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5e86ff99 | 1 | #include <stdio.h> |
2 | ||
3 | #include "TMath.h" | |
4 | ||
5 | #include "AliTRDltuParam.h" | |
6 | ||
7 | // definition of geometry constants | |
8 | Float_t AliTRDltuParam::fgZrow[6][5] = { | |
9 | {301, 177, 53, -57, -181}, | |
10 | {301, 177, 53, -57, -181}, | |
11 | {315, 184, 53, -57, -188}, | |
12 | {329, 191, 53, -57, -195}, | |
13 | {343, 198, 53, -57, -202}, | |
14 | {347, 200, 53, -57, -204}}; | |
15 | Float_t AliTRDltuParam::fgX[6] = | |
16 | {300.65, 313.25, 325.85, 338.45, 351.05, 363.65}; | |
17 | Float_t AliTRDltuParam::fgTiltingAngle[6] = | |
18 | {-2., 2., -2., 2., -2., 2.}; | |
19 | Int_t AliTRDltuParam::fgDyMax = 63; | |
20 | Int_t AliTRDltuParam::fgDyMin = -64; | |
1fa993c2 | 21 | Float_t AliTRDltuParam::fgBinDy = 140e-4; |
5e86ff99 | 22 | Float_t AliTRDltuParam::fgWidthPad[6] = |
23 | {0.635, 0.665, 0.695, 0.725, 0.755, 0.785}; | |
24 | Float_t AliTRDltuParam::fgLengthInnerPadC1[6] = | |
25 | {7.5, 7.5, 8.0, 8.5, 9.0, 9.0}; | |
26 | Float_t AliTRDltuParam::fgLengthOuterPadC1[6] = | |
27 | {7.5, 7.5, 7.5, 7.5, 7.5, 8.5}; | |
28 | Float_t AliTRDltuParam::fgLengthInnerPadC0 = 9.0; | |
29 | Float_t AliTRDltuParam::fgLengthOuterPadC0 = 8.0; | |
30 | Float_t AliTRDltuParam::fgScalePad = 256. * 32.; | |
918cceaa | 31 | Float_t AliTRDltuParam::fgDriftLength = 3.; |
5e86ff99 | 32 | |
33 | AliTRDltuParam::AliTRDltuParam() : | |
34 | TObject(), | |
35 | fMagField(0.), | |
36 | fOmegaTau(0.), | |
37 | fPtMin(0.1), | |
38 | fNtimebins(20 << 5), | |
51380642 | 39 | fScaleQ0(0), |
40 | fScaleQ1(0), | |
5e86ff99 | 41 | fPidTracklengthCorr(kFALSE), |
5f7c3c48 | 42 | fTiltCorr(kFALSE), |
43 | fPidGainCorr(kFALSE) | |
5e86ff99 | 44 | { |
6419bebb | 45 | // default constructor |
5e86ff99 | 46 | } |
47 | ||
48 | AliTRDltuParam::~AliTRDltuParam() | |
49 | { | |
6419bebb | 50 | // destructor |
5e86ff99 | 51 | } |
52 | ||
53 | Int_t AliTRDltuParam::GetDyCorrection(Int_t det, Int_t rob, Int_t mcm) const | |
54 | { | |
55 | // calculate the correction of the deflection | |
56 | // i.e. Lorentz angle and tilt correction (if active) | |
57 | ||
58 | Int_t layer = det % 6; | |
59 | ||
16477104 | 60 | Float_t dyTilt = ( fgDriftLength * TMath::Tan(fgTiltingAngle[layer] * TMath::Pi()/180.) * |
5e86ff99 | 61 | GetLocalZ(det, rob, mcm) / fgX[layer] ); |
62 | ||
63 | // calculate Lorentz correction | |
64 | Float_t dyCorr = - fOmegaTau * fgDriftLength; | |
65 | ||
66 | if(fTiltCorr) | |
67 | dyCorr += dyTilt; // add tilt correction | |
68 | ||
69 | return (int) TMath::Nint(dyCorr * fgScalePad / fgWidthPad[layer]); | |
70 | } | |
71 | ||
72 | void AliTRDltuParam::GetDyRange(Int_t det, Int_t rob, Int_t mcm, Int_t ch, | |
73 | Int_t &dyMinInt, Int_t &dyMaxInt) const | |
74 | { | |
75 | // calculate the deflection range in which tracklets are accepted | |
76 | ||
77 | dyMinInt = fgDyMin; | |
78 | dyMaxInt = fgDyMax; | |
79 | ||
1fa993c2 | 80 | // deflection cut is considered for |B| > 0.1 T only |
39e4e4cf | 81 | if (TMath::Abs(fMagField) < 0.1) |
5e86ff99 | 82 | return; |
83 | ||
84 | Float_t e = 0.30; | |
85 | ||
1fa993c2 | 86 | Float_t maxDeflTemp = GetPerp(det, rob, mcm, ch)/2. * // Sekante/2 (cm) |
87 | (e * 1e-2 * TMath::Abs(fMagField) / fPtMin); // 1/R (1/cm) | |
5e86ff99 | 88 | |
89 | Float_t maxDeflAngle = 0.; | |
90 | ||
1fa993c2 | 91 | Float_t phi = GetPhi(det, rob, mcm, ch); |
92 | if (maxDeflTemp < TMath::Cos(phi)) { | |
5e86ff99 | 93 | maxDeflAngle = TMath::ASin(maxDeflTemp); |
94 | ||
95 | Float_t dyMin = ( fgDriftLength * | |
1fa993c2 | 96 | TMath::Tan(phi - maxDeflAngle) ); |
5e86ff99 | 97 | |
98 | dyMinInt = Int_t(dyMin / fgBinDy); | |
1fa993c2 | 99 | // clipping to allowed range |
5e86ff99 | 100 | if (dyMinInt < fgDyMin) |
101 | dyMinInt = fgDyMin; | |
1fa993c2 | 102 | else if (dyMinInt > fgDyMax) |
103 | dyMinInt = fgDyMax; | |
5e86ff99 | 104 | |
105 | Float_t dyMax = ( fgDriftLength * | |
1fa993c2 | 106 | TMath::Tan(phi + maxDeflAngle) ); |
5e86ff99 | 107 | |
108 | dyMaxInt = Int_t(dyMax / fgBinDy); | |
1fa993c2 | 109 | // clipping to allowed range |
5e86ff99 | 110 | if (dyMaxInt > fgDyMax) |
111 | dyMaxInt = fgDyMax; | |
1fa993c2 | 112 | else if (dyMaxInt < fgDyMin) |
113 | dyMaxInt = fgDyMin; | |
5e86ff99 | 114 | } |
1fa993c2 | 115 | else if (maxDeflTemp < 0.) { |
116 | // this must not happen | |
117 | printf("Inconsistent calculation of sin(alpha): %f\n", maxDeflTemp); | |
118 | } | |
119 | else { | |
120 | // TRD is not reached at the given pt threshold | |
121 | // max range | |
122 | } | |
123 | ||
5e86ff99 | 124 | if ((dyMaxInt - dyMinInt) <= 0) { |
1fa993c2 | 125 | printf("strange dy range: [%i,%i], using max range now\n", dyMinInt, dyMaxInt); |
126 | dyMaxInt = fgDyMax; | |
127 | dyMinInt = fgDyMin; | |
5e86ff99 | 128 | } |
129 | } | |
130 | ||
131 | Float_t AliTRDltuParam::GetElongation(Int_t det, Int_t rob, Int_t mcm, Int_t ch) const | |
132 | { | |
6419bebb | 133 | // calculate the ratio of the distance to the primary vertex and the |
134 | // distance in x-direction for the given ADC channel | |
135 | ||
5e86ff99 | 136 | Int_t layer = det % 6; |
137 | ||
138 | Float_t elongation = TMath::Abs(GetDist(det, rob, mcm, ch) / fgX[layer]); | |
139 | ||
140 | // sanity check | |
141 | if(elongation<0.001) { | |
142 | elongation=1.; | |
143 | } | |
144 | return elongation; | |
145 | } | |
146 | ||
147 | void AliTRDltuParam::GetCorrectionFactors(Int_t det, Int_t rob, Int_t mcm, Int_t ch, | |
5f7c3c48 | 148 | UInt_t &cor0, UInt_t &cor1, Float_t gain) const |
5e86ff99 | 149 | { |
6419bebb | 150 | // calculate the gain correction factors for the given ADC channel |
151 | ||
5f7c3c48 | 152 | if (fPidGainCorr==kFALSE) |
153 | gain=1; | |
154 | ||
5e86ff99 | 155 | if (fPidTracklengthCorr == kTRUE ) { |
5f7c3c48 | 156 | cor0 = UInt_t ((1.0*fScaleQ0* (1./GetElongation(det, rob, mcm, ch))) / gain ); |
157 | cor1 = UInt_t ((1.0*fScaleQ1* (1./GetElongation(det, rob, mcm, ch))) / gain ); | |
5e86ff99 | 158 | } |
159 | else { | |
5f7c3c48 | 160 | cor0 = UInt_t (fScaleQ0 / gain); |
161 | cor1 = UInt_t ( fScaleQ1 / gain); | |
5e86ff99 | 162 | } |
163 | } | |
164 | ||
165 | Int_t AliTRDltuParam::GetNtimebins() const | |
166 | { | |
6419bebb | 167 | // return the number of timebins used |
168 | ||
5e86ff99 | 169 | return fNtimebins; |
170 | } | |
171 | ||
172 | Float_t AliTRDltuParam::GetX(Int_t det, Int_t /* rob */, Int_t /* mcm */) const | |
173 | { | |
6419bebb | 174 | // return the distance to the beam axis in x-direction |
175 | ||
5e86ff99 | 176 | Int_t layer = det%6; |
177 | return fgX[layer]; | |
178 | } | |
179 | ||
180 | Float_t AliTRDltuParam::GetLocalY(Int_t det, Int_t rob, Int_t mcm, Int_t ch) const | |
181 | { | |
6419bebb | 182 | // get local y-position (r-phi) w.r.t. the chamber centre |
183 | ||
5e86ff99 | 184 | Int_t layer = det%6; |
185 | // calculate the pad position as in the TRAP | |
39e4e4cf | 186 | Float_t ypos = (-4 + 1 + (rob&0x1) * 4 + (mcm&0x3)) * 18 - ch - 0.5; // y position in bins of pad widths |
5e86ff99 | 187 | return ypos*fgWidthPad[layer]; |
188 | } | |
189 | ||
190 | Float_t AliTRDltuParam::GetLocalZ(Int_t det, Int_t rob, Int_t mcm) const | |
191 | { | |
6419bebb | 192 | // get local z-position w.r.t. to the chamber boundary |
193 | ||
5e86ff99 | 194 | Int_t stack = (det%30) / 6; |
195 | Int_t layer = det % 6; | |
196 | Int_t row = (rob/2) * 4 + mcm/4; | |
197 | ||
198 | if (stack == 2) { | |
199 | if (row == 0) | |
200 | return (fgZrow[layer][stack] - 0.5 * fgLengthOuterPadC0); | |
201 | else if (row == 11) | |
202 | return (fgZrow[layer][stack] - 1.5 * fgLengthOuterPadC0 - (row - 1) * fgLengthInnerPadC0); | |
203 | else | |
204 | return (fgZrow[layer][stack] - fgLengthOuterPadC0 - (row - 0.5) * fgLengthInnerPadC0); | |
205 | } | |
206 | else { | |
207 | if (row == 0) | |
208 | return (fgZrow[layer][stack] - 0.5 * fgLengthOuterPadC1[layer]); | |
209 | else if (row == 15) | |
210 | return (fgZrow[layer][stack] - 1.5 * fgLengthOuterPadC1[layer] - (row - 1) * fgLengthInnerPadC1[layer]); | |
211 | else | |
212 | return (fgZrow[layer][stack] - fgLengthOuterPadC1[layer] - (row - 0.5) * fgLengthInnerPadC1[layer]); | |
213 | } | |
214 | } | |
215 | ||
216 | Float_t AliTRDltuParam::GetPerp(Int_t det, Int_t rob, Int_t mcm, Int_t ch) const | |
217 | { | |
6419bebb | 218 | // get transverse distance to the beam axis |
219 | ||
5e86ff99 | 220 | return TMath::Sqrt(GetLocalY(det, rob, mcm, ch)*GetLocalY(det, rob, mcm, ch) + |
221 | GetX(det, rob, mcm)*GetX(det, rob, mcm) ); | |
222 | } | |
223 | ||
224 | Float_t AliTRDltuParam::GetPhi(Int_t det, Int_t rob, Int_t mcm, Int_t ch) const | |
225 | { | |
6419bebb | 226 | // calculate the azimuthal angle for the given ADC channel |
227 | ||
5e86ff99 | 228 | return TMath::ATan2(GetLocalY(det, rob, mcm, ch), GetX(det, rob, mcm)); |
229 | } | |
230 | ||
231 | Float_t AliTRDltuParam::GetDist(Int_t det, Int_t rob, Int_t mcm, Int_t ch) const | |
232 | { | |
6419bebb | 233 | // calculate the distance from the origin for the given ADC channel |
234 | ||
5e86ff99 | 235 | return TMath::Sqrt(GetLocalY(det, rob, mcm, ch)*GetLocalY(det, rob, mcm, ch) + |
236 | GetX(det, rob, mcm)*GetX(det, rob, mcm) + | |
237 | GetLocalZ(det, rob, mcm)*GetLocalZ(det, rob, mcm) ); | |
238 | } |