 documentation
|
||||
so will not be discussed here. This is a description of the commands added to
|
||||
this example.
|
||||
|
||||
Directories:
|
||||
/LXe/ - All custom commands belong below this directory
|
||||
/LXe/detector/ - Geometry related commands
|
||||
/LXe/detector/volumes/ - Commands to enable/disable volumes in the geometry
|
||||
|
||||
Commands:
|
||||
/LXe/saveThreshold <int, default = 4500>
|
||||
-Specifies a threshold for saving the random seed for an event. If the number
|
||||
of photons generated in an event is below this number then the random seed is
|
||||
saved to ./random/run###evt###.rndm. See "Saving random engine seeds".
|
||||
|
||||
/LXe/eventVerbose <int, default = 1>
|
||||
-Enables end of event verbose data to be printed. This includes information
|
||||
counted and calculated by the user action classes.
|
||||
|
||||
/LXe/pmtThreshold <int, default = 1>
|
||||
-Sets the PMT threshold in # of photons being detected by the PMT. PMTs below
|
||||
with fewer hits than the threshold will not count as being hit and will also
|
||||
not be highlighted at the end of the event.
|
||||
|
||||
/LXe/oneStepPrimaries <bool>
|
||||
-This causes primary particles to be killed after going only one step inside
|
||||
the scintillator volume. This is useful to view the photons generated during
|
||||
the initial conversion of the primary particle.
|
||||
|
||||
/LXe/forceDrawPhotons <bool>
|
||||
-Forces all optical photon trajectories to be drawn at the end of the event
|
||||
regardless of the scheme mentioned in /LXe/detector/volumes/sphere below.
|
||||
|
||||
/LXe/forceDrawNoPhotons <bool>
|
||||
-Forces all optical photon trajectories to NOT be drawn at the end of the
|
||||
event regardless of the scheme mentioned in /LXe/detector/volumes/sphere below.
|
||||
-If /LXe/forceDrawPhotons is set to true, this has no effect.
|
||||
|
||||
/LXe/detector/dimensions <double x y z> <unit, default = cm>
|
||||
-Sets the dimensions of the main scintillator volume.
|
||||
|
||||
/LXe/detector/housingThickness <double>
|
||||
-Sets the thickness of the housing surrounding the main detector volume.
|
||||
|
||||
/LXe/detector/pmtRadius <double> <unit, default = cm>
|
||||
-Sets the radius of the PMTs
|
||||
|
||||
/LXe/detector/nx
|
||||
/LXe/detector/ny
|
||||
/LXe/detector/nz
|
||||
-Sets the number of PMTs placed in a row along each axis.
|
||||
|
||||
/LXe/detector/reflectivity <double>
|
||||
-Sets the reflectivity of the inside of the aluminum housing. The geometry
|
||||
uses a default value of 1.00 for a fully reflective surface.
|
||||
|
||||
/LXe/detector/nfibers <int>
|
||||
-Sets the number of WLS fibers placed in the WLS scintillator slab. The
|
||||
geometry uses a default value of 15 fibers.
|
||||
|
||||
/LXe/detector/scintYieldFactor <double>
|
||||
-Sets the yield factor for the scintillation process. This is cumulative with
|
||||
the yield factor set on individual materials. Set to 0 to produce no
|
||||
scintillation photons.
|
||||
|
||||
/LXe/detector/update
|
||||
-Builds the new geometry based on any parameters that have been updated with
|
||||
the other UI commands. ***This must be called for the changes to take effect***
|
||||
|
||||
/LXe/detector/defaults
|
||||
-Resets all detector values customizable with commands above to their defaults.
|
||||
|
||||
/LXe/detector/volumes/sphere <bool>
|
||||
-Enables/disables the sphere placed inside the main scintillator volume. When
|
||||
the sphere is enabled, only photons that hit the sphere and hit a PMT are
|
||||
drawn. If it is disabled, then all photons that hit PMTs are drawn.
|
||||
|
||||
/LXe/detector/volumes/wls <bool>
|
||||
-Enables/disables the WLS scintillator slab containing WLS fibers. By default
|
||||
this is not part of the geometry. Enabling it will place it behind the LXe
|
||||
scintillator volume.
|
||||
|
||||
/LXe/detector/volumes/lxe <bool>
|
||||
-Enables/disables the main LXe scintillator volume. By default this is part of
|
||||
the geometry.
|
||||
|
||||
*************
|
||||
*Macro files*
|
||||
*************
|
||||
The following are the macro files included in this example and what they do.
|
||||
|
||||
LXe.in
|
||||
-This produces a standard event with a 511 keV gamma fired into the LXe volume.
|
||||
All values are left at their default states but verbose output has been
|
||||
enabled.
|
||||
|
||||
cerenkov.mac
|
||||
-This is to demonstrate the cerenkov process. It disables the scintillation
|
||||
process and uses a 200MeV mu+ to produce cerenkov photons. The volume has
|
||||
been resized and the number of pmts has been increased to more accurately
|
||||
show the cone. OneStepPrimaries has been enabled so that the cone does not fill
|
||||
itself in as the muon slows down.
|
||||
|
||||
wls.mac
|
||||
-This disables the main volume and enables the WLS slab volume. It sets the
|
||||
particle gun to use an e- to produce scintillation in the slab which will be
|
||||
absorbed by the WLS fibers and re-emited at a different wavelength.
|
||||
|
||||
vis.mac
|
||||
-This is a standard vis.mac file to tell the vis manager how to visualize the
|
||||
simulation.
|
||||
|
||||
photon.mac
|
||||
-A very simple test in which the gun is set to produce a single photon inside
|
||||
the main scintillator volume.
|
||||
|
||||
reviewEvent.mac
|
||||
-This is to review an event by loading in a random seed and running the event
|
||||
with verbose output. Modify the file to specify the filename of the random
|
||||
seed.
|
||||
|
||||
defaults.mac
|
||||
-This resets all values that can be changed with the /LXe/ commands back to
|
||||
their initial configuration including those that are not reset with
|
||||
/LXe/detector/defaults
|
||||
Reference in New Issue
Block a user