Script supersceeded by AliForwarddNdetaTask.C and
[u/mrichter/AliRoot.git] / TPC / AliTPCExBConical.cxx
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ffab0c37 1/**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
3 * *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
6 * *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
15
16////////////////////////////////////////////////////////////////////////////
17// //
18// AliTPCExBConical class //
19// The class calculates the space point distortions due to the conical shape
20// of ALICE TPC:
21//
22// Becasue of mechanical deformation ALICE TPC, chambers are misaligned in z direction
23// TPC has roughly conical shape
24//
25// For the moment ONLY efective correction used - NOT EDGE EFFECT calcualted //
26// //
27// //
28// The class allows "effective Omega Tau" corrections. //
29//
30// //
31// date: 02/05/2010 //
32// Authors: Marian Ivanov, Jim Thomas, Magnus Mager, Stefan Rossegger //
33// //
34// Example usage: //
35// AliTPCExBConical conical; //
36// conical.SetOmegaTauT1T2(0.32,1.,1.); // values ideally from OCDB //
37// conical.SetXConical(0.001); // set conical in X direction (in rad) //
38// // plot dRPhi distortions ... //
39// conical.CreateHistoDRPhiinZR(1.,100,100)->Draw("surf2"); //
40////////////////////////////////////////////////////////////////////////////
534fd34a 41#include "AliMagF.h"
42#include "TGeoGlobalMagField.h"
43#include "AliTPCcalibDB.h"
44#include "AliTPCParam.h"
45#include "AliLog.h"
ffab0c37 46
47#include "TMath.h"
48#include "AliTPCROC.h"
49#include "AliTPCExBConical.h"
50ClassImp(AliTPCExBConical)
51
52AliTPCExBConical::AliTPCExBConical()
53 : AliTPCCorrection("exb_conical","ExB conical"),
54 fC1(0.),fC2(0.),fConicalFactor(0)
55{
56 //
57 // default constructor
58 //
59 for (Int_t i=0; i<3; i++){
60 fConicalA[i]= 0;
61 fConicalC[i]= 0;
62 }
63}
64
65AliTPCExBConical::~AliTPCExBConical() {
66 //
67 // default destructor
68 //
69}
70
534fd34a 71
72
ffab0c37 73void AliTPCExBConical::Init() {
74 //
534fd34a 75 // Initialization funtion
ffab0c37 76 //
77
534fd34a 78 AliMagF* magF= (AliMagF*)TGeoGlobalMagField::Instance()->GetField();
79 if (!magF) AliError("Magneticd field - not initialized");
80 Double_t bzField = magF->SolenoidField()/10.; //field in T
81 AliTPCParam *param= AliTPCcalibDB::Instance()->GetParameters();
82 if (!param) AliError("Parameters - not initialized");
83 Double_t vdrift = param->GetDriftV()/1000000.; // [cm/us] // From dataBase: to be updated: per second (ideally)
ffab0c37 84 Double_t ezField = 400; // [V/cm] // to be updated: never (hopefully)
85 Double_t wt = -10.0 * (bzField*10) * vdrift / ezField ;
ffab0c37 86 // Correction Terms for effective omegaTau; obtained by a laser calibration run
534fd34a 87 SetOmegaTauT1T2(wt,fT1,fT2);
ffab0c37 88
ffab0c37 89
90}
91
92void AliTPCExBConical::Update(const TTimeStamp &/*timeStamp*/) {
93 //
94 // Update function
95 //
534fd34a 96 AliMagF* magF= (AliMagF*)TGeoGlobalMagField::Instance()->GetField();
97 if (!magF) AliError("Magneticd field - not initialized");
98 Double_t bzField = magF->SolenoidField()/10.; //field in T
99 AliTPCParam *param= AliTPCcalibDB::Instance()->GetParameters();
100 if (!param) AliError("Parameters - not initialized");
101 Double_t vdrift = param->GetDriftV()/1000000.; // [cm/us] // From dataBase: to be updated: per second (ideally)
ffab0c37 102 Double_t ezField = 400; // [V/cm] // to be updated: never (hopefully)
103 Double_t wt = -10.0 * (bzField*10) * vdrift / ezField ;
ffab0c37 104 // Correction Terms for effective omegaTau; obtained by a laser calibration run
534fd34a 105 SetOmegaTauT1T2(wt,fT1,fT2);
106
ffab0c37 107
ffab0c37 108}
109
110
111
112void AliTPCExBConical::GetCorrection(const Float_t x[],const Short_t roc,Float_t dx[]) {
113 //
114 // Calculates the correction due conical shape
115 //
116 AliTPCROC * calROC = AliTPCROC::Instance();
117 const Double_t kRTPC0 =calROC->GetPadRowRadii(0,0);
118 const Double_t kRTPC1 =calROC->GetPadRowRadii(36,calROC->GetNRows(36)-1);
119 Float_t rmiddle=(kRTPC0+kRTPC1)/2.;
120 //
121 Double_t phi =TMath::ATan2(x[1],x[0]);
122 Double_t r =TMath::Sqrt(x[1]*x[1]+x[0]*x[0]);
123 Double_t dTheta=0;
124 if (roc%36<18) dTheta = fConicalA[0]+TMath::Cos(phi)*fConicalA[1]+TMath::Sin(phi)*fConicalA[2];
125 if (roc%36>=18) {
126 dTheta = fConicalC[0]+TMath::Cos(phi)*fConicalC[1]+TMath::Sin(phi)*fConicalC[2];
127 }
128 Double_t corr=dTheta*fConicalFactor;
129 if (roc%36>=18) corr*=-1.;
130 Double_t drphi=fC1*corr;
131 Double_t dr =fC2*corr;
132 dx[0]= TMath::Cos(phi)*dr-TMath::Sin(phi)*drphi;
133 dx[1]= TMath::Sin(phi)*dr+TMath::Cos(phi)*drphi;
be67055b 134 dx[2]= -0.001*dTheta*(r-rmiddle); // dtheta in mrad
ffab0c37 135
136}
137
b1f0a2a5 138void AliTPCExBConical::Print(const Option_t* option) const {
ffab0c37 139 //
140 // Print function to check the settings (e.g. the conical in the X direction)
141 // option=="a" prints the C0 and C1 coefficents for calibration purposes
142 //
143
144 TString opt = option; opt.ToLower();
534fd34a 145 printf("%s:%s\n",GetTitle(), GetName());
146 printf(" - T1: %1.4f, T2: %1.4f \n",fT1,fT2);
ffab0c37 147 printf("Conical settings: Empirical: %1.5f mm/mrad\n",fConicalFactor);
148 printf("Conical settings: A-Conical: %1.5f mrad:%1.5f mrad:%1.5f mrad \n",fConicalA[0],fConicalA[1],fConicalA[2]);
149 printf("Conical settings: C-Conical: %1.5f mrad:%1.5f mrad:%1.5f mrad \n",fConicalC[0],fConicalC[1],fConicalC[2]);
150
151}
152
153
154void AliTPCExBConical::SetConicalA(Float_t conicalA[3]){
155 //
156 // set paramters of conical shape - A side - obtained from alignment
157 //
158 fConicalA[0]= conicalA[0]; // constant
159 fConicalA[1]= conicalA[1]; // cos
160 fConicalA[2]= conicalA[2]; // sin
161}
162void AliTPCExBConical::SetConicalC(Float_t conicalC[3]){
163 //
164 // set paramters of conical shape -C side obtained form the alignemnt
165 //
166 fConicalC[0]= conicalC[0]; // constant
167 fConicalC[1]= conicalC[1]; // cos
168 fConicalC[2]= conicalC[2]; // sin
169}