/************************************************************************** * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. * * * * Author: The ALICE Off-line Project. * * Contributors are mentioned in the code where appropriate. * * * * Permission to use, copy, modify and distribute this software and its * * documentation strictly for non-commercial purposes is hereby granted * * without fee, provided that the above copyright notice appears in all * * copies and that both the copyright notice and this permission notice * * appear in the supporting documentation. The authors make no claims * * about the suitability of this software for any purpose. It is * * provided "as is" without express or implied warranty. * **************************************************************************/ ////////////////////////////////////////////////////////////////////////////// // // // AliTPCSpaceCharge3D class // // The class calculates the space point distortions due to a space charge // // effect .... // // Method of calculation: // // The analytical solution for the poisson problem in 3D (cylindrical coord)// // is used in form of look up tables. PieceOfCake (POC) voxel were pre- // // calculated and can be sumed up (weighted) according to the what is needed// // // // The class allows "effective Omega Tau" corrections. // // // // NOTE: This class is not capable of calculation z distortions due to // // drift velocity change in dependence of the electric field!!! // // // // date: 19/06/2010 // // Authors: Stefan Rossegger // // // // Example usage: // ////////////////////////////////////////////////////////////////////////////// #include "AliMagF.h" #include "TGeoGlobalMagField.h" #include "AliTPCcalibDB.h" #include "AliTPCParam.h" #include "AliLog.h" #include "TH2F.h" #include "TH3F.h" #include "TFile.h" #include "TVector.h" #include "TMatrix.h" #include "TMatrixD.h" #include "TMath.h" #include "AliTPCROC.h" #include "AliTPCSpaceCharge3D.h" ClassImp(AliTPCSpaceCharge3D) AliTPCSpaceCharge3D::AliTPCSpaceCharge3D() : AliTPCCorrection("SpaceCharge3D","Space Charge - 3D"), fC0(0.),fC1(0.), fCorrectionFactor(1.), fInitLookUp(kFALSE), fSCDataFileName((char*)"$(ALICE_ROOT)/TPC/Calib/maps/sc_3D_distribution_Sim.root"), fSCLookUpPOCsFileName((char*)"$(ALICE_ROOT)/TPC/Calib/maps/sc_3D_raw_18-18-26_17p-18p-25p-MN30.root") { // // default constructor // // Array which will contain the solution according to the setted charge density distribution // see InitSpaceCharge3DDistortion() function for ( Int_t k = 0 ; k < kNPhi ; k++ ) { fLookUpErOverEz[k] = new TMatrixD(kNR,kNZ); fLookUpEphiOverEz[k] = new TMatrixD(kNR,kNZ); fLookUpDeltaEz[k] = new TMatrixD(kNR,kNZ); fSCdensityDistribution[k] = new TMatrixD(kNR,kNZ); } printf("%s\n",fSCDataFileName); printf("%s\n",fSCLookUpPOCsFileName); SetSCDataFileName(fSCDataFileName); } AliTPCSpaceCharge3D::~AliTPCSpaceCharge3D() { // // default destructor // for ( Int_t k = 0 ; k < kNPhi ; k++ ) { delete fLookUpErOverEz[k]; delete fLookUpEphiOverEz[k]; delete fLookUpDeltaEz[k]; delete fSCdensityDistribution[k]; } // delete fSCdensityDistribution; } void AliTPCSpaceCharge3D::Init() { // // Initialization funtion // AliMagF* magF= (AliMagF*)TGeoGlobalMagField::Instance()->GetField(); if (!magF) AliError("Magneticd field - not initialized"); Double_t bzField = magF->SolenoidField()/10.; //field in T AliTPCParam *param= AliTPCcalibDB::Instance()->GetParameters(); if (!param) AliError("Parameters - not initialized"); Double_t vdrift = param->GetDriftV()/1000000.; // [cm/us] // From dataBase: to be updated: per second (ideally) Double_t ezField = 400; // [V/cm] // to be updated: never (hopefully) Double_t wt = -10.0 * (bzField*10) * vdrift / ezField ; // Correction Terms for effective omegaTau; obtained by a laser calibration run SetOmegaTauT1T2(wt,fT1,fT2); InitSpaceCharge3DDistortion(); // fill the look up table } void AliTPCSpaceCharge3D::Update(const TTimeStamp &/*timeStamp*/) { // // Update function // AliMagF* magF= (AliMagF*)TGeoGlobalMagField::Instance()->GetField(); if (!magF) AliError("Magneticd field - not initialized"); Double_t bzField = magF->SolenoidField()/10.; //field in T AliTPCParam *param= AliTPCcalibDB::Instance()->GetParameters(); if (!param) AliError("Parameters - not initialized"); Double_t vdrift = param->GetDriftV()/1000000.; // [cm/us] // From dataBase: to be updated: per second (ideally) Double_t ezField = 400; // [V/cm] // to be updated: never (hopefully) Double_t wt = -10.0 * (bzField*10) * vdrift / ezField ; // Correction Terms for effective omegaTau; obtained by a laser calibration run SetOmegaTauT1T2(wt,fT1,fT2); // SetCorrectionFactor(1.); // should come from some database } void AliTPCSpaceCharge3D::GetCorrection(const Float_t x[],const Short_t roc,Float_t dx[]) { // // Calculates the correction due the Space Charge effect within the TPC drift volume // if (!fInitLookUp) { AliInfo("Lookup table was not initialized! Performing the inizialisation now ..."); InitSpaceCharge3DDistortion(); } Int_t order = 1 ; // FIXME: hardcoded? Linear interpolation = 1, Quadratic = 2 Double_t intEr, intEphi, intdEz ; Double_t r, phi, z ; Int_t sign; r = TMath::Sqrt( x[0]*x[0] + x[1]*x[1] ) ; phi = TMath::ATan2(x[1],x[0]) ; if ( phi < 0 ) phi += TMath::TwoPi() ; // Table uses phi from 0 to 2*Pi z = x[2] ; // Create temporary copy of x[2] if ( (roc%36) < 18 ) { sign = 1; // (TPC A side) } else { sign = -1; // (TPC C side) } if ( sign==1 && z < fgkZOffSet ) z = fgkZOffSet; // Protect against discontinuity at CE if ( sign==-1 && z > -fgkZOffSet ) z = -fgkZOffSet; // Protect against discontinuity at CE if ( (sign==1 && z<0) || (sign==-1 && z>0) ) // just a consistency check AliError("ROC number does not correspond to z coordinate! Calculation of distortions is most likely wrong!"); // Get the Er and Ephi field integrals plus the integral over DeltaEz intEr = Interpolate3DTable(order, r, z, phi, kNR, kNZ, kNPhi, fgkRList, fgkZList, fgkPhiList, fLookUpErOverEz ); intEphi = Interpolate3DTable(order, r, z, phi, kNR, kNZ, kNPhi, fgkRList, fgkZList, fgkPhiList, fLookUpEphiOverEz); intdEz = Interpolate3DTable(order, r, z, phi, kNR, kNZ, kNPhi, fgkRList, fgkZList, fgkPhiList, fLookUpDeltaEz ); // Calculate distorted position if ( r > 0.0 ) { phi = phi + fCorrectionFactor *( fC0*intEphi - fC1*intEr ) / r; r = r + fCorrectionFactor *( fC0*intEr + fC1*intEphi ); } Double_t dz = intdEz * fCorrectionFactor * fgkdvdE; // Calculate correction in cartesian coordinates dx[0] = r * TMath::Cos(phi) - x[0]; dx[1] = r * TMath::Sin(phi) - x[1]; dx[2] = dz; // z distortion - (scaled with driftvelocity dependency on the Ez field and the overall scaling factor) } void AliTPCSpaceCharge3D::InitSpaceCharge3DDistortion() { // // Initialization of the Lookup table which contains the solutions of the // "space charge" (poisson) problem // // The sum-up uses a look-up table which contains different discretized Space charge fields // in order to calculate the corresponding field deviations due to a given (discretized) // space charge distribution .... // // Method of calculation: Weighted sum up of the different fields within the look up table // if (fInitLookUp) { AliInfo("Lookup table was already initialized!"); // return; } AliInfo("Preparation of the weighted look-up table"); TFile *f = new TFile(fSCLookUpPOCsFileName); if (!f) { AliError("Precalculated POC-looup-table could not be found"); return; } // units are in [m] TVector *gridf = (TVector*) f->Get("constants"); TVector &grid = *gridf; TMatrix *coordf = (TMatrix*) f->Get("coordinates"); TMatrix &coord = *coordf; TMatrix *coordPOCf = (TMatrix*) f->Get("POCcoord"); TMatrix &coordPOC = *coordPOCf; Bool_t flagRadSym = 0; if (grid(1)==1 && grid(4)==1) { AliInfo("LOOK UP TABLE IS RADIAL SYMETTRIC - Field in Phi is ZERO"); flagRadSym=1; } Int_t rows = (Int_t)grid(0); // number of points in r direction Int_t phiSlices = (Int_t)grid(1); // number of points in phi Int_t columns = (Int_t)grid(2); // number of points in z direction const Float_t gridSizeR = grid(6)*100; // unit in [cm] const Float_t gridSizePhi = grid(7); // unit in [rad] const Float_t gridSizeZ = grid(8)*100; // unit in [cm] // temporary matrices needed for the calculation TMatrixD *arrayofErA[phiSlices], *arrayofEphiA[phiSlices], *arrayofdEzA[phiSlices]; TMatrixD *arrayofErC[phiSlices], *arrayofEphiC[phiSlices], *arrayofdEzC[phiSlices]; TMatrixD *arrayofEroverEzA[phiSlices], *arrayofEphioverEzA[phiSlices], *arrayofDeltaEzA[phiSlices]; TMatrixD *arrayofEroverEzC[phiSlices], *arrayofEphioverEzC[phiSlices], *arrayofDeltaEzC[phiSlices]; for ( Int_t k = 0 ; k < phiSlices ; k++ ) { arrayofErA[k] = new TMatrixD(rows,columns) ; arrayofEphiA[k] = new TMatrixD(rows,columns) ; // zero if radial symmetric arrayofdEzA[k] = new TMatrixD(rows,columns) ; arrayofErC[k] = new TMatrixD(rows,columns) ; arrayofEphiC[k] = new TMatrixD(rows,columns) ; // zero if radial symmetric arrayofdEzC[k] = new TMatrixD(rows,columns) ; arrayofEroverEzA[k] = new TMatrixD(rows,columns) ; arrayofEphioverEzA[k] = new TMatrixD(rows,columns) ; // zero if radial symmetric arrayofDeltaEzA[k] = new TMatrixD(rows,columns) ; arrayofEroverEzC[k] = new TMatrixD(rows,columns) ; arrayofEphioverEzC[k] = new TMatrixD(rows,columns) ; // zero if radial symmetric arrayofDeltaEzC[k] = new TMatrixD(rows,columns) ; // Set the values to zero the lookup tables // not necessary, it is done in the constructor of TMatrix - code deleted } // list of points as used in the interpolation (during sum up) Double_t rlist[rows], zedlist[columns] , philist[phiSlices]; for ( Int_t k = 0 ; k < phiSlices ; k++ ) { philist[k] = gridSizePhi * k; for ( Int_t i = 0 ; i < rows ; i++ ) { rlist[i] = fgkIFCRadius + i*gridSizeR ; for ( Int_t j = 0 ; j < columns ; j++ ) { zedlist[j] = j * gridSizeZ ; } } } // only done once // Prepare summation Vectors // Int_t numPosInd = (Int_t)(grid(0)*grid(1)*grid(2)); // Number of fulcrums in the look-up table // Int_t numPOC = (Int_t)(grid(3)*grid(4)*grid(5)); // Number of POC conf. in the look-up table TTree *treePOC = (TTree*)f->Get("POCall"); TVector *bEr = 0; TVector *bEphi= 0; TVector *bEz = 0; treePOC->SetBranchAddress("Er",&bEr); if (!flagRadSym) treePOC->SetBranchAddress("Ephi",&bEphi); treePOC->SetBranchAddress("Ez",&bEz); /* TBranch *b2Er = treePOC->GetBranch("Er"); TBranch *b2Ephi =0; if (!flagRadSym) b2Ephi = treePOC->GetBranch("Ephi"); TBranch *b2Ez = treePOC->GetBranch("Ez"); */ // Read the complete tree and do a weighted sum-up over the POC configurations // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Int_t treeNumPOC = (Int_t)treePOC->GetEntries(); // Number of POC conf. in the look-up table Int_t ipC = 0; // POC Conf. counter (note: different to the POC number in the tree!) for (Int_t itreepC=0; itreepCGetEntry(itreepC); /* b2Er->GetEntry(itreepC); if (!flagRadSym) b2Ephi->GetEntry(itreepC); b2Ez->GetEntry(itreepC); */ // center of the POC voxel in [meter] Double_t r0 = coordPOC(ipC,0); Double_t phi0 = coordPOC(ipC,1); Double_t z0 = coordPOC(ipC,2); ipC++; // POC conf. counter // weights (charge density) at POC position on the A and C side (in C/m^3/e0) // note: coordinates are in [cm] Double_t weightA = GetSpaceChargeDensity(r0*100,phi0, z0*100); Double_t weightC = GetSpaceChargeDensity(r0*100,phi0,-z0*100); // Summing up the vector components according to their weight Int_t ip = 0; for ( Int_t j = 0 ; j < columns ; j++ ) { for ( Int_t i = 0 ; i < rows ; i++ ) { for ( Int_t k = 0 ; k < phiSlices ; k++ ) { // check wether the coordinates were screwed if ((coord(0,ip)*100-rlist[i])>0.01 || (coord(1,ip)-philist[k])>0.01 || (coord(2,ip)*100-zedlist[j])>0.01) { AliError("internal error: coordinate system was screwed during the sum-up"); printf("lookup: (r,phi,z)=(%lf,%lf,%lf)\n",coord(0,ip)*100,coord(1,ip),coord(2,ip)*100); printf("sum-up: (r,phi,z)=(%lf,%lf,%lf)\n",rlist[i],philist[k],zedlist[j]); AliError("Don't trust the results of the space charge calibration!"); } // unfortunately, the lookup tables were produced to be faster for phi symmetric charges // This will be the most frequent usage (hopefully) // That's why we have to do this here ... TMatrixD &erA = *arrayofErA[k] ; TMatrixD &ephiA = *arrayofEphiA[k]; TMatrixD &dEzA = *arrayofdEzA[k] ; TMatrixD &erC = *arrayofErC[k] ; TMatrixD &ephiC = *arrayofEphiC[k]; TMatrixD &dEzC = *arrayofdEzC[k] ; // Sum up - Efield values in [V/m] -> transition to [V/cm] erA(i,j) += ((*bEr)(ip)) * weightA /100; erC(i,j) += ((*bEr)(ip)) * weightC /100; if (!flagRadSym) { ephiA(i,j) += ((*bEphi)(ip)) * weightA; // [V/rad] ephiC(i,j) += ((*bEphi)(ip)) * weightC; // [V/rad] } dEzA(i,j) += ((*bEz)(ip)) * weightA /100; dEzC(i,j) += ((*bEz)(ip)) * weightC /100; // increase the counter ip++; } } } // Rotation and summation in the rest of the dPhiSteps // which were not stored in the tree due to storage & symmetry reasons Int_t phiPoints = (Int_t) grid(1); Int_t phiPOC = (Int_t) grid(4); // printf("%d %d\n",phiPOC,flagRadSym); for (Int_t phiiC = 1; phiiC=rotVal) { ipR = ip-rotVal; } else { ipR = ip+(phiPoints-rotVal); } // unfortunately, the lookup tables were produced to be faster for phi symmetric charges // This will be the most frequent usage (hopefully) // That's why we have to do this here and not outside the loop ... TMatrixD &erA = *arrayofErA[k] ; TMatrixD &ephiA = *arrayofEphiA[k]; TMatrixD &dEzA = *arrayofdEzA[k] ; TMatrixD &erC = *arrayofErC[k] ; TMatrixD &ephiC = *arrayofEphiC[k]; TMatrixD &dEzC = *arrayofdEzC[k] ; // Sum up - Efield values in [V/m] -> transition to [V/cm] erA(i,j) += ((*bEr)(ipR)) * weightA /100; erC(i,j) += ((*bEr)(ipR)) * weightC /100; if (!flagRadSym) { ephiA(i,j) += ((*bEphi)(ipR)) * weightA; // [V/rad] ephiC(i,j) += ((*bEphi)(ipR)) * weightC; // [V/rad] } dEzA(i,j) += ((*bEz)(ipR)) * weightA /100; dEzC(i,j) += ((*bEz)(ipR)) * weightC /100; // increase the counter ip++; } } } // end coordinate loop } // end phi-POC summation (phiiC) // printf("POC: (r,phi,z) = (%lf %lf %lf) | weight(A,C): %03.1lf %03.1lf\n",r0,phi0,z0, weightA, weightC); } // end POC loop AliInfo("Division and integration"); // ------------------------------------------------------------------------------- // Division by the Ez (drift) field and integration along z Double_t ezField = (fgkCathodeV-fgkGG)/fgkTPCZ0; // = Electric Field (V/cm) Magnitude ~ -400 V/cm; for ( Int_t k = 0 ; k < phiSlices ; k++ ) { // phi loop // matrices holding the solution - summation of POC charges TMatrixD &erA = *arrayofErA[k] ; TMatrixD &ephiA = *arrayofEphiA[k]; TMatrixD &dezA = *arrayofdEzA[k] ; TMatrixD &erC = *arrayofErC[k] ; TMatrixD &ephiC = *arrayofEphiC[k]; TMatrixD &dezC = *arrayofdEzC[k] ; // matrices which contain the integrated fields (divided by the drift field) TMatrixD &erOverEzA = *arrayofEroverEzA[k] ; TMatrixD &ephiOverEzA = *arrayofEphioverEzA[k]; TMatrixD &deltaEzA = *arrayofDeltaEzA[k]; TMatrixD &erOverEzC = *arrayofEroverEzC[k] ; TMatrixD &ephiOverEzC = *arrayofEphioverEzC[k]; TMatrixD &deltaEzC = *arrayofDeltaEzC[k]; for ( Int_t i = 0 ; i < rows ; i++ ) { // r loop for ( Int_t j = columns-1 ; j >= 0 ; j-- ) {// z loop // Count backwards to facilitate integration over Z Int_t index = 1 ; // Simpsons rule if N=odd.If N!=odd then add extra point by trapezoidal rule. erOverEzA(i,j) = 0; ephiOverEzA(i,j) = 0; deltaEzA(i,j) = 0; erOverEzC(i,j) = 0; ephiOverEzC(i,j) = 0; deltaEzC(i,j) = 0; for ( Int_t m = j ; m < columns ; m++ ) { // integration erOverEzA(i,j) += index*(gridSizeZ/3.0)*erA(i,m)/(-1*ezField) ; erOverEzC(i,j) += index*(gridSizeZ/3.0)*erC(i,m)/(-1*ezField) ; if (!flagRadSym) { ephiOverEzA(i,j) += index*(gridSizeZ/3.0)*ephiA(i,m)/(-1*ezField) ; ephiOverEzC(i,j) += index*(gridSizeZ/3.0)*ephiC(i,m)/(-1*ezField) ; } deltaEzA(i,j) += index*(gridSizeZ/3.0)*dezA(i,m) ; deltaEzC(i,j) += index*(gridSizeZ/3.0)*dezC(i,m) ; if ( index != 4 ) index = 4; else index = 2 ; } if ( index == 4 ) { erOverEzA(i,j) -= (gridSizeZ/3.0)*erA(i,columns-1)/(-1*ezField) ; erOverEzC(i,j) -= (gridSizeZ/3.0)*erC(i,columns-1)/(-1*ezField) ; if (!flagRadSym) { ephiOverEzA(i,j) -= (gridSizeZ/3.0)*ephiA(i,columns-1)/(-1*ezField) ; ephiOverEzC(i,j) -= (gridSizeZ/3.0)*ephiC(i,columns-1)/(-1*ezField) ; } deltaEzA(i,j) -= (gridSizeZ/3.0)*dezA(i,columns-1) ; deltaEzC(i,j) -= (gridSizeZ/3.0)*dezC(i,columns-1) ; } if ( index == 2 ) { erOverEzA(i,j) += (gridSizeZ/3.0)*(0.5*erA(i,columns-2)-2.5*erA(i,columns-1))/(-1*ezField) ; erOverEzC(i,j) += (gridSizeZ/3.0)*(0.5*erC(i,columns-2)-2.5*erC(i,columns-1))/(-1*ezField) ; if (!flagRadSym) { ephiOverEzA(i,j) += (gridSizeZ/3.0)*(0.5*ephiA(i,columns-2)-2.5*ephiA(i,columns-1))/(-1*ezField) ; ephiOverEzC(i,j) += (gridSizeZ/3.0)*(0.5*ephiC(i,columns-2)-2.5*ephiC(i,columns-1))/(-1*ezField) ; } deltaEzA(i,j) += (gridSizeZ/3.0)*(0.5*dezA(i,columns-2)-2.5*dezA(i,columns-1)) ; deltaEzC(i,j) += (gridSizeZ/3.0)*(0.5*dezC(i,columns-2)-2.5*dezC(i,columns-1)) ; } if ( j == columns-2 ) { erOverEzA(i,j) = (gridSizeZ/3.0)*(1.5*erA(i,columns-2)+1.5*erA(i,columns-1))/(-1*ezField) ; erOverEzC(i,j) = (gridSizeZ/3.0)*(1.5*erC(i,columns-2)+1.5*erC(i,columns-1))/(-1*ezField) ; if (!flagRadSym) { ephiOverEzA(i,j) = (gridSizeZ/3.0)*(1.5*ephiA(i,columns-2)+1.5*ephiA(i,columns-1))/(-1*ezField) ; ephiOverEzC(i,j) = (gridSizeZ/3.0)*(1.5*ephiC(i,columns-2)+1.5*ephiC(i,columns-1))/(-1*ezField) ; } deltaEzA(i,j) = (gridSizeZ/3.0)*(1.5*dezA(i,columns-2)+1.5*dezA(i,columns-1)) ; deltaEzC(i,j) = (gridSizeZ/3.0)*(1.5*dezC(i,columns-2)+1.5*dezC(i,columns-1)) ; } if ( j == columns-1 ) { erOverEzA(i,j) = 0; erOverEzC(i,j) = 0; if (!flagRadSym) { ephiOverEzA(i,j) = 0; ephiOverEzC(i,j) = 0; } deltaEzA(i,j) = 0; deltaEzC(i,j) = 0; } } } } AliInfo("Interpolation to Standard grid"); // ------------------------------------------------------------------------------- // Interpolate results onto the standard grid which is used for all AliTPCCorrections const Int_t order = 1 ; // Linear interpolation = 1, Quadratic = 2 Double_t r, phi, z ; for ( Int_t k = 0 ; k < kNPhi ; k++ ) { phi = fgkPhiList[k] ; TMatrixD &erOverEz = *fLookUpErOverEz[k] ; TMatrixD &ephiOverEz = *fLookUpEphiOverEz[k]; TMatrixD &deltaEz = *fLookUpDeltaEz[k] ; for ( Int_t j = 0 ; j < kNZ ; j++ ) { z = TMath::Abs(fgkZList[j]) ; // z position is symmetric for ( Int_t i = 0 ; i < kNR ; i++ ) { r = fgkRList[i] ; // Interpolate Lookup tables onto standard grid if (fgkZList[j]>0) { erOverEz(i,j) = Interpolate3DTable(order, r, z, phi, rows, columns, phiSlices, rlist, zedlist, philist, arrayofEroverEzA ); ephiOverEz(i,j) = Interpolate3DTable(order, r, z, phi, rows, columns, phiSlices, rlist, zedlist, philist, arrayofEphioverEzA); deltaEz(i,j) = Interpolate3DTable(order, r, z, phi, rows, columns, phiSlices, rlist, zedlist, philist, arrayofDeltaEzA ); } else { erOverEz(i,j) = Interpolate3DTable(order, r, z, phi, rows, columns, phiSlices, rlist, zedlist, philist, arrayofEroverEzC ); ephiOverEz(i,j) = Interpolate3DTable(order, r, z, phi, rows, columns, phiSlices, rlist, zedlist, philist, arrayofEphioverEzC); deltaEz(i,j) = - Interpolate3DTable(order, r, z, phi, rows, columns, phiSlices, rlist, zedlist, philist, arrayofDeltaEzC ); // negative coordinate system on C side } } // end r loop } // end z loop } // end phi loop // clear the temporary arrays lists for ( Int_t k = 0 ; k < phiSlices ; k++ ) { delete arrayofErA[k]; delete arrayofEphiA[k]; delete arrayofdEzA[k]; delete arrayofErC[k]; delete arrayofEphiC[k]; delete arrayofdEzC[k]; delete arrayofEroverEzA[k]; delete arrayofEphioverEzA[k]; delete arrayofDeltaEzA[k]; delete arrayofEroverEzC[k]; delete arrayofEphioverEzC[k]; delete arrayofDeltaEzC[k]; } fInitLookUp = kTRUE; } void AliTPCSpaceCharge3D::SetSCDataFileName(char *const fname) { // // Set & load the Space charge density distribution from a file // (linear interpolation onto a standard grid) // fSCDataFileName = fname; TFile *f = new TFile(fSCDataFileName,"READ"); if (!f) { AliError(Form("File %s, which should contain the space charge distribution, could not be found", fSCDataFileName)); return; } TH3F *density = (TH3F*) f->Get("SpaceChargeDistribution"); if (!density) { AliError(Form("The indicated file (%s) does not contain a histogram called %s", fSCDataFileName,"SpaceChargeDistribution")); return; } Double_t r, phi, z ; for ( Int_t k = 0 ; k < kNPhi ; k++ ) { phi = fgkPhiList[k] ; TMatrixD &scdensity = *fSCdensityDistribution[k] ; for ( Int_t j = 0 ; j < kNZ ; j++ ) { z = TMath::Abs(fgkZList[j]) ; // z position is symmetric for ( Int_t i = 0 ; i < kNR ; i++ ) { r = fgkRList[i] ; scdensity(i,j) = density->Interpolate(r,phi,z); // quite slow // printf("%lf %lf %lf: %lf\n",r,phi,z,scdensity(i,j)); } } } f->Close(); fInitLookUp = kFALSE; } Float_t AliTPCSpaceCharge3D::GetSpaceChargeDensity(Float_t r, Float_t phi, Float_t z) { // // returns the (input) space charge density at a given point according // Note: input in [cm], output in [C/m^3/e0] !! // if (!fSCdensityDistribution) { printf("Scheiss is nuul - argg\n"); return 0.; } while (phi<0) phi += TMath::TwoPi(); while (phi>TMath::TwoPi()) phi -= TMath::TwoPi(); // Float_t sc =fSCdensityDistribution->Interpolate(r0,phi0,z0); Int_t order = 1; // Float_t sc = Interpolate3DTable(order, r, z, phi, kNR, kNZ, kNPhi, fgkRList, fgkZList, fgkPhiList, fSCdensityDistribution ); // printf("%lf %lf %lf: %lf\n",r,phi,z,sc); return sc; } TH2F * AliTPCSpaceCharge3D::CreateHistoSCinXY(Float_t z, Int_t nx, Int_t ny) { // // return a simple histogramm containing the space charge distribution (input for the calculation) // TH2F *h=CreateTH2F("spaceCharge",GetTitle(),"x [cm]","y [cm]","#rho_{sc} [C/m^{3}/e_{0}]", nx,-250.,250.,ny,-250.,250.); for (Int_t iy=1;iy<=ny;++iy) { Double_t yp = h->GetYaxis()->GetBinCenter(iy); for (Int_t ix=1;ix<=nx;++ix) { Double_t xp = h->GetXaxis()->GetBinCenter(ix); Float_t r = TMath::Sqrt(xp*xp+yp*yp); Float_t phi = TMath::ATan2(yp,xp); if (85.<=r && r<=250.) { Float_t sc = GetSpaceChargeDensity(r,phi,z)/fgke0; // in [C/m^3/e0] h->SetBinContent(ix,iy,sc); } else { h->SetBinContent(ix,iy,0.); } } } return h; } TH2F * AliTPCSpaceCharge3D::CreateHistoSCinZR(Float_t phi, Int_t nz, Int_t nr) { // // return a simple histogramm containing the space charge distribution (input for the calculation) // TH2F *h=CreateTH2F("spaceCharge",GetTitle(),"z [cm]","r [cm]","#rho_{sc} [C/m^{3}/e_{0}]", nz,-250.,250.,nr,85.,250.); for (Int_t ir=1;ir<=nr;++ir) { Float_t r = h->GetYaxis()->GetBinCenter(ir); for (Int_t iz=1;iz<=nz;++iz) { Float_t z = h->GetXaxis()->GetBinCenter(iz); Float_t sc = GetSpaceChargeDensity(r,phi,z)/fgke0; // in [C/m^3/e0] h->SetBinContent(iz,ir,sc); } } return h; } void AliTPCSpaceCharge3D::WriteChargeDistributionToFile(const char* fname) { // // Example on how to write a Space charge distribution into a File // (see below: estimate from scaling STAR measurements to Alice) // TFile *f = new TFile(fname,"RECREATE"); // some grid, not too course Int_t nr = 72; Int_t nphi = 180; Int_t nz = 250; Double_t dr = (fgkOFCRadius-fgkIFCRadius)/(nr+1); Double_t dphi = TMath::TwoPi()/(nphi+1); Double_t dz = 500./(nz+1); Double_t safty = 0.; // due to a root bug which does not interpolate the boundary (first and last bin) correctly TH3F *histo = new TH3F("charge","charge", nr,fgkIFCRadius-dr-safty,fgkOFCRadius+dr+safty, nphi,0-dphi-safty,TMath::TwoPi()+dphi+safty, nz,-250-dz-safty,250+dz+safty); for (Int_t ir=1;ir<=nr;++ir) { Double_t rp = histo->GetXaxis()->GetBinCenter(ir); for (Int_t iphi=1;iphi<=nphi;++iphi) { Double_t phip = histo->GetYaxis()->GetBinCenter(iphi); for (Int_t iz=1;iz<=nz;++iz) { Double_t zp = histo->GetZaxis()->GetBinCenter(iz); zp = TMath::Abs(zp); // symmetric on both sides of the TPC // recalculation to meter Double_t lZ = 2.5; // approx. TPC drift length Double_t rpM = rp/100.; // in [m] Double_t zpM = zp/100.; // in [m] // setting of mb multiplicity and Interaction rate Double_t multiplicity = 950; Double_t intRate = 8000; // calculation of "scaled" parameters Double_t a = multiplicity*intRate/79175; Double_t b = a/lZ; Double_t charge = (a - b * zpM)/(rpM*rpM); // charge in [C/m^3/e0] // some 'arbitrary' GG leaks if ( (phip<(TMath::Pi()/9*3) && phip>(TMath::Pi()/9*2) ) ) { //|| // (phip<(TMath::Pi()/9*7) && phip>(TMath::Pi()/9*6) ) || // (phip<(TMath::Pi()/9*16) && phip>(TMath::Pi()/9*13) ) ){ if (rp>130&&rp<135) charge = 300; } // printf("%lf %lf %lf: %lf\n",rp,phip,zp,charge); charge = charge*fgke0; // [C/m^3] histo->SetBinContent(ir,iphi,iz,charge); } } } histo->Write("SpaceChargeDistribution"); f->Close(); } void AliTPCSpaceCharge3D::Print(const Option_t* option) const { // // Print function to check the settings of the boundary vectors // option=="a" prints the C0 and C1 coefficents for calibration purposes // TString opt = option; opt.ToLower(); printf("%s\n",GetTitle()); printf(" - Space Charge effect with arbitrary 3D charge density (as input).\n"); printf(" SC correction factor: %f \n",fCorrectionFactor); if (opt.Contains("a")) { // Print all details printf(" - T1: %1.4f, T2: %1.4f \n",fT1,fT2); printf(" - C1: %1.4f, C0: %1.4f \n",fC1,fC0); } if (!fInitLookUp) AliError("Lookup table was not initialized! You should do InitSpaceCharge3DDistortion() ..."); }