Line data Source code
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 :
16 : /* $Id$ */
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.;
32 116 : 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::fgkSPDLorentzHoleWeightDefault = 1.0;
37 : const Float_t AliITSSimuParam::fgkSDDDiffCoeffDefault = 3.23;
38 : const Float_t AliITSSimuParam::fgkSDDDiffCoeff1Default = 30.;
39 : const Float_t AliITSSimuParam::fgkSDDJitterErrorDefault = 20.; // 20 um from beam test 2001
40 : const Float_t AliITSSimuParam::fgkSDDDynamicRangeDefault = 1400./2.5; // mV/MOhm = nA
41 : const Int_t AliITSSimuParam::fgkSDDMaxAdcDefault = 1024;
42 : const Float_t AliITSSimuParam::fgkSDDChargeLossDefault = 0.;
43 : const Float_t AliITSSimuParam::fgkSDDTrigDelayDefault = 54.3;
44 : const Float_t AliITSSimuParam::fgkSDDMapPrecDefault = 20.; // 20 um from laser tests
45 : const Float_t AliITSSimuParam::fgkSDDkeVtoADCDefault = 3.42;
46 : const Double_t AliITSSimuParam::fgkSSDCouplingPRDefault = 0.01;
47 : const Double_t AliITSSimuParam::fgkSSDCouplingPLDefault = 0.01;
48 : const Double_t AliITSSimuParam::fgkSSDCouplingNRDefault = 0.01;
49 : const Double_t AliITSSimuParam::fgkSSDCouplingNLDefault = 0.01;
50 : const Int_t AliITSSimuParam::fgkSSDZSThresholdDefault = 3;
51 :
52 : const Float_t AliITSSimuParam::fgkNsigmasDefault = 3.;
53 : const Int_t AliITSSimuParam::fgkNcompsDefault = 121;
54 :
55 116 : ClassImp(AliITSSimuParam)
56 :
57 : //______________________________________________________________________
58 : AliITSSimuParam::AliITSSimuParam():
59 14 : TObject(),
60 14 : fGeVcharge(0.),
61 14 : fDOverV(0.),
62 : //fSPDBiasVoltage(fgkSPDBiasVoltageDefault),
63 : //fSPDThresh(fgkSPDThreshDefault),
64 : //fSPDSigma(fgkSPDSigmaDefault),
65 14 : fSPDCouplOpt(0),
66 14 : fSPDCouplCol(fgkSPDCouplColDefault),
67 14 : fSPDCouplRow(fgkSPDCouplRowDefault),
68 14 : fSPDEccDiff(0.),
69 14 : fSPDLorentzDrift(kTRUE),
70 14 : fSPDLorentzHoleWeight(fgkSPDLorentzHoleWeightDefault),
71 14 : fSPDAddNoisyFlag(kFALSE),
72 14 : fSPDRemoveDeadFlag(kFALSE),
73 14 : fSDDElectronics(0),
74 14 : fSDDDiffCoeff(0.),
75 14 : fSDDDiffCoeff1(0.),
76 14 : fSDDJitterError(fgkSDDJitterErrorDefault),
77 14 : fSDDDynamicRange(fgkSDDDynamicRangeDefault),
78 14 : fSDDMaxAdc(0.),
79 14 : fSDDChargeLoss(fgkSDDChargeLossDefault),
80 14 : fSDDTrigDelay(fgkSDDTrigDelayDefault),
81 14 : fSDDMapPrec(fgkSDDMapPrecDefault),
82 14 : fSDDkeVtoADC(fgkSDDkeVtoADCDefault),
83 14 : fSDDRawFormat(7),
84 14 : fSSDLorentzDrift(kTRUE),
85 14 : fSSDCouplingPR(0),
86 14 : fSSDCouplingPL(0),
87 14 : fSSDCouplingNR(0),
88 14 : fSSDCouplingNL(0),
89 14 : fSSDZSThreshold(fgkSSDZSThresholdDefault),
90 14 : fNsigmas(fgkNsigmasDefault),
91 14 : fNcomps(fgkNcompsDefault),
92 14 : fGaus(),
93 14 : fN(0.),
94 14 : fT(300.)
95 70 : {
96 : // default constructor
97 14 : SetSPDBiasVoltageAll(fgkSPDBiasVoltageDefault);
98 14 : SetSPDThresholdsAll(fgkSPDThreshDefault,fgkSPDSigmaDefault);
99 14 : SetSPDNoiseAll(0,0);
100 14 : SetGeVToCharge();
101 14 : SetDistanceOverVoltage();
102 28 : SetSPDCouplingOption(fgkSPDCouplingOptDefault);
103 14 : SetSPDSigmaDiffusionAsymmetry(fgkSPDEccDiffDefault);
104 14 : SetSDDElectronics();
105 14 : SetSDDDiffCoeff(fgkSDDDiffCoeffDefault,fgkSDDDiffCoeff1Default);
106 14 : SetSDDMaxAdc((Double_t)fgkSDDMaxAdcDefault);
107 14 : SetSSDCouplings(fgkSSDCouplingPRDefault,fgkSSDCouplingPLDefault,fgkSSDCouplingNRDefault,fgkSSDCouplingNLDefault);
108 14 : fSPDHitStrobe[0]=-1; // 100 ns before the collision time ( 300 ns readout strobe in total)
109 14 : fSPDHitStrobe[1]=2; // 200 ns after the collision time (300 ns readout strobe in total)
110 14 : fSPDFoStrobe[0]=0; // coincidence with collision time
111 14 : fSPDFoStrobe[1]=1; // 100 ns after the collision time
112 28 : }
113 : //______________________________________________________________________
114 : AliITSSimuParam::AliITSSimuParam(const AliITSSimuParam &simpar):
115 0 : TObject(),
116 0 : fGeVcharge(simpar.fGeVcharge),
117 0 : fDOverV(simpar.fDOverV),
118 : //fSPDBiasVoltage(simpar.fSPDBiasVoltage),
119 : //fSPDThresh(simpar.fSPDThresh),
120 : //fSPDSigma(simpar.fSPDSigma),
121 0 : fSPDCouplOpt(simpar.fSPDCouplOpt),
122 0 : fSPDCouplCol(simpar.fSPDCouplCol),
123 0 : fSPDCouplRow(simpar.fSPDCouplRow),
124 0 : fSPDEccDiff(simpar.fSPDEccDiff),
125 0 : fSPDLorentzDrift(simpar.fSPDLorentzDrift),
126 0 : fSPDLorentzHoleWeight(simpar.fSPDLorentzHoleWeight),
127 0 : fSPDAddNoisyFlag(simpar.fSPDAddNoisyFlag),
128 0 : fSPDRemoveDeadFlag(simpar.fSPDRemoveDeadFlag),
129 0 : fSDDElectronics(simpar.fSDDElectronics),
130 0 : fSDDDiffCoeff(simpar.fSDDDiffCoeff),
131 0 : fSDDDiffCoeff1(simpar.fSDDDiffCoeff1),
132 0 : fSDDJitterError(simpar.fSDDJitterError),
133 0 : fSDDDynamicRange(simpar.fSDDDynamicRange),
134 0 : fSDDMaxAdc(simpar.fSDDMaxAdc),
135 0 : fSDDChargeLoss(simpar.fSDDChargeLoss),
136 0 : fSDDTrigDelay(simpar.fSDDTrigDelay),
137 0 : fSDDMapPrec(simpar.fSDDMapPrec),
138 0 : fSDDkeVtoADC(simpar.fSDDkeVtoADC),
139 0 : fSDDRawFormat(simpar.fSDDRawFormat),
140 0 : fSSDLorentzDrift(simpar.fSSDLorentzDrift),
141 0 : fSSDCouplingPR(simpar.fSSDCouplingPR),
142 0 : fSSDCouplingPL(simpar.fSSDCouplingPL),
143 0 : fSSDCouplingNR(simpar.fSSDCouplingNR),
144 0 : fSSDCouplingNL(simpar.fSSDCouplingNL),
145 0 : fSSDZSThreshold(simpar.fSSDZSThreshold),
146 0 : fNsigmas(simpar.fNsigmas),
147 0 : fNcomps(simpar.fNcomps),
148 0 : fGaus(),
149 0 : fN(simpar.fN),
150 0 : fT(simpar.fT){
151 : // copy constructor
152 0 : for (Int_t i=0;i<240;i++) {
153 0 : fSPDBiasVoltage[i]=simpar.fSPDBiasVoltage[i];
154 0 : fSPDThresh[i]=simpar.fSPDThresh[i];
155 0 : fSPDSigma[i]=simpar.fSPDSigma[i];
156 0 : fSPDNoise[i]=simpar.fSPDNoise[i];
157 0 : fSPDBaseline[i]=simpar.fSPDBaseline[i];
158 : }
159 0 : for (Int_t j=0; j<2; j++){
160 0 : fSPDHitStrobe[j]=simpar.fSPDHitStrobe[j];
161 0 : fSPDFoStrobe[j]=simpar.fSPDFoStrobe[j];
162 : }
163 0 : }
164 :
165 : //______________________________________________________________________
166 : AliITSSimuParam& AliITSSimuParam::operator=(const AliITSSimuParam& source){
167 : // Assignment operator.
168 0 : this->~AliITSSimuParam();
169 0 : new(this) AliITSSimuParam(source);
170 0 : return *this;
171 :
172 0 : }
173 :
174 :
175 : //______________________________________________________________________
176 84 : AliITSSimuParam::~AliITSSimuParam() {
177 : // destructor
178 16 : if(fGaus) delete fGaus;
179 42 : }
180 : //________________________________________________________________________
181 : void AliITSSimuParam::SetNLookUp(Int_t p1){
182 : // Set number of sigmas over which cluster disintegration is performed
183 2 : fNcomps=p1;
184 1 : if (fGaus) delete fGaus;
185 2 : fGaus = new TArrayF(fNcomps+1);
186 246 : for(Int_t i=0; i<=fNcomps; i++) {
187 122 : Float_t x = -fNsigmas + (2.*i*fNsigmas)/(fNcomps-1);
188 122 : (*fGaus)[i] = exp(-((x*x)/2));
189 : }
190 1 : }
191 : //________________________________________________________________________
192 : void AliITSSimuParam::PrintParameters() const{
193 : // Dump all parameters
194 0 : printf("GeVToCharge = %G\n",fGeVcharge);
195 0 : printf("DistanveOverVoltage = %f \n",fDOverV);
196 0 : printf("\n");
197 0 : printf("===== SPD parameters =====\n");
198 0 : printf("Bias Voltage = %f \n",fSPDBiasVoltage[0]);
199 0 : printf("Threshold and sigma = %f %f\n",fSPDThresh[0],fSPDSigma[0]);
200 0 : printf("Coupling Option = %s\n",fSPDCouplOpt.Data());
201 0 : printf("Coupling value (column) = %f\n",fSPDCouplCol);
202 0 : printf("Coupling value (row) = %f\n",fSPDCouplRow);
203 0 : printf("Eccentricity in diffusion = %f\n",fSPDEccDiff);
204 0 : printf("Flag to add Lorentz Drift = %d\n",fSPDLorentzDrift);
205 0 : printf("Weight of Holes in Lor.Drift = %f\n",fSPDLorentzHoleWeight);
206 0 : printf("Flag to add noisy = %d\n",fSPDAddNoisyFlag);
207 0 : printf("Flag to remove dead = %d\n",fSPDRemoveDeadFlag);
208 0 : printf("Hit Strobe params = %d %d\n",fSPDHitStrobe[0],fSPDHitStrobe[1]);
209 0 : printf("FO Strobe params = %d %d\n",fSPDFoStrobe[0],fSPDFoStrobe[1]);
210 0 : printf("\n");
211 0 : printf("===== SDD parameters =====\n");
212 0 : printf("Electronic chips = %d\n",fSDDElectronics);
213 0 : printf("Diffusion Coefficients = %f %f\n",fSDDDiffCoeff,fSDDDiffCoeff1);
214 0 : printf("Jitter Error = %f um\n",fSDDJitterError);
215 0 : printf("Dynamic Range = %f\n",fSDDDynamicRange);
216 0 : printf("Max. ADC = %f\n",fSDDMaxAdc);
217 0 : printf("Charge Loss = %f\n",fSDDChargeLoss);
218 0 : printf("Trigger Delay (ns) = %f\n",fSDDTrigDelay);
219 0 : printf("Smear from map (um) = %f\n",fSDDMapPrec);
220 0 : printf("keV->ADC conv. fact. = %f\n",fSDDkeVtoADC);
221 0 : printf("Raw Data Format = %d\n",fSDDRawFormat);
222 0 : printf("\n");
223 0 : printf("===== SSD parameters =====\n");
224 0 : printf("Flag to add Lorentz Drift = %d\n",fSSDLorentzDrift);
225 0 : printf("Coupling PR = %f\n",fSSDCouplingPR);
226 0 : printf("Coupling PL = %f\n",fSSDCouplingPL);
227 0 : printf("Coupling NR = %f\n",fSSDCouplingNR);
228 0 : printf("Coupling NL = %f\n",fSSDCouplingNL);
229 0 : printf("Zero Supp threshold = %d\n",fSSDZSThreshold);
230 0 : }
231 : //______________________________________________________________________
232 : Double_t AliITSSimuParam::MobilityElectronSiEmp() const {
233 : // Computes the electron mobility in cm^2/volt-sec. Taken from SILVACO
234 : // International ATLAS II, 2D Device Simulation Framework, User Manual
235 : // Chapter 5 Equation 5-6. An empirical function for low-field mobiliity
236 : // in silicon at different tempeatures.
237 : // Inputs:
238 : // none.
239 : // Output:
240 : // none.
241 : // Return:
242 : // The Mobility of electrons in Si at a give temprature and impurity
243 : // concentration. [cm^2/Volt-sec]
244 : const Double_t km0 = 55.24; // cm^2/Volt-sec
245 : const Double_t km1 = 7.12E+08; // cm^2 (degree K)^2.3 / Volt-sec
246 : const Double_t kN0 = 1.072E17; // #/cm^3
247 : const Double_t kT0 = 300.; // degree K.
248 : const Double_t keT0 = -2.3; // Power of Temp.
249 : const Double_t keT1 = -3.8; // Power of Temp.
250 : const Double_t keN = 0.73; // Power of Dopent Consentrations
251 : Double_t m;
252 0 : Double_t tT = fT,nN = fN;
253 :
254 0 : if(nN<=0.0){ // Simple case.
255 0 : if(tT==300.) return 1350.0; // From Table 5-1 at consentration 1.0E14.
256 0 : m = km1*TMath::Power(tT,keT0);
257 0 : return m;
258 : } // if nN<=0.0
259 0 : m = km1*TMath::Power(tT,keT0) - km0;
260 0 : m /= 1.0 + TMath::Power(tT/kT0,keT1)*TMath::Power(nN/kN0,keN);
261 0 : m += km0;
262 0 : return m;
263 0 : }
264 : //______________________________________________________________________
265 : Double_t AliITSSimuParam::MobilityHoleSiEmp() const {
266 : // Computes the Hole mobility in cm^2/volt-sec. Taken from SILVACO
267 : // International ATLAS II, 2D Device Simulation Framework, User Manual
268 : // Chapter 5 Equation 5-7 An empirical function for low-field mobiliity
269 : // in silicon at different tempeatures.
270 : // Inputs:
271 : // none.
272 : // Output:
273 : // none.
274 : // Return:
275 : // The Mobility of Hole in Si at a give temprature and impurity
276 : // concentration. [cm^2/Volt-sec]
277 : const Double_t km0a = 49.74; // cm^2/Volt-sec
278 : const Double_t km0b = 49.70; // cm^2/Volt-sec
279 : const Double_t km1 = 1.35E+08; // cm^2 (degree K)^2.3 / Volt-sec
280 : const Double_t kN0 = 1.606E17; // #/cm^3
281 : const Double_t kT0 = 300.; // degree K.
282 : const Double_t keT0 = -2.2; // Power of Temp.
283 : const Double_t keT1 = -3.7; // Power of Temp.
284 : const Double_t keN = 0.70; // Power of Dopent Consentrations
285 : Double_t m;
286 0 : Double_t tT = fT,nN = fN;
287 :
288 0 : if(nN<=0.0){ // Simple case.
289 0 : if(tT==300.) return 495.0; // From Table 5-1 at consentration 1.0E14.
290 0 : m = km1*TMath::Power(tT,keT0) + km0a-km0b;
291 0 : return m;
292 : } // if nN<=0.0
293 0 : m = km1*TMath::Power(tT,keT0) - km0b;
294 0 : m /= 1.0 + TMath::Power(tT/kT0,keT1)*TMath::Power(nN/kN0,keN);
295 0 : m += km0a;
296 0 : return m;
297 0 : }
298 : //______________________________________________________________________
299 : Double_t AliITSSimuParam::DiffusionCoefficientElectron() const {
300 : // Computes the Diffusion coefficient for electrons in cm^2/sec. Taken
301 : // from SILVACO International ATLAS II, 2D Device Simulation Framework,
302 : // User Manual Chapter 5 Equation 5-53. Einstein relations for diffusion
303 : // coefficient. Note: 1 cm^2/sec = 10 microns^2/nanosec.
304 : // Inputs:
305 : // none.
306 : // Output:
307 : // none.
308 : // Return:
309 : // The Diffusion Coefficient of electrons in Si at a give temprature
310 : // and impurity concentration. [cm^2/sec]
311 : // const Double_t kb = 1.3806503E-23; // Joules/degree K
312 : // const Double_t qe = 1.60217646E-19; // Coulumbs.
313 : const Double_t kbqe = 8.617342312E-5; // Volt/degree K
314 0 : Double_t m = MobilityElectronSiEmp();
315 0 : Double_t tT = fT;
316 :
317 0 : return m*kbqe*tT; // [cm^2/sec]
318 : }
319 : //______________________________________________________________________
320 : Double_t AliITSSimuParam::DiffusionCoefficientHole() const {
321 : // Computes the Diffusion coefficient for Holes in cm^2/sec. Taken
322 : // from SILVACO International ATLAS II, 2D Device Simulation Framework,
323 : // User Manual Chapter 5 Equation 5-53. Einstein relations for diffusion
324 : // coefficient. Note: 1 cm^2/sec = 10 microns^2/nanosec.
325 : // Inputs:
326 : // none.
327 : // Output:
328 : // none.
329 : // Return:
330 : // The Defusion Coefficient of Hole in Si at a give temprature and
331 : // impurity concentration. [cm^2/sec]
332 : // and impurity concentration. [cm^2/sec]
333 : // const Double_t kb = 1.3806503E-23; // Joules/degree K
334 : // const Double_t qe = 1.60217646E-19; // Coulumbs.
335 : const Double_t kbqe = 8.617342312E-5; // Volt/degree K
336 0 : Double_t m = MobilityHoleSiEmp();
337 0 : Double_t tT = fT;
338 :
339 0 : return m*kbqe*tT; // [cm^2/sec]
340 : }
341 : //______________________________________________________________________
342 : Double_t AliITSSimuParam::LorentzAngleHole(Double_t B) const {
343 : // Computes the Lorentz angle for electrons in Si
344 : // Input: magnetic Field in KGauss
345 : // Output: Lorentz angle in radians (positive if Bz is positive)
346 : // Main Reference: NIM A 497 (2003) 389–396.
347 : // "An algorithm for calculating the Lorentz angle in silicon detectors", V. Bartsch et al.
348 : //
349 : const Double_t krH=0.70; // Hall scattering factor for Hole
350 : const Double_t kT0 = 300.; // reference Temperature (degree K).
351 : const Double_t kmulow0 = 470.5; // cm^2/Volt-sec
352 : const Double_t keT0 = -2.5; // Power of Temp.
353 : const Double_t beta0 = 1.213; // beta coeff. at T0=300K
354 : const Double_t keT1 = 0.17; // Power of Temp. for beta
355 : const Double_t kvsat0 = 8.37E+06; // saturated velocity at T0=300K (cm/sec)
356 : const Double_t keT2 = 0.52; // Power of Temp. for vsat
357 8 : Double_t tT = fT;
358 4 : Double_t eE= 1./fDOverV;
359 4 : Double_t muLow=kmulow0*TMath::Power(tT/kT0,keT0);
360 4 : Double_t beta=beta0*TMath::Power(tT/kT0,keT1);
361 4 : Double_t vsat=kvsat0*TMath::Power(tT/kT0,keT2);
362 4 : Double_t mu=muLow/TMath::Power(1+TMath::Power(muLow*eE/vsat,beta),1/beta);
363 4 : Double_t angle=TMath::ATan(krH*mu*B*1.E-05); // Conversion Factor
364 4 : return angle;
365 : }
366 : //______________________________________________________________________
367 : Double_t AliITSSimuParam::LorentzAngleElectron(Double_t B) const {
368 : // Computes the Lorentz angle for electrons in Si
369 : // Input: magnetic Field in KGauss
370 : // Output: Lorentz angle in radians (positive if Bz is positive)
371 : // Main Reference: NIM A 497 (2003) 389–396.
372 : // "An algorithm for calculating the Lorentz angle in silicon detectors", V. Bartsch et al.
373 : //
374 : const Double_t krH=1.15; // Hall scattering factor for Electron
375 : const Double_t kT0 = 300.; // reference Temperature (degree K).
376 : const Double_t kmulow0 = 1417.0; // cm^2/Volt-sec
377 : const Double_t keT0 = -2.2; // Power of Temp.
378 : const Double_t beta0 = 1.109; // beta coeff. at T0=300K
379 : const Double_t keT1 = 0.66; // Power of Temp. for beta
380 : const Double_t kvsat0 = 1.07E+07; // saturated velocity at T0=300K (cm/sec)
381 : const Double_t keT2 = 0.87; // Power of Temp. for vsat
382 8 : Double_t tT = fT;
383 4 : Double_t eE= 1./fDOverV;
384 4 : Double_t muLow=kmulow0*TMath::Power(tT/kT0,keT0);
385 4 : Double_t beta=beta0*TMath::Power(tT/kT0,keT1);
386 4 : Double_t vsat=kvsat0*TMath::Power(tT/kT0,keT2);
387 4 : Double_t mu=muLow/TMath::Power(1+TMath::Power(muLow*eE/vsat,beta),1/beta);
388 4 : Double_t angle=TMath::ATan(krH*mu*B*1.E-05);
389 4 : return angle;
390 : }
391 : //______________________________________________________________________
392 : Double_t AliITSSimuParam::SpeedElectron() const {
393 : // Computes the average speed for electrons in Si under the low-field
394 : // approximation. [cm/sec].
395 : // Inputs:
396 : // none.
397 : // Output:
398 : // none.
399 : // Return:
400 : // The speed the holes are traveling at due to the low field applied.
401 : // [cm/sec]
402 0 : Double_t m = MobilityElectronSiEmp();
403 :
404 0 : return m/fDOverV; // [cm/sec]
405 : }
406 : //______________________________________________________________________
407 : Double_t AliITSSimuParam::SpeedHole() const {
408 : // Computes the average speed for Holes in Si under the low-field
409 : // approximation.[cm/sec].
410 : // Inputs:
411 : // none.
412 : // Output:
413 : // none.
414 : // Return:
415 : // The speed the holes are traveling at due to the low field applied.
416 : // [cm/sec]
417 0 : Double_t m = MobilityHoleSiEmp();
418 :
419 0 : return m/fDOverV; // [cm/sec]
420 : }
421 : //______________________________________________________________________
422 : Double_t AliITSSimuParam::SigmaDiffusion3D(Double_t l) const {
423 : // Returns the Gaussian sigma^2 == <x^2+y^2+z^2> [cm^2] due to the
424 : // defusion of electrons or holes through a distance l [cm] caused
425 : // by an applied voltage v [volt] through a distance d [cm] in any
426 : // material at a temperature T [degree K]. The sigma diffusion when
427 : // expressed in terms of the distance over which the diffusion
428 : // occures, l=time/speed, is independent of the mobility and therefore
429 : // the properties of the material. The charge distributions is given by
430 : // n = exp(-r^2/4Dt)/(4piDt)^1.5. From this <r^2> = 6Dt where D=mkT/e
431 : // (m==mobility, k==Boltzman's constant, T==temparature, e==electric
432 : // charge. and vel=m*v/d. consiquently sigma^2=6kTdl/ev.
433 : // Inputs:
434 : // Double_t l Distance the charge has to travel.
435 : // Output:
436 : // none.
437 : // Return:
438 : // The Sigma due to the diffution of electrons. [cm]
439 : const Double_t kcon = 5.17040258E-04; // == 6k/e [J/col or volts]
440 :
441 0 : return TMath::Sqrt(kcon*fT*fDOverV*l); // [cm]
442 : }
443 : //______________________________________________________________________
444 : Double_t AliITSSimuParam::SigmaDiffusion2D(Double_t l) const {
445 : // Returns the Gaussian sigma^2 == <x^2+z^2> [cm^2] due to the defusion
446 : // of electrons or holes through a distance l [cm] caused by an applied
447 : // voltage v [volt] through a distance d [cm] in any material at a
448 : // temperature T [degree K]. The sigma diffusion when expressed in terms
449 : // of the distance over which the diffusion occures, l=time/speed, is
450 : // independent of the mobility and therefore the properties of the
451 : // material. The charge distributions is given by
452 : // n = exp(-r^2/4Dt)/(4piDt)^1.5. From this <x^2+z^2> = 4Dt where D=mkT/e
453 : // (m==mobility, k==Boltzman's constant, T==temparature, e==electric
454 : // charge. and vel=m*v/d. consiquently sigma^2=4kTdl/ev.
455 : // Inputs:
456 : // Double_t l Distance the charge has to travel.
457 : // Output:
458 : // none.
459 : // Return:
460 : // The Sigma due to the diffution of electrons. [cm]
461 : const Double_t kcon = 3.446935053E-04; // == 4k/e [J/col or volts]
462 :
463 0 : return TMath::Sqrt(kcon*fT*fDOverV*l); // [cm]
464 : }
465 : //______________________________________________________________________
466 : Double_t AliITSSimuParam::SigmaDiffusion1D(Double_t l) const {
467 : // Returns the Gaussian sigma^2 == <x^2> [cm^2] due to the defusion
468 : // of electrons or holes through a distance l [cm] caused by an applied
469 : // voltage v [volt] through a distance d [cm] in any material at a
470 : // temperature T [degree K]. The sigma diffusion when expressed in terms
471 : // of the distance over which the diffusion occures, l=time/speed, is
472 : // independent of the mobility and therefore the properties of the
473 : // material. The charge distributions is given by
474 : // n = exp(-r^2/4Dt)/(4piDt)^1.5. From this <r^2> = 2Dt where D=mkT/e
475 : // (m==mobility, k==Boltzman's constant, T==temparature, e==electric
476 : // charge. and vel=m*v/d. consiquently sigma^2=2kTdl/ev.
477 : // Inputs:
478 : // Double_t l Distance the charge has to travel.
479 : // Output:
480 : // none.
481 : // Return:
482 : // The Sigma due to the diffution of electrons. [cm]
483 : const Double_t kcon = 1.723467527E-04; // == 2k/e [J/col or volts]
484 :
485 2360 : return TMath::Sqrt(kcon*fT*fDOverV*l); // [cm]
486 : }
487 : //----------------------------------------------------------------------
488 : Double_t AliITSSimuParam::DepletedRegionThicknessA(Double_t dopCons,
489 : Double_t voltage,
490 : Double_t elecCharge,
491 : Double_t voltBuiltIn)const{
492 : // Computes the thickness of the depleted region in Si due to the
493 : // application of an external bias voltage. From the Particle Data
494 : // Book, 28.8 Silicon semiconductor detectors equation 28.19 (2004)
495 : // Physics Letters B "Review of Particle Physics" Volume 592, Issue 1-4
496 : // July 15 2004, ISSN 0370-2693 page 263. First equation.
497 : // Inputs:
498 : // Double_t dopCons "N" doping concentration
499 : // Double_t voltage "V" external bias voltage
500 : // Double_t elecCharge "e" electronic charge
501 : // Double_t voltBuiltIn=0.5 "V_bi" "built-in" Voltage (~0.5V for
502 : // resistivities typically used in detectors)
503 : // Output:
504 : // none.
505 : // Return:
506 : // The thickness of the depleted region
507 :
508 0 : return TMath::Sqrt(2.0*(voltage+voltBuiltIn)/(dopCons*elecCharge));
509 : }
510 : //----------------------------------------------------------------------
511 : Double_t AliITSSimuParam::DepletedRegionThicknessB(Double_t resist,
512 : Double_t voltage,
513 : Double_t mobility,
514 : Double_t voltBuiltIn,
515 : Double_t dielConst)const{
516 : // Computes the thickness of the depleted region in Si due to the
517 : // application of an external bias voltage. From the Particle Data
518 : // Book, 28.8 Silicon semiconductor detectors equation 28.19 (2004)
519 : // Physics Letters B "Review of Particle Physics" Volume 592, Issue 1-4
520 : // July 15 2004, ISSN 0370-2693 page 263. Second Equation.
521 : // Inputs:
522 : // Double_t resist "rho" resistivity (typically 1-10 kOhm cm)
523 : // Double_t voltage "V" external bias voltage
524 : // Double_t mobility "mu" charge carrier mobility
525 : // (electons 1350, holes 450 cm^2/V/s)
526 : // Double_t voltBuiltIn=0.5 "V_bi" "built-in" Voltage (~0.5V for
527 : // resistivities typically used in detectors)
528 : // Double_t dielConst=1.E-12 "epsilon" dielectric constant = 11.9 *
529 : // (permittivity of free space) or ~ 1 pF/cm
530 : // Output:
531 : // none.
532 : // Return:
533 : // The thickness of the depleted region
534 :
535 0 : return TMath::Sqrt(2.8*resist*mobility*dielConst*(voltage+voltBuiltIn));
536 : }
537 : //----------------------------------------------------------------------
538 : Double_t AliITSSimuParam::ReverseBiasCurrent(Double_t temp,
539 : Double_t revBiasCurT1,
540 : Double_t tempT1,
541 : Double_t energy)const{
542 : // Computes the temperature dependance of the reverse bias current
543 : // of Si detectors. From the Particle Data
544 : // Book, 28.8 Silicon semiconductor detectors equation 28.21 (2004)
545 : // Physics Letters B "Review of Particle Physics" Volume 592, Issue 1-4
546 : // July 15 2004, ISSN 0370-2693 page 263.
547 : // Inputs:
548 : // Double_t temp The temperature at which the current is wanted
549 : // Double_t revBiasCurT1 The reference bias current at temp T1
550 : // Double_t tempT1 The temperature correstponding to revBiasCurT1
551 : // Double_t energy=1.2 Some energy [eV]
552 : // Output:
553 : // none.
554 : // Return:
555 : // The reverse bias current at the tempeature temp.
556 : const Double_t kBoltz = 8.617343E-5; //[eV/K]
557 :
558 0 : return revBiasCurT1*(temp*temp/(tempT1*tempT1))*
559 0 : TMath::Exp(-0.5*energy*(tempT1-temp)/(kBoltz*tempT1*temp));
560 : }
561 : //______________________________________________________________________
562 : void AliITSSimuParam::SPDThresholds(const Int_t mod, Double_t& thresh, Double_t& sigma) const {
563 : // Get SPD threshold values
564 78667818 : if(mod<0 || mod>239) {
565 0 : thresh=0;
566 0 : sigma=0;
567 0 : return;
568 : }
569 39333909 : thresh=fSPDThresh[mod];
570 39333909 : sigma=fSPDSigma[mod];
571 39333909 : return;
572 39333909 : }
573 : //_______________________________________________________________________
574 : void AliITSSimuParam::SPDNoise(const Int_t mod,Double_t &noise, Double_t &baseline) const {
575 : //Get SPD noise and baseline values
576 0 : if(mod<0 || mod>239) {
577 0 : noise=0;
578 0 : baseline=0;
579 0 : return;
580 : }
581 0 : noise=fSPDNoise[mod];
582 0 : baseline=fSPDBaseline[mod];
583 0 : return;
584 0 : }
585 :
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