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cd2a0045 | 1 | /************************************************************************** |
2 | * Copyright(c) 2007-2009, 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 | ||
2ae37d58 | 16 | /* $Id$ */ |
cd2a0045 | 17 | |
18 | /////////////////////////////////////////////////////////////////// | |
19 | // // | |
20 | // Implementation of the class to store the parameters used in // | |
21 | // the simulation of SPD, SDD and SSD detectors // | |
22 | // Origin: F.Prino, Torino, prino@to.infn.it // | |
23 | // // | |
24 | /////////////////////////////////////////////////////////////////// | |
25 | ||
26 | #include "AliITSSimuParam.h" | |
27 | #include <TMath.h> | |
28 | ||
29 | const Float_t AliITSSimuParam::fgkSPDBiasVoltageDefault = 18.182; | |
30 | const Double_t AliITSSimuParam::fgkSPDThreshDefault = 3000.; | |
31 | const Double_t AliITSSimuParam::fgkSPDSigmaDefault = 250.; | |
32 | const TString AliITSSimuParam::fgkSPDCouplingOptDefault = "old"; | |
33 | const Double_t AliITSSimuParam::fgkSPDCouplColDefault = 0.; | |
34 | const Double_t AliITSSimuParam::fgkSPDCouplRowDefault = 0.055; | |
35 | const Float_t AliITSSimuParam::fgkSPDEccDiffDefault = 0.85; | |
36 | const Float_t AliITSSimuParam::fgkSDDDiffCoeffDefault = 3.23; | |
37 | const Float_t AliITSSimuParam::fgkSDDDiffCoeff1Default = 30.; | |
38 | const Float_t AliITSSimuParam::fgkSDDJitterErrorDefault = 20.; // 20 um from beam test 2001 | |
39 | const Float_t AliITSSimuParam::fgkSDDDynamicRangeDefault = 132.; | |
40 | const Int_t AliITSSimuParam::fgkSDDMaxAdcDefault = 1024; | |
41 | const Float_t AliITSSimuParam::fgkSDDChargeLossDefault = 0.; | |
42 | const Double_t AliITSSimuParam::fgkSSDCouplingPRDefault = 0.01; | |
43 | const Double_t AliITSSimuParam::fgkSSDCouplingPLDefault = 0.01; | |
44 | const Double_t AliITSSimuParam::fgkSSDCouplingNRDefault = 0.01; | |
45 | const Double_t AliITSSimuParam::fgkSSDCouplingNLDefault = 0.01; | |
46 | const Int_t AliITSSimuParam::fgkSSDZSThresholdDefault = 3; | |
47 | ||
48 | const Float_t AliITSSimuParam::fgkNsigmasDefault = 3.; | |
49 | const Int_t AliITSSimuParam::fgkNcompsDefault = 121; | |
50 | ||
51 | ClassImp(AliITSSimuParam) | |
52 | ||
53 | //______________________________________________________________________ | |
54 | AliITSSimuParam::AliITSSimuParam(): | |
55 | TObject(), | |
56 | fGeVcharge(0.), | |
57 | fDOverV(0.), | |
2ae37d58 | 58 | //fSPDBiasVoltage(fgkSPDBiasVoltageDefault), |
59 | //fSPDThresh(fgkSPDThreshDefault), | |
60 | //fSPDSigma(fgkSPDSigmaDefault), | |
cd2a0045 | 61 | fSPDCouplOpt(0), |
62 | fSPDCouplCol(fgkSPDCouplColDefault), | |
63 | fSPDCouplRow(fgkSPDCouplRowDefault), | |
64 | fSPDEccDiff(0.), | |
65 | fSDDElectronics(0), | |
66 | fSDDDiffCoeff(0.), | |
67 | fSDDDiffCoeff1(0.), | |
68 | fSDDJitterError(fgkSDDJitterErrorDefault), | |
69 | fSDDDynamicRange(fgkSDDDynamicRangeDefault), | |
70 | fSDDMaxAdc(0.), | |
71 | fSDDChargeLoss(fgkSDDChargeLossDefault), | |
72 | fSSDADCpereV(0.), | |
73 | fSSDCouplingPR(0), | |
74 | fSSDCouplingPL(0), | |
75 | fSSDCouplingNR(0), | |
76 | fSSDCouplingNL(0), | |
77 | fSSDZSThreshold(fgkSSDZSThresholdDefault), | |
78 | fNsigmas(fgkNsigmasDefault), | |
79 | fNcomps(fgkNcompsDefault), | |
2ae37d58 | 80 | fGaus(), |
81 | fN(0.), | |
82 | fT(300.) | |
cd2a0045 | 83 | { |
84 | // default constructor | |
2ae37d58 | 85 | SetSPDBiasVoltageAll(fgkSPDBiasVoltageDefault); |
86 | SetSPDThresholdsAll(fgkSPDThreshDefault,fgkSPDSigmaDefault); | |
87 | SetSPDNoiseAll(0,0); | |
cd2a0045 | 88 | SetGeVToCharge(); |
89 | SetDistanceOverVoltage(); | |
90 | SetSPDCouplingOption(fgkSPDCouplingOptDefault); | |
91 | SetSPDSigmaDiffusionAsymmetry(fgkSPDEccDiffDefault); | |
92 | SetSDDElectronics(); | |
93 | SetSDDDiffCoeff(fgkSDDDiffCoeffDefault,fgkSDDDiffCoeff1Default); | |
94 | SetSDDMaxAdc((Double_t)fgkSDDMaxAdcDefault); | |
95 | SetSSDADCpereV(); | |
96 | SetSSDCouplings(fgkSSDCouplingPRDefault,fgkSSDCouplingPLDefault,fgkSSDCouplingNRDefault,fgkSSDCouplingNLDefault); | |
97 | } | |
98 | //______________________________________________________________________ | |
99 | AliITSSimuParam::AliITSSimuParam(const AliITSSimuParam &simpar): | |
100 | TObject(), | |
101 | fGeVcharge(simpar.fGeVcharge), | |
102 | fDOverV(simpar.fDOverV), | |
2ae37d58 | 103 | //fSPDBiasVoltage(simpar.fSPDBiasVoltage), |
104 | //fSPDThresh(simpar.fSPDThresh), | |
105 | //fSPDSigma(simpar.fSPDSigma), | |
cd2a0045 | 106 | fSPDCouplOpt(simpar.fSPDCouplOpt), |
107 | fSPDCouplCol(simpar.fSPDCouplCol), | |
108 | fSPDCouplRow(simpar.fSPDCouplRow), | |
109 | fSPDEccDiff(simpar.fSPDEccDiff), | |
110 | fSDDElectronics(simpar.fSDDElectronics), | |
111 | fSDDDiffCoeff(simpar.fSDDDiffCoeff), | |
112 | fSDDDiffCoeff1(simpar.fSDDDiffCoeff1), | |
113 | fSDDJitterError(simpar.fSDDJitterError), | |
114 | fSDDDynamicRange(simpar.fSDDDynamicRange), | |
115 | fSDDMaxAdc(simpar.fSDDMaxAdc), | |
116 | fSDDChargeLoss(simpar.fSDDChargeLoss), | |
117 | fSSDADCpereV(simpar.fSSDADCpereV), | |
118 | fSSDCouplingPR(simpar.fSSDCouplingPR), | |
119 | fSSDCouplingPL(simpar.fSSDCouplingPL), | |
120 | fSSDCouplingNR(simpar.fSSDCouplingNR), | |
121 | fSSDCouplingNL(simpar.fSSDCouplingNL), | |
122 | fSSDZSThreshold(simpar.fSSDZSThreshold), | |
123 | fNsigmas(simpar.fNsigmas), | |
124 | fNcomps(simpar.fNcomps), | |
2ae37d58 | 125 | fGaus(), |
126 | fN(simpar.fN), | |
127 | fT(simpar.fT){ | |
cd2a0045 | 128 | // copy constructor |
2ae37d58 | 129 | for (Int_t i=0;i<240;i++) { |
130 | fSPDBiasVoltage[i]=simpar.fSPDBiasVoltage[i]; | |
131 | fSPDThresh[i]=simpar.fSPDThresh[i]; | |
132 | fSPDSigma[i]=simpar.fSPDSigma[i]; | |
133 | fSPDNoise[i]=simpar.fSPDNoise[i]; | |
134 | fSPDBaseline[i]=simpar.fSPDBaseline[i]; | |
135 | } | |
cd2a0045 | 136 | } |
137 | ||
138 | //______________________________________________________________________ | |
139 | AliITSSimuParam& AliITSSimuParam::operator=(const AliITSSimuParam& source){ | |
140 | // Assignment operator. | |
141 | this->~AliITSSimuParam(); | |
142 | new(this) AliITSSimuParam(source); | |
143 | return *this; | |
144 | ||
145 | } | |
146 | ||
147 | ||
148 | //______________________________________________________________________ | |
149 | AliITSSimuParam::~AliITSSimuParam() { | |
150 | // destructor | |
151 | if(fGaus) delete fGaus; | |
152 | } | |
153 | //________________________________________________________________________ | |
154 | void AliITSSimuParam::SetNLookUp(Int_t p1){ | |
155 | // Set number of sigmas over which cluster disintegration is performed | |
156 | fNcomps=p1; | |
157 | if (fGaus) delete fGaus; | |
158 | fGaus = new TArrayF(fNcomps+1); | |
159 | for(Int_t i=0; i<=fNcomps; i++) { | |
160 | Float_t x = -fNsigmas + (2.*i*fNsigmas)/(fNcomps-1); | |
161 | (*fGaus)[i] = exp(-((x*x)/2)); | |
162 | } | |
163 | } | |
164 | //________________________________________________________________________ | |
165 | void AliITSSimuParam::PrintParameters() const{ | |
166 | printf("GeVToCharge = %G\n",fGeVcharge); | |
167 | printf("DistanveOverVoltage = %f \n",fDOverV); | |
168 | printf("\n"); | |
169 | printf("===== SPD parameters =====\n"); | |
2ae37d58 | 170 | printf("Bias Voltage = %f \n",fSPDBiasVoltage[0]); |
171 | printf("Threshold and sigma = %f %f\n",fSPDThresh[0],fSPDSigma[0]); | |
cd2a0045 | 172 | printf("Coupling Option = %s\n",fSPDCouplOpt.Data()); |
173 | printf("Coupling value (column) = %f\n",fSPDCouplCol); | |
174 | printf("Coupling value (row) = %f\n",fSPDCouplRow); | |
175 | printf("Eccentricity in diffusion = %f\n",fSPDEccDiff); | |
176 | printf("\n"); | |
177 | printf("===== SDD parameters =====\n"); | |
178 | printf("Electronic chips = %d\n",fSDDElectronics); | |
179 | printf("Diffusion Coefficients = %f %f\n",fSDDDiffCoeff,fSDDDiffCoeff1); | |
180 | printf("Jitter Error = %f um\n",fSDDJitterError); | |
181 | printf("Dynamic Range = %f\n",fSDDDynamicRange); | |
182 | printf("Max. ADC = %f\n",fSDDMaxAdc); | |
183 | printf("Charge Loss = %f\n",fSDDChargeLoss); | |
184 | printf("\n"); | |
185 | printf("===== SSD parameters =====\n"); | |
186 | printf("ADC per eV = %f\n",fSSDADCpereV); | |
187 | printf("Coupling PR = %f\n",fSSDCouplingPR); | |
188 | printf("Coupling PL = %f\n",fSSDCouplingPL); | |
189 | printf("Coupling NR = %f\n",fSSDCouplingNR); | |
190 | printf("Coupling NL = %f\n",fSSDCouplingNL); | |
191 | printf("Zero Supp threshold = %d\n",fSSDZSThreshold); | |
192 | } | |
2ae37d58 | 193 | //______________________________________________________________________ |
194 | Double_t AliITSSimuParam::MobilityElectronSiEmp() const { | |
195 | // Computes the electron mobility in cm^2/volt-sec. Taken from SILVACO | |
196 | // International ATLAS II, 2D Device Simulation Framework, User Manual | |
197 | // Chapter 5 Equation 5-6. An empirical function for low-field mobiliity | |
198 | // in silicon at different tempeatures. | |
199 | // Inputs: | |
200 | // none. | |
201 | // Output: | |
202 | // none. | |
203 | // Return: | |
204 | // The Mobility of electrons in Si at a give temprature and impurity | |
205 | // concentration. [cm^2/Volt-sec] | |
206 | const Double_t km0 = 55.24; // cm^2/Volt-sec | |
207 | const Double_t km1 = 7.12E+08; // cm^2 (degree K)^2.3 / Volt-sec | |
208 | const Double_t kN0 = 1.072E17; // #/cm^3 | |
209 | const Double_t kT0 = 300.; // degree K. | |
210 | const Double_t keT0 = -2.3; // Power of Temp. | |
211 | const Double_t keT1 = -3.8; // Power of Temp. | |
212 | const Double_t keN = 0.73; // Power of Dopent Consentrations | |
213 | Double_t m; | |
214 | Double_t tT = fT,nN = fN; | |
215 | ||
216 | if(nN<=0.0){ // Simple case. | |
217 | if(tT==300.) return 1350.0; // From Table 5-1 at consentration 1.0E14. | |
218 | m = km1*TMath::Power(tT,keT0); | |
219 | return m; | |
220 | } // if nN<=0.0 | |
221 | m = km1*TMath::Power(tT,keT0) - km0; | |
222 | m /= 1.0 + TMath::Power(tT/kT0,keT1)*TMath::Power(nN/kN0,keN); | |
223 | m += km0; | |
224 | return m; | |
225 | } | |
226 | //______________________________________________________________________ | |
227 | Double_t AliITSSimuParam::MobilityHoleSiEmp() const { | |
228 | // Computes the Hole mobility in cm^2/volt-sec. Taken from SILVACO | |
229 | // International ATLAS II, 2D Device Simulation Framework, User Manual | |
230 | // Chapter 5 Equation 5-7 An empirical function for low-field mobiliity | |
231 | // in silicon at different tempeatures. | |
232 | // Inputs: | |
233 | // none. | |
234 | // Output: | |
235 | // none. | |
236 | // Return: | |
237 | // The Mobility of Hole in Si at a give temprature and impurity | |
238 | // concentration. [cm^2/Volt-sec] | |
239 | const Double_t km0a = 49.74; // cm^2/Volt-sec | |
240 | const Double_t km0b = 49.70; // cm^2/Volt-sec | |
241 | const Double_t km1 = 1.35E+08; // cm^2 (degree K)^2.3 / Volt-sec | |
242 | const Double_t kN0 = 1.606E17; // #/cm^3 | |
243 | const Double_t kT0 = 300.; // degree K. | |
244 | const Double_t keT0 = -2.2; // Power of Temp. | |
245 | const Double_t keT1 = -3.7; // Power of Temp. | |
246 | const Double_t keN = 0.70; // Power of Dopent Consentrations | |
247 | Double_t m; | |
248 | Double_t tT = fT,nN = fN; | |
249 | ||
250 | if(nN<=0.0){ // Simple case. | |
251 | if(tT==300.) return 495.0; // From Table 5-1 at consentration 1.0E14. | |
252 | m = km1*TMath::Power(tT,keT0) + km0a-km0b; | |
253 | return m; | |
254 | } // if nN<=0.0 | |
255 | m = km1*TMath::Power(tT,keT0) - km0b; | |
256 | m /= 1.0 + TMath::Power(tT/kT0,keT1)*TMath::Power(nN/kN0,keN); | |
257 | m += km0a; | |
258 | return m; | |
259 | } | |
260 | //______________________________________________________________________ | |
261 | Double_t AliITSSimuParam::DiffusionCoefficientElectron() const { | |
262 | // Computes the Diffusion coefficient for electrons in cm^2/sec. Taken | |
263 | // from SILVACO International ATLAS II, 2D Device Simulation Framework, | |
264 | // User Manual Chapter 5 Equation 5-53. Einstein relations for diffusion | |
265 | // coefficient. Note: 1 cm^2/sec = 10 microns^2/nanosec. | |
266 | // Inputs: | |
267 | // none. | |
268 | // Output: | |
269 | // none. | |
270 | // Return: | |
271 | // The Diffusion Coefficient of electrons in Si at a give temprature | |
272 | // and impurity concentration. [cm^2/sec] | |
273 | // const Double_t kb = 1.3806503E-23; // Joules/degree K | |
274 | // const Double_t qe = 1.60217646E-19; // Coulumbs. | |
275 | const Double_t kbqe = 8.617342312E-5; // Volt/degree K | |
276 | Double_t m = MobilityElectronSiEmp(); | |
277 | Double_t tT = fT; | |
278 | ||
279 | return m*kbqe*tT; // [cm^2/sec] | |
280 | } | |
281 | //______________________________________________________________________ | |
282 | Double_t AliITSSimuParam::DiffusionCoefficientHole() const { | |
283 | // Computes the Diffusion coefficient for Holes in cm^2/sec. Taken | |
284 | // from SILVACO International ATLAS II, 2D Device Simulation Framework, | |
285 | // User Manual Chapter 5 Equation 5-53. Einstein relations for diffusion | |
286 | // coefficient. Note: 1 cm^2/sec = 10 microns^2/nanosec. | |
287 | // Inputs: | |
288 | // none. | |
289 | // Output: | |
290 | // none. | |
291 | // Return: | |
292 | // The Defusion Coefficient of Hole in Si at a give temprature and | |
293 | // impurity concentration. [cm^2/sec] | |
294 | // and impurity concentration. [cm^2/sec] | |
295 | // const Double_t kb = 1.3806503E-23; // Joules/degree K | |
296 | // const Double_t qe = 1.60217646E-19; // Coulumbs. | |
297 | const Double_t kbqe = 8.617342312E-5; // Volt/degree K | |
298 | Double_t m = MobilityHoleSiEmp(); | |
299 | Double_t tT = fT; | |
300 | ||
301 | return m*kbqe*tT; // [cm^2/sec] | |
302 | } | |
303 | //______________________________________________________________________ | |
304 | Double_t AliITSSimuParam::LorentzAngleHole(Double_t B) const { | |
305 | // Computes the Lorentz angle for electrons in Si | |
306 | // Input: magnetic Field in KGauss | |
307 | // Output: Lorentz angle in radians (positive if Bz is positive) | |
308 | // Main Reference: NIM A 497 (2003) 389–396. | |
309 | // "An algorithm for calculating the Lorentz angle in silicon detectors", V. Bartsch et al. | |
310 | // | |
311 | const Double_t krH=0.70; // Hall scattering factor for Hole | |
312 | const Double_t kT0 = 300.; // reference Temperature (degree K). | |
313 | const Double_t kmulow0 = 470.5; // cm^2/Volt-sec | |
314 | const Double_t keT0 = -2.5; // Power of Temp. | |
315 | const Double_t beta0 = 1.213; // beta coeff. at T0=300K | |
316 | const Double_t keT1 = 0.17; // Power of Temp. for beta | |
317 | const Double_t kvsat0 = 8.37E+06; // saturated velocity at T0=300K (cm/sec) | |
318 | const Double_t keT2 = 0.52; // Power of Temp. for vsat | |
319 | Double_t tT = fT; | |
320 | Double_t eE= 1./fDOverV; | |
321 | Double_t muLow=kmulow0*TMath::Power(tT/kT0,keT0); | |
322 | Double_t beta=beta0*TMath::Power(tT/kT0,keT1); | |
323 | Double_t vsat=kvsat0*TMath::Power(tT/kT0,keT2); | |
324 | Double_t mu=muLow/TMath::Power(1+TMath::Power(muLow*eE/vsat,beta),1/beta); | |
325 | Double_t angle=TMath::ATan(krH*mu*B*1.E-05); // Conversion Factor | |
326 | return angle; | |
327 | } | |
328 | //______________________________________________________________________ | |
329 | Double_t AliITSSimuParam::LorentzAngleElectron(Double_t B) const { | |
330 | // Computes the Lorentz angle for electrons in Si | |
331 | // Input: magnetic Field in KGauss | |
332 | // Output: Lorentz angle in radians (positive if Bz is positive) | |
333 | // Main Reference: NIM A 497 (2003) 389–396. | |
334 | // "An algorithm for calculating the Lorentz angle in silicon detectors", V. Bartsch et al. | |
335 | // | |
336 | const Double_t krH=1.15; // Hall scattering factor for Electron | |
337 | const Double_t kT0 = 300.; // reference Temperature (degree K). | |
338 | const Double_t kmulow0 = 1417.0; // cm^2/Volt-sec | |
339 | const Double_t keT0 = -2.2; // Power of Temp. | |
340 | const Double_t beta0 = 1.109; // beta coeff. at T0=300K | |
341 | const Double_t keT1 = 0.66; // Power of Temp. for beta | |
342 | const Double_t kvsat0 = 1.07E+07; // saturated velocity at T0=300K (cm/sec) | |
343 | const Double_t keT2 = 0.87; // Power of Temp. for vsat | |
344 | Double_t tT = fT; | |
345 | Double_t eE= 1./fDOverV; | |
346 | Double_t muLow=kmulow0*TMath::Power(tT/kT0,keT0); | |
347 | Double_t beta=beta0*TMath::Power(tT/kT0,keT1); | |
348 | Double_t vsat=kvsat0*TMath::Power(tT/kT0,keT2); | |
349 | Double_t mu=muLow/TMath::Power(1+TMath::Power(muLow*eE/vsat,beta),1/beta); | |
350 | Double_t angle=TMath::ATan(krH*mu*B*1.E-05); | |
351 | return angle; | |
352 | } | |
353 | //______________________________________________________________________ | |
354 | Double_t AliITSSimuParam::SpeedElectron() const { | |
355 | // Computes the average speed for electrons in Si under the low-field | |
356 | // approximation. [cm/sec]. | |
357 | // Inputs: | |
358 | // none. | |
359 | // Output: | |
360 | // none. | |
361 | // Return: | |
362 | // The speed the holes are traveling at due to the low field applied. | |
363 | // [cm/sec] | |
364 | Double_t m = MobilityElectronSiEmp(); | |
365 | ||
366 | return m/fDOverV; // [cm/sec] | |
367 | } | |
368 | //______________________________________________________________________ | |
369 | Double_t AliITSSimuParam::SpeedHole() const { | |
370 | // Computes the average speed for Holes in Si under the low-field | |
371 | // approximation.[cm/sec]. | |
372 | // Inputs: | |
373 | // none. | |
374 | // Output: | |
375 | // none. | |
376 | // Return: | |
377 | // The speed the holes are traveling at due to the low field applied. | |
378 | // [cm/sec] | |
379 | Double_t m = MobilityHoleSiEmp(); | |
380 | ||
381 | return m/fDOverV; // [cm/sec] | |
382 | } | |
383 | //______________________________________________________________________ | |
384 | Double_t AliITSSimuParam::SigmaDiffusion3D(Double_t l) const { | |
385 | // Returns the Gaussian sigma^2 == <x^2+y^2+z^2> [cm^2] due to the | |
386 | // defusion of electrons or holes through a distance l [cm] caused | |
387 | // by an applied voltage v [volt] through a distance d [cm] in any | |
388 | // material at a temperature T [degree K]. The sigma diffusion when | |
389 | // expressed in terms of the distance over which the diffusion | |
390 | // occures, l=time/speed, is independent of the mobility and therefore | |
391 | // the properties of the material. The charge distributions is given by | |
392 | // n = exp(-r^2/4Dt)/(4piDt)^1.5. From this <r^2> = 6Dt where D=mkT/e | |
393 | // (m==mobility, k==Boltzman's constant, T==temparature, e==electric | |
394 | // charge. and vel=m*v/d. consiquently sigma^2=6kTdl/ev. | |
395 | // Inputs: | |
396 | // Double_t l Distance the charge has to travel. | |
397 | // Output: | |
398 | // none. | |
399 | // Return: | |
400 | // The Sigma due to the diffution of electrons. [cm] | |
401 | const Double_t kcon = 5.17040258E-04; // == 6k/e [J/col or volts] | |
402 | ||
403 | return TMath::Sqrt(kcon*fT*fDOverV*l); // [cm] | |
404 | } | |
405 | //______________________________________________________________________ | |
406 | Double_t AliITSSimuParam::SigmaDiffusion2D(Double_t l) const { | |
407 | // Returns the Gaussian sigma^2 == <x^2+z^2> [cm^2] due to the defusion | |
408 | // of electrons or holes through a distance l [cm] caused by an applied | |
409 | // voltage v [volt] through a distance d [cm] in any material at a | |
410 | // temperature T [degree K]. The sigma diffusion when expressed in terms | |
411 | // of the distance over which the diffusion occures, l=time/speed, is | |
412 | // independent of the mobility and therefore the properties of the | |
413 | // material. The charge distributions is given by | |
414 | // n = exp(-r^2/4Dt)/(4piDt)^1.5. From this <x^2+z^2> = 4Dt where D=mkT/e | |
415 | // (m==mobility, k==Boltzman's constant, T==temparature, e==electric | |
416 | // charge. and vel=m*v/d. consiquently sigma^2=4kTdl/ev. | |
417 | // Inputs: | |
418 | // Double_t l Distance the charge has to travel. | |
419 | // Output: | |
420 | // none. | |
421 | // Return: | |
422 | // The Sigma due to the diffution of electrons. [cm] | |
423 | const Double_t kcon = 3.446935053E-04; // == 4k/e [J/col or volts] | |
424 | ||
425 | return TMath::Sqrt(kcon*fT*fDOverV*l); // [cm] | |
426 | } | |
427 | //______________________________________________________________________ | |
428 | Double_t AliITSSimuParam::SigmaDiffusion1D(Double_t l) const { | |
429 | // Returns the Gaussian sigma^2 == <x^2> [cm^2] due to the defusion | |
430 | // of electrons or holes through a distance l [cm] caused by an applied | |
431 | // voltage v [volt] through a distance d [cm] in any material at a | |
432 | // temperature T [degree K]. The sigma diffusion when expressed in terms | |
433 | // of the distance over which the diffusion occures, l=time/speed, is | |
434 | // independent of the mobility and therefore the properties of the | |
435 | // material. The charge distributions is given by | |
436 | // n = exp(-r^2/4Dt)/(4piDt)^1.5. From this <r^2> = 2Dt where D=mkT/e | |
437 | // (m==mobility, k==Boltzman's constant, T==temparature, e==electric | |
438 | // charge. and vel=m*v/d. consiquently sigma^2=2kTdl/ev. | |
439 | // Inputs: | |
440 | // Double_t l Distance the charge has to travel. | |
441 | // Output: | |
442 | // none. | |
443 | // Return: | |
444 | // The Sigma due to the diffution of electrons. [cm] | |
445 | const Double_t kcon = 1.723467527E-04; // == 2k/e [J/col or volts] | |
446 | ||
447 | return TMath::Sqrt(kcon*fT*fDOverV*l); // [cm] | |
448 | } | |
449 | //---------------------------------------------------------------------- | |
450 | Double_t AliITSSimuParam::DepletedRegionThicknessA(Double_t dopCons, | |
451 | Double_t voltage, | |
452 | Double_t elecCharge, | |
453 | Double_t voltBuiltIn)const{ | |
454 | // Computes the thickness of the depleted region in Si due to the | |
455 | // application of an external bias voltage. From the Particle Data | |
456 | // Book, 28.8 Silicon semiconductor detectors equation 28.19 (2004) | |
457 | // Physics Letters B "Review of Particle Physics" Volume 592, Issue 1-4 | |
458 | // July 15 2004, ISSN 0370-2693 page 263. First equation. | |
459 | // Inputs: | |
460 | // Double_t dopCons "N" doping concentration | |
461 | // Double_t voltage "V" external bias voltage | |
462 | // Double_t elecCharge "e" electronic charge | |
463 | // Double_t voltBuiltIn=0.5 "V_bi" "built-in" Voltage (~0.5V for | |
464 | // resistivities typically used in detectors) | |
465 | // Output: | |
466 | // none. | |
467 | // Return: | |
468 | // The thickness of the depleted region | |
469 | ||
470 | return TMath::Sqrt(2.0*(voltage+voltBuiltIn)/(dopCons*elecCharge)); | |
471 | } | |
472 | //---------------------------------------------------------------------- | |
473 | Double_t AliITSSimuParam::DepletedRegionThicknessB(Double_t resist, | |
474 | Double_t voltage, | |
475 | Double_t mobility, | |
476 | Double_t voltBuiltIn, | |
477 | Double_t dielConst)const{ | |
478 | // Computes the thickness of the depleted region in Si due to the | |
479 | // application of an external bias voltage. From the Particle Data | |
480 | // Book, 28.8 Silicon semiconductor detectors equation 28.19 (2004) | |
481 | // Physics Letters B "Review of Particle Physics" Volume 592, Issue 1-4 | |
482 | // July 15 2004, ISSN 0370-2693 page 263. Second Equation. | |
483 | // Inputs: | |
484 | // Double_t resist "rho" resistivity (typically 1-10 kOhm cm) | |
485 | // Double_t voltage "V" external bias voltage | |
486 | // Double_t mobility "mu" charge carrier mobility | |
487 | // (electons 1350, holes 450 cm^2/V/s) | |
488 | // Double_t voltBuiltIn=0.5 "V_bi" "built-in" Voltage (~0.5V for | |
489 | // resistivities typically used in detectors) | |
490 | // Double_t dielConst=1.E-12 "epsilon" dielectric constant = 11.9 * | |
491 | // (permittivity of free space) or ~ 1 pF/cm | |
492 | // Output: | |
493 | // none. | |
494 | // Return: | |
495 | // The thickness of the depleted region | |
496 | ||
497 | return TMath::Sqrt(2.8*resist*mobility*dielConst*(voltage+voltBuiltIn)); | |
498 | } | |
499 | //---------------------------------------------------------------------- | |
500 | Double_t AliITSSimuParam::ReverseBiasCurrent(Double_t temp, | |
501 | Double_t revBiasCurT1, | |
502 | Double_t tempT1, | |
503 | Double_t energy)const{ | |
504 | // Computes the temperature dependance of the reverse bias current | |
505 | // of Si detectors. From the Particle Data | |
506 | // Book, 28.8 Silicon semiconductor detectors equation 28.21 (2004) | |
507 | // Physics Letters B "Review of Particle Physics" Volume 592, Issue 1-4 | |
508 | // July 15 2004, ISSN 0370-2693 page 263. | |
509 | // Inputs: | |
510 | // Double_t temp The temperature at which the current is wanted | |
511 | // Double_t revBiasCurT1 The reference bias current at temp T1 | |
512 | // Double_t tempT1 The temperature correstponding to revBiasCurT1 | |
513 | // Double_t energy=1.2 Some energy [eV] | |
514 | // Output: | |
515 | // none. | |
516 | // Return: | |
517 | // The reverse bias current at the tempeature temp. | |
518 | const Double_t kBoltz = 8.617343E-5; //[eV/K] | |
519 | ||
520 | return revBiasCurT1*(temp*temp/(tempT1*tempT1))* | |
521 | TMath::Exp(-0.5*energy*(tempT1-temp)/(kBoltz*tempT1*temp)); | |
522 | } | |
523 | //______________________________________________________________________ | |
524 | void AliITSSimuParam::SPDThresholds(const Int_t mod, Double_t& thresh, Double_t& sigma) const { | |
525 | if(mod<0 || mod>239) { | |
526 | thresh=0; | |
527 | sigma=0; | |
528 | return; | |
529 | } | |
530 | thresh=fSPDThresh[mod]; | |
531 | sigma=fSPDSigma[mod]; | |
532 | return; | |
533 | } | |
534 | //_______________________________________________________________________ | |
535 | void AliITSSimuParam::SPDNoise(const Int_t mod,Double_t &noise, Double_t &baseline) const { | |
536 | if(mod<0 || mod>239) { | |
537 | noise=0; | |
538 | baseline=0; | |
539 | return; | |
540 | } | |
541 | noise=fSPDNoise[mod]; | |
542 | baseline=fSPDBaseline[mod]; | |
543 | return; | |
544 | } | |
545 |