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af26ce80 | 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 | /* $Id$ */ | |
17 | ||
18 | //////////////////////////////////////////////////////////////////////////// | |
19 | // // | |
20 | // Transforms clusters into space points with calibrated positions // | |
21 | // defined in the local tracking system // | |
22 | // // | |
23 | //////////////////////////////////////////////////////////////////////////// | |
24 | ||
25 | #include <TGeoMatrix.h> | |
26 | ||
27 | #include "AliLog.h" | |
28 | #include "AliTracker.h" | |
29 | #include "AliCodeTimer.h" | |
30 | ||
31 | #include "AliTRDtransform.h" | |
32 | #include "AliTRDcluster.h" | |
33 | #include "AliTRDgeometry.h" | |
34 | #include "AliTRDpadPlane.h" | |
35 | #include "AliTRDCommonParam.h" | |
36 | #include "AliTRDcalibDB.h" | |
37 | #include "Cal/AliTRDCalDet.h" | |
38 | #include "Cal/AliTRDCalROC.h" | |
39 | ||
40 | ClassImp(AliTRDtransform) | |
41 | ||
42 | //_____________________________________________________________________________ | |
43 | //AliTRDtransform::AliTRDtransform() | |
44 | // :AliTransform() | |
45 | AliTRDtransform::AliTRDtransform() | |
46 | :TObject() | |
47 | ,fGeo(0x0) | |
48 | ,fDetector(0) | |
49 | ,fParam(0x0) | |
50 | ,fCalibration(0x0) | |
51 | ,fCalVdriftROC(0x0) | |
52 | ,fCalT0ROC(0x0) | |
a60b4183 | 53 | ,fCalPRFROC(0x0) |
af26ce80 | 54 | ,fCalVdriftDet(0x0) |
55 | ,fCalT0Det(0x0) | |
56 | ,fCalVdriftDetValue(0) | |
57 | ,fCalT0DetValue(0) | |
58 | ,fSamplingFrequency(0) | |
59 | ,fPadPlane(0x0) | |
60 | ,fZShiftIdeal(0) | |
61 | ,fMatrix(0x0) | |
62 | { | |
63 | // | |
64 | // AliTRDtransform default constructor | |
65 | // | |
66 | ||
67 | } | |
68 | ||
69 | //_____________________________________________________________________________ | |
70 | //AliTRDtransform::AliTRDtransform(Int_t det) | |
71 | // :AliTransform() | |
72 | AliTRDtransform::AliTRDtransform(Int_t det) | |
73 | :TObject() | |
74 | ,fGeo(0x0) | |
75 | ,fDetector(0) | |
76 | ,fParam(0x0) | |
77 | ,fCalibration(0x0) | |
78 | ,fCalVdriftROC(0x0) | |
79 | ,fCalT0ROC(0x0) | |
a60b4183 | 80 | ,fCalPRFROC(0x0) |
af26ce80 | 81 | ,fCalVdriftDet(0x0) |
82 | ,fCalT0Det(0x0) | |
83 | ,fCalVdriftDetValue(0) | |
84 | ,fCalT0DetValue(0) | |
85 | ,fSamplingFrequency(0) | |
86 | ,fPadPlane(0x0) | |
87 | ,fZShiftIdeal(0) | |
88 | ,fMatrix(0x0) | |
89 | { | |
90 | // | |
91 | // AliTRDtransform constructor for a given detector | |
92 | // | |
93 | ||
94 | fGeo = new AliTRDgeometry(); | |
a938cf15 | 95 | if (!fGeo->CreateClusterMatrixArray()) { |
96 | AliError("Could not get transformation matrices\n"); | |
97 | } | |
af26ce80 | 98 | |
99 | fParam = AliTRDCommonParam::Instance(); | |
100 | if (!fParam) { | |
101 | AliError("Could not get common parameters\n"); | |
102 | } | |
103 | fSamplingFrequency = fParam->GetSamplingFrequency(); | |
104 | ||
105 | fCalibration = AliTRDcalibDB::Instance(); | |
106 | if (!fCalibration) { | |
107 | AliError("Cannot find calibration object"); | |
108 | } | |
109 | ||
110 | // Get the calibration objects for the global calibration | |
111 | fCalVdriftDet = fCalibration->GetVdriftDet(); | |
112 | fCalT0Det = fCalibration->GetT0Det(); | |
113 | ||
114 | SetDetector(det); | |
115 | ||
116 | } | |
117 | ||
118 | //_____________________________________________________________________________ | |
119 | //AliTRDtransform::AliTRDtransform(const AliTRDtransform &t) | |
120 | // :AliTransform(t) | |
121 | AliTRDtransform::AliTRDtransform(const AliTRDtransform &t) | |
122 | :TObject(t) | |
123 | ,fGeo(0x0) | |
124 | ,fDetector(t.fDetector) | |
125 | ,fParam(0x0) | |
126 | ,fCalibration(0x0) | |
127 | ,fCalVdriftROC(0x0) | |
128 | ,fCalT0ROC(0x0) | |
a60b4183 | 129 | ,fCalPRFROC(0x0) |
af26ce80 | 130 | ,fCalVdriftDet(0x0) |
131 | ,fCalT0Det(0x0) | |
132 | ,fCalVdriftDetValue(0) | |
133 | ,fCalT0DetValue(0) | |
134 | ,fSamplingFrequency(0) | |
135 | ,fPadPlane(0x0) | |
136 | ,fZShiftIdeal(0) | |
137 | ,fMatrix(0x0) | |
138 | { | |
139 | // | |
140 | // AliTRDtransform copy constructor | |
141 | // | |
142 | ||
143 | if (fGeo) { | |
144 | delete fGeo; | |
145 | } | |
146 | fGeo = new AliTRDgeometry(); | |
9a96f175 | 147 | fGeo->CreateClusterMatrixArray(); |
af26ce80 | 148 | |
149 | fParam = AliTRDCommonParam::Instance(); | |
150 | if (!fParam) { | |
151 | AliError("Could not get common parameters\n"); | |
152 | } | |
153 | fSamplingFrequency = fParam->GetSamplingFrequency(); | |
154 | ||
155 | fCalibration = AliTRDcalibDB::Instance(); | |
156 | if (!fCalibration) { | |
157 | AliError("Cannot find calibration object"); | |
158 | } | |
159 | fCalVdriftDet = fCalibration->GetVdriftDet(); | |
160 | fCalT0Det = fCalibration->GetT0Det(); | |
161 | ||
162 | } | |
163 | ||
164 | //_____________________________________________________________________________ | |
165 | AliTRDtransform::~AliTRDtransform() | |
166 | { | |
167 | // | |
168 | // AliTRDtransform destructor | |
169 | // | |
170 | ||
171 | if (fGeo) { | |
172 | delete fGeo; | |
173 | } | |
174 | ||
175 | } | |
176 | ||
177 | //_____________________________________________________________________________ | |
178 | void AliTRDtransform::SetDetector(Int_t det) | |
179 | { | |
180 | // | |
181 | // Set to a new detector number and update the calibration objects | |
182 | // and values accordingly | |
183 | // | |
184 | ||
185 | fDetector = det; | |
186 | ||
187 | // Get the calibration objects for the pad-by-pad calibration | |
188 | fCalVdriftROC = fCalibration->GetVdriftROC(det); | |
189 | fCalT0ROC = fCalibration->GetT0ROC(det); | |
a60b4183 | 190 | fCalPRFROC = fCalibration->GetPRFROC(det); |
af26ce80 | 191 | |
192 | // Get the detector wise defined calibration values | |
193 | fCalVdriftDetValue = fCalVdriftDet->GetValue(det); | |
194 | fCalT0DetValue = fCalT0Det->GetValue(det); | |
195 | ||
196 | // Shift needed to define Z-position relative to middle of chamber | |
053767a4 | 197 | Int_t layer = fGeo->GetLayer(det); |
198 | Int_t stack = fGeo->GetStack(det); | |
199 | fPadPlane = fGeo->GetPadPlane(layer,stack); | |
af26ce80 | 200 | fZShiftIdeal = 0.5 * (fPadPlane->GetRow0() + fPadPlane->GetRowEnd()); |
201 | ||
202 | // Get the current transformation matrix | |
9a96f175 | 203 | fMatrix = fGeo->GetClusterMatrix(det); |
af26ce80 | 204 | |
205 | } | |
206 | ||
207 | //_____________________________________________________________________________ | |
b72f4eaf | 208 | Bool_t AliTRDtransform::Transform(AliTRDcluster *c) |
af26ce80 | 209 | { |
210 | // | |
211 | // Transforms the local cluster coordinates into calibrated | |
212 | // space point positions defined in the local tracking system. | |
213 | // | |
214 | // Here the calibration for T0, Vdrift and ExB is applied as well. | |
215 | // | |
b72f4eaf | 216 | // Input: Cluster in the local chamber coordinates |
217 | // Output: Tracking cluster | |
af26ce80 | 218 | |
b72f4eaf | 219 | if (!fMatrix) return kFALSE; |
af26ce80 | 220 | |
af26ce80 | 221 | |
b72f4eaf | 222 | // Parameters to adjust the X position of clusters in the alignable volume |
ec3f0161 | 223 | const Double_t kX0shift = AliTRDgeometry::AnodePos(); //[cm] |
1814b374 | 224 | |
1814b374 | 225 | |
b72f4eaf | 226 | // Retrieve calibration values |
227 | Int_t col = c->GetPadCol(), row = c->GetPadRow(); | |
228 | // drift velocity | |
229 | Double_t vd = fCalVdriftDetValue * fCalVdriftROC->GetValue(col,row); | |
230 | // t0 | |
231 | Double_t t0 = fCalT0DetValue + fCalT0ROC->GetValue(col,row); | |
232 | // ExB correction | |
233 | Double_t exb = AliTRDCommonParam::Instance()->GetOmegaTau(vd); | |
234 | ||
235 | Float_t x = c->GetXloc(t0, vd); | |
236 | ||
237 | // pad response width with diffusion corrections | |
a60b4183 | 238 | Double_t s2 = fCalPRFROC->GetValue(col, row); s2 *= s2; |
17de99aa | 239 | Float_t dl, dt; |
240 | AliTRDCommonParam::Instance()->GetDiffCoeff(dl, dt, vd); | |
241 | s2 += dl*dl*x/(1.+2.*exb*exb); | |
b72f4eaf | 242 | s2 -= - 1.5e-1; |
243 | ||
244 | // Pad dimensions | |
245 | Double_t rs = fPadPlane->GetRowSize(row); | |
246 | Double_t cs = fPadPlane->GetColSize(col); | |
247 | Double_t y0 = fPadPlane->GetColPos(col) + .5*cs; | |
248 | Double_t loc[] = { | |
249 | kX0shift-x, // Invert the X-position, | |
250 | c->GetYloc(y0, s2, cs) - x*exb,// apply ExB correction | |
251 | fPadPlane->GetRowPos(row) - .5*rs - fZShiftIdeal // move the Z-position relative to the middle of the chamber | |
252 | }; | |
253 | ||
254 | // Go to tracking coordinates | |
255 | Double_t trk[3]; | |
256 | fMatrix->LocalToMaster(loc, trk); | |
257 | ||
258 | // store tracking values | |
259 | c->SetX(trk[0]);c->SetY(trk[1]);c->SetZ(trk[2]); | |
260 | c->SetSigmaY2(s2); | |
261 | c->SetSigmaZ2(fPadPlane->GetRowSize(row)*fPadPlane->GetRowSize(row)/12.); | |
262 | ||
263 | return kTRUE; | |
af26ce80 | 264 | } |
265 | ||
266 | //_____________________________________________________________________________ | |
267 | void AliTRDtransform::Recalibrate(AliTRDcluster *c, Bool_t setDet) | |
268 | { | |
269 | // | |
270 | // Recalibrates the position of a given cluster | |
271 | // If <setDet> is TRUE, the detector number is set for each cluster | |
272 | // automatically. Otherwise, AliTRDtransform::SetDetector() has to | |
273 | // be used. | |
274 | // | |
275 | ||
b72f4eaf | 276 | if (setDet) SetDetector(c->GetDetector()); |
277 | Transform(c); | |
af26ce80 | 278 | } |