void AliITSMaterialsTGeo(TString gfile="geometry.root"){
// Macro to print out the ITS material definitions as found
// in the TGeo geometry file.
// retrives geometry
if(!gGeoManager) gGeoManager = new TGeoManager();
TGeoManager::Import(gfile.Data());
if (!gGeoManager) {
cout<<"geometry not found\n";
return;
} // end if
TList *medlist=gGeoManager->GetListOfMedia();
TGeoMedium *med;
TGeoMaterial *mat;
Int_t imed,nmed,i;
printf("imed Id Med_Name Mat_Name ");
for(i=0;i<20;i++) printf(" par[%2d] ",i);
printf("\n");
imed=0;
do{
med = (TGeoMedium*)(medlist->At(imed));
if(!med) continue;
/*if((((med->GetName())[0]=='I')&& // Only ITS.
((med->GetName())[1]=='T')&&
((med->GetName())[2]=='S')&&
((med->GetName())[3]=='_')))*/{
mat = med->GetMaterial();
if(mat)
printf("%4d %4d %30s %30s",imed,med->GetId(),med->GetName(),mat->GetName());
else
printf("%4d %4d %30s %30s",imed,med->GetId(),med->GetName(),"No Material");
for(i=0;i<20;i++) printf(" %12g",med->GetParam(i));
printf("\n");
imed++;
}
}while(med!=medlist->Last());
}
/**
* Calculate effective radiation length traversed by particle traveling between two points
* along straight line.
*
* Calculation is done according to the eq. (27.23)
* @see http://pdg.lbl.gov/2006/reviews/passagerpp.pdf
*
* @param globalPosStart starting point in the global coordinate system
* @param globalPosFinish ending point in the global coordinate system
* @param skipBoundaryVolumes if true subtract rad length of the volumes containing start and finish points
*
* @return radiation length in units of X0
*/
float EUTelGeometryTelescopeGeoDescription::findRadLengthIntegral( const double globalPosStart[], const double globalPosFinish[], bool skipBoundaryPonitsVolumes ) {
streamlog_out(DEBUG1) << "EUTelGeometryTelescopeGeoDescription::findRadLengthIntegral()" << std::endl;
float rad = 0.; // integral of radiation length in units of X0
const double mm2cm = 0.1;
/* TGeo uses cm and grams as internal units e.g. in radiation length and density. Telescope/LCIO uses mm. Therefore this routine is full of
annoying conversion factors */
const double stepLenght2 = ( globalPosFinish[0] - globalPosStart[0] )*( globalPosFinish[0] - globalPosStart[0] ) +
( globalPosFinish[1] - globalPosStart[1] )*( globalPosFinish[1] - globalPosStart[1] ) +
( globalPosFinish[2] - globalPosStart[2] )*( globalPosFinish[2] - globalPosStart[2] );
const double stepLenght = TMath::Sqrt( stepLenght2 );
// don't need conversion factor to for calculation of directions
const double xp = ( globalPosFinish[0] - globalPosStart[0] )/stepLenght;
const double yp = ( globalPosFinish[1] - globalPosStart[1] )/stepLenght;
const double zp = ( globalPosFinish[2] - globalPosStart[2] )/stepLenght;
streamlog_out(DEBUG0) << "Start point (x,y,z):" << globalPosStart[0] << "," << globalPosStart[1] << "," << globalPosStart[2] << std::endl;
streamlog_out(DEBUG0) << "Finish point (x,y,z):" << globalPosFinish[0] << "," << globalPosFinish[1] << "," << globalPosFinish[2] << std::endl;
streamlog_out(DEBUG0) << "Direction (nx,ny,nz):" << xp << "," << yp << "," << zp << std::endl;
double snext;
double pt[3], loc[3];
double epsil = 1.E-7;
double lastrad = 0.;
int ismall = 0;
int nbound = 0;
float length = 0.;
TGeoMedium *med;
TGeoShape *shape;
// Get starting node
gGeoManager->InitTrack( globalPosStart[0]/*mm*/, globalPosStart[1]/*mm*/, globalPosStart[2]/*mm*/, xp, yp, zp );
TGeoNode *nextnode = gGeoManager->GetCurrentNode( );
double currentStep = stepLenght /*mm*/;
// Loop over all, encountered during the propagation, volumes
while ( nextnode ) {
med = NULL;
// Check if current point is inside silicon sensor. Radiation length of silicon sensors is accounted in thin scatterers of GBL.
bool isBoundaryVolume = false;
if ( gGeoManager->IsSameLocation( globalPosStart[0], globalPosStart[1], globalPosStart[2] ) ||
gGeoManager->IsSameLocation( globalPosFinish[0], globalPosFinish[1], globalPosFinish[2] ) ) isBoundaryVolume = true;
if ( nextnode ) med = nextnode->GetVolume()->GetMedium();
else return 0.;
shape = nextnode->GetVolume()->GetShape();
// make a step to the next intersection point
if ( currentStep > 1.e-9 /*mm*/ ) nextnode = gGeoManager->FindNextBoundaryAndStep( currentStep /*mm*/ );
else return rad;
snext = gGeoManager->GetStep() /*mm*/;
// Small steps treatment
if ( snext < 1.e-8 /*mm*/ ) {
ismall++;
// Terminate calculation if too many small steps done
if ( ismall > 3 ) {
streamlog_out( WARNING1 ) << "ERROR: Small steps in: " << gGeoManager->GetPath() << " shape=" << shape->ClassName() << endl;
return rad;
}
// increase step size (epsilon) and advance along the particle direction
memcpy( pt, gGeoManager->GetCurrentPoint(), 3 * sizeof (double) );
const double *dir = gGeoManager->GetCurrentDirection();
for ( Int_t i = 0; i < 3; i++ ) pt[i] += epsil * dir[i];
snext = epsil;
length += snext;
// Ignore start and finish volumes if required
if ( skipBoundaryPonitsVolumes && isBoundaryVolume ) {
rad += 0.;
} else {
rad += lastrad*snext;
}
gGeoManager->CdTop( );
nextnode = gGeoManager->FindNode( pt[0], pt[1], pt[2] ); // Check if particle is crossed the boundary
if ( gGeoManager->IsOutside() ) return rad; // leave if not
TGeoMatrix *mat = gGeoManager->GetCurrentMatrix();
mat->MasterToLocal( pt, loc );
if ( !gGeoManager->GetCurrentVolume()->Contains( loc ) ) {
gGeoManager->CdUp();
nextnode = gGeoManager->GetCurrentNode(); // move to new volume
}
continue;
} else {
ismall = 0;
}
// Normal steps case
nbound++;
length += snext;
currentStep -= snext;
if ( med ) {
double radlen = med->GetMaterial()->GetRadLen() /*cm*/;
if ( radlen > 1.e-9 && radlen < 1.e10 ) {
lastrad = 1. / radlen * mm2cm;
// Ignore start and finish volumes if required
if ( skipBoundaryPonitsVolumes && isBoundaryVolume ) {
rad += 0.;
} else {
rad += lastrad*snext;
}
} else {
lastrad = 0.;
}
streamlog_out( DEBUG0 ) << "STEP #" << nbound << std::endl;
streamlog_out( DEBUG0 ) << " step[mm]=" << snext << " length[mm]=" << length
<< " rad[X0]=" << snext * mm2cm / radlen << " " << med->GetName( )
<< " rho[g/cm^3]=" << med->GetMaterial()->GetDensity() <<" radlen[cm]=" << radlen << " Boundary:" << (isBoundaryVolume?"yes":"no")
<< std::endl;
}
}
streamlog_out(DEBUG1) << "--------EUTelGeometryTelescopeGeoDescription::findRadLengthIntegral()--------" << std::endl;
return rad;
}
