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fcf95fc7 | 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 | // Calibration class for set:ITS // | |
19 | // Specific subdetector implementation is done in // | |
20 | // AliITSCalibrationSPD // | |
21 | // AliITSCalibrationSDD // | |
22 | // AliITSCalibrationSSD // | |
23 | ////////////////////////////////////////////////////// | |
24 | ||
25 | #include "Riostream.h" | |
26 | #include "AliITSCalibration.h" | |
27 | ||
28 | ClassImp(AliITSCalibration) | |
29 | ||
30 | //______________________________________________________________________ | |
31 | AliITSCalibration::AliITSCalibration(){ | |
32 | // Default Constructor | |
33 | ||
34 | fdv = 0.000375; // 300 microns and 80 volts. | |
35 | fN = 0.0; | |
36 | fT = 300.0; | |
37 | SetGeVToCharge(); | |
38 | fResponse = 0; | |
39 | } | |
40 | //______________________________________________________________________ | |
41 | AliITSCalibration::AliITSCalibration(Double_t thickness){ | |
42 | // Default Constructor | |
43 | ||
44 | fdv = thickness/80.0; // 80 volts. | |
45 | fN = 0.0; | |
46 | fT = 300.0; | |
47 | SetGeVToCharge(); | |
48 | fResponse = 0; | |
49 | } | |
50 | //______________________________________________________________________ | |
51 | AliITSCalibration::AliITSCalibration(const AliITSCalibration &ob) : TObject(ob) { | |
52 | // Copy constructor | |
53 | // Copies are not allowed. The method is protected to avoid misuse. | |
54 | Error("AliITSCalibration","Copy constructor not allowed\n"); | |
55 | } | |
56 | ||
57 | //______________________________________________________________________ | |
58 | AliITSCalibration& AliITSCalibration::operator=(const AliITSCalibration& /* ob */){ | |
59 | // Assignment operator | |
60 | // Assignment is not allowed. The method is protected to avoid misuse. | |
61 | Error("= operator","Assignment operator not allowed\n"); | |
62 | return *this; | |
63 | } | |
64 | ||
65 | //______________________________________________________________________ | |
66 | Double_t AliITSCalibration::MobilityElectronSiEmp() const { | |
67 | // Computes the electron mobility in cm^2/volt-sec. Taken from SILVACO | |
68 | // International ATLAS II, 2D Device Simulation Framework, User Manual | |
69 | // Chapter 5 Equation 5-6. An empirical function for low-field mobiliity | |
70 | // in silicon at different tempeatures. | |
71 | // Inputs: | |
72 | // none. | |
73 | // Output: | |
74 | // none. | |
75 | // Return: | |
76 | // The Mobility of electrons in Si at a give temprature and impurity | |
77 | // concentration. [cm^2/Volt-sec] | |
78 | const Double_t km0 = 55.24; // cm^2/Volt-sec | |
79 | const Double_t km1 = 7.12E+08; // cm^2 (degree K)^2.3 / Volt-sec | |
80 | const Double_t kN0 = 1.072E17; // #/cm^3 | |
81 | const Double_t kT0 = 300.; // degree K. | |
82 | const Double_t keT0 = -2.3; // Power of Temp. | |
83 | const Double_t keT1 = -3.8; // Power of Temp. | |
84 | const Double_t keN = 0.73; // Power of Dopent Consentrations | |
85 | Double_t m; | |
86 | Double_t tT = fT,nN = fN; | |
87 | ||
88 | if(nN<=0.0){ // Simple case. | |
89 | if(tT==300.) return 1350.0; // From Table 5-1 at consentration 1.0E14. | |
90 | m = km1*TMath::Power(tT,keT0); | |
91 | return m; | |
92 | } // if nN<=0.0 | |
93 | m = km1*TMath::Power(tT,keT0) - km0; | |
94 | m /= 1.0 + TMath::Power(tT/kT0,keT1)*TMath::Power(nN/kN0,keN); | |
95 | m += km0; | |
96 | return m; | |
97 | } | |
98 | //______________________________________________________________________ | |
99 | Double_t AliITSCalibration::MobilityHoleSiEmp() const { | |
100 | // Computes the Hole mobility in cm^2/volt-sec. Taken from SILVACO | |
101 | // International ATLAS II, 2D Device Simulation Framework, User Manual | |
102 | // Chapter 5 Equation 5-7 An empirical function for low-field mobiliity | |
103 | // in silicon at different tempeatures. | |
104 | // Inputs: | |
105 | // none. | |
106 | // Output: | |
107 | // none. | |
108 | // Return: | |
109 | // The Mobility of Hole in Si at a give temprature and impurity | |
110 | // concentration. [cm^2/Volt-sec] | |
111 | const Double_t km0a = 49.74; // cm^2/Volt-sec | |
112 | const Double_t km0b = 49.70; // cm^2/Volt-sec | |
113 | const Double_t km1 = 1.35E+08; // cm^2 (degree K)^2.3 / Volt-sec | |
114 | const Double_t kN0 = 1.606E17; // #/cm^3 | |
115 | const Double_t kT0 = 300.; // degree K. | |
116 | const Double_t keT0 = -2.2; // Power of Temp. | |
117 | const Double_t keT1 = -3.7; // Power of Temp. | |
118 | const Double_t keN = 0.70; // Power of Dopent Consentrations | |
119 | Double_t m; | |
120 | Double_t tT = fT,nN = fN; | |
121 | ||
122 | if(nN<=0.0){ // Simple case. | |
123 | if(tT==300.) return 495.0; // From Table 5-1 at consentration 1.0E14. | |
124 | m = km1*TMath::Power(tT,keT0) + km0a-km0b; | |
125 | return m; | |
126 | } // if nN<=0.0 | |
127 | m = km1*TMath::Power(tT,keT0) - km0b; | |
128 | m /= 1.0 + TMath::Power(tT/kT0,keT1)*TMath::Power(nN/kN0,keN); | |
129 | m += km0a; | |
130 | return m; | |
131 | } | |
132 | //______________________________________________________________________ | |
133 | Double_t AliITSCalibration::DiffusionCoefficientElectron() const { | |
134 | // Computes the Diffusion coefficient for electrons in cm^2/sec. Taken | |
135 | // from SILVACO International ATLAS II, 2D Device Simulation Framework, | |
136 | // User Manual Chapter 5 Equation 5-53. Einstein relations for diffusion | |
137 | // coefficient. Note: 1 cm^2/sec = 10 microns^2/nanosec. | |
138 | // Inputs: | |
139 | // none. | |
140 | // Output: | |
141 | // none. | |
142 | // Return: | |
143 | // The Diffusion Coefficient of electrons in Si at a give temprature | |
144 | // and impurity concentration. [cm^2/sec] | |
145 | // const Double_t kb = 1.3806503E-23; // Joules/degree K | |
146 | // const Double_t qe = 1.60217646E-19; // Coulumbs. | |
147 | const Double_t kbqe = 8.617342312E-5; // Volt/degree K | |
148 | Double_t m = MobilityElectronSiEmp(); | |
149 | Double_t tT = fT; | |
150 | ||
151 | return m*kbqe*tT; // [cm^2/sec] | |
152 | } | |
153 | //______________________________________________________________________ | |
154 | Double_t AliITSCalibration::DiffusionCoefficientHole() const { | |
155 | // Computes the Diffusion coefficient for Holes in cm^2/sec. Taken | |
156 | // from SILVACO International ATLAS II, 2D Device Simulation Framework, | |
157 | // User Manual Chapter 5 Equation 5-53. Einstein relations for diffusion | |
158 | // coefficient. Note: 1 cm^2/sec = 10 microns^2/nanosec. | |
159 | // Inputs: | |
160 | // none. | |
161 | // Output: | |
162 | // none. | |
163 | // Return: | |
164 | // The Defusion Coefficient of Hole in Si at a give temprature and | |
165 | // impurity concentration. [cm^2/sec] | |
166 | // and impurity concentration. [cm^2/sec] | |
167 | // const Double_t kb = 1.3806503E-23; // Joules/degree K | |
168 | // const Double_t qe = 1.60217646E-19; // Coulumbs. | |
169 | const Double_t kbqe = 8.617342312E-5; // Volt/degree K | |
170 | Double_t m = MobilityHoleSiEmp(); | |
171 | Double_t tT = fT; | |
172 | ||
173 | return m*kbqe*tT; // [cm^2/sec] | |
174 | } | |
175 | //______________________________________________________________________ | |
176 | Double_t AliITSCalibration::SpeedElectron() const { | |
177 | // Computes the average speed for electrons in Si under the low-field | |
178 | // approximation. [cm/sec]. | |
179 | // Inputs: | |
180 | // none. | |
181 | // Output: | |
182 | // none. | |
183 | // Return: | |
184 | // The speed the holes are traveling at due to the low field applied. | |
185 | // [cm/sec] | |
186 | Double_t m = MobilityElectronSiEmp(); | |
187 | ||
188 | return m/fdv; // [cm/sec] | |
189 | } | |
190 | //______________________________________________________________________ | |
191 | Double_t AliITSCalibration::SpeedHole() const { | |
192 | // Computes the average speed for Holes in Si under the low-field | |
193 | // approximation.[cm/sec]. | |
194 | // Inputs: | |
195 | // none. | |
196 | // Output: | |
197 | // none. | |
198 | // Return: | |
199 | // The speed the holes are traveling at due to the low field applied. | |
200 | // [cm/sec] | |
201 | Double_t m = MobilityHoleSiEmp(); | |
202 | ||
203 | return m/fdv; // [cm/sec] | |
204 | } | |
205 | //______________________________________________________________________ | |
206 | Double_t AliITSCalibration::SigmaDiffusion3D(Double_t l) const { | |
207 | // Returns the Gaussian sigma^2 == <x^2+y^2+z^2> [cm^2] due to the | |
208 | // defusion of electrons or holes through a distance l [cm] caused | |
209 | // by an applied voltage v [volt] through a distance d [cm] in any | |
210 | // material at a temperature T [degree K]. The sigma diffusion when | |
211 | // expressed in terms of the distance over which the diffusion | |
212 | // occures, l=time/speed, is independent of the mobility and therefore | |
213 | // the properties of the material. The charge distributions is given by | |
214 | // n = exp(-r^2/4Dt)/(4piDt)^1.5. From this <r^2> = 6Dt where D=mkT/e | |
215 | // (m==mobility, k==Boltzman's constant, T==temparature, e==electric | |
216 | // charge. and vel=m*v/d. consiquently sigma^2=6kTdl/ev. | |
217 | // Inputs: | |
218 | // Double_t l Distance the charge has to travel. | |
219 | // Output: | |
220 | // none. | |
221 | // Return: | |
222 | // The Sigma due to the diffution of electrons. [cm] | |
223 | const Double_t kcon = 5.17040258E-04; // == 6k/e [J/col or volts] | |
224 | ||
225 | return TMath::Sqrt(kcon*fT*fdv*l); // [cm] | |
226 | } | |
227 | //______________________________________________________________________ | |
228 | Double_t AliITSCalibration::SigmaDiffusion2D(Double_t l) const { | |
229 | // Returns the Gaussian sigma^2 == <x^2+z^2> [cm^2] due to the defusion | |
230 | // of electrons or holes through a distance l [cm] caused by an applied | |
231 | // voltage v [volt] through a distance d [cm] in any material at a | |
232 | // temperature T [degree K]. The sigma diffusion when expressed in terms | |
233 | // of the distance over which the diffusion occures, l=time/speed, is | |
234 | // independent of the mobility and therefore the properties of the | |
235 | // material. The charge distributions is given by | |
236 | // n = exp(-r^2/4Dt)/(4piDt)^1.5. From this <x^2+z^2> = 4Dt where D=mkT/e | |
237 | // (m==mobility, k==Boltzman's constant, T==temparature, e==electric | |
238 | // charge. and vel=m*v/d. consiquently sigma^2=4kTdl/ev. | |
239 | // Inputs: | |
240 | // Double_t l Distance the charge has to travel. | |
241 | // Output: | |
242 | // none. | |
243 | // Return: | |
244 | // The Sigma due to the diffution of electrons. [cm] | |
245 | const Double_t kcon = 3.446935053E-04; // == 4k/e [J/col or volts] | |
246 | ||
247 | return TMath::Sqrt(kcon*fT*fdv*l); // [cm] | |
248 | } | |
249 | //______________________________________________________________________ | |
250 | Double_t AliITSCalibration::SigmaDiffusion1D(Double_t l) const { | |
251 | // Returns the Gaussian sigma^2 == <x^2> [cm^2] due to the defusion | |
252 | // of electrons or holes through a distance l [cm] caused by an applied | |
253 | // voltage v [volt] through a distance d [cm] in any material at a | |
254 | // temperature T [degree K]. The sigma diffusion when expressed in terms | |
255 | // of the distance over which the diffusion occures, l=time/speed, is | |
256 | // independent of the mobility and therefore the properties of the | |
257 | // material. The charge distributions is given by | |
258 | // n = exp(-r^2/4Dt)/(4piDt)^1.5. From this <r^2> = 2Dt where D=mkT/e | |
259 | // (m==mobility, k==Boltzman's constant, T==temparature, e==electric | |
260 | // charge. and vel=m*v/d. consiquently sigma^2=2kTdl/ev. | |
261 | // Inputs: | |
262 | // Double_t l Distance the charge has to travel. | |
263 | // Output: | |
264 | // none. | |
265 | // Return: | |
266 | // The Sigma due to the diffution of electrons. [cm] | |
267 | const Double_t kcon = 1.723467527E-04; // == 2k/e [J/col or volts] | |
268 | ||
269 | return TMath::Sqrt(kcon*fT*fdv*l); // [cm] | |
270 | } | |
271 | //---------------------------------------------------------------------- | |
272 | Double_t AliITSCalibration::DepletedRegionThicknessA(Double_t dopCons, | |
273 | Double_t voltage, | |
274 | Double_t elecCharge, | |
275 | Double_t voltBuiltIn)const{ | |
276 | // Computes the thickness of the depleted region in Si due to the | |
277 | // application of an external bias voltage. From the Particle Data | |
278 | // Book, 28.8 Silicon semiconductor detectors equation 28.19 (2004) | |
279 | // Physics Letters B "Review of Particle Physics" Volume 592, Issue 1-4 | |
280 | // July 15 2004, ISSN 0370-2693 page 263. First equation. | |
281 | // Inputs: | |
282 | // Double_t dopCons "N" doping concentration | |
283 | // Double_t voltage "V" external bias voltage | |
284 | // Double_t elecCharge "e" electronic charge | |
285 | // Double_t voltBuiltIn=0.5 "V_bi" "built-in" Voltage (~0.5V for | |
286 | // resistivities typically used in detectors) | |
287 | // Output: | |
288 | // none. | |
289 | // Return: | |
290 | // The thickness of the depleted region | |
291 | ||
292 | return TMath::Sqrt(2.0*(voltage+voltBuiltIn)/(dopCons*elecCharge)); | |
293 | } | |
294 | //---------------------------------------------------------------------- | |
295 | Double_t AliITSCalibration::DepletedRegionThicknessB(Double_t resist, | |
296 | Double_t voltage, | |
297 | Double_t mobility, | |
298 | Double_t voltBuiltIn, | |
299 | Double_t dielConst)const{ | |
300 | // Computes the thickness of the depleted region in Si due to the | |
301 | // application of an external bias voltage. From the Particle Data | |
302 | // Book, 28.8 Silicon semiconductor detectors equation 28.19 (2004) | |
303 | // Physics Letters B "Review of Particle Physics" Volume 592, Issue 1-4 | |
304 | // July 15 2004, ISSN 0370-2693 page 263. Second Equation. | |
305 | // Inputs: | |
306 | // Double_t resist "rho" resistivity (typically 1-10 kOhm cm) | |
307 | // Double_t voltage "V" external bias voltage | |
308 | // Double_t mobility "mu" charge carrier mobility | |
309 | // (electons 1350, holes 450 cm^2/V/s) | |
310 | // Double_t voltBuiltIn=0.5 "V_bi" "built-in" Voltage (~0.5V for | |
311 | // resistivities typically used in detectors) | |
312 | // Double_t dielConst=1.E-12 "epsilon" dielectric constant = 11.9 * | |
313 | // (permittivity of free space) or ~ 1 pF/cm | |
314 | // Output: | |
315 | // none. | |
316 | // Return: | |
317 | // The thickness of the depleted region | |
318 | ||
319 | return TMath::Sqrt(2.8*resist*mobility*dielConst*(voltage+voltBuiltIn)); | |
320 | } | |
321 | //---------------------------------------------------------------------- | |
322 | Double_t AliITSCalibration::ReverseBiasCurrent(Double_t temp, | |
323 | Double_t revBiasCurT1, | |
324 | Double_t tempT1, | |
325 | Double_t energy)const{ | |
326 | // Computes the temperature dependance of the reverse bias current | |
327 | // of Si detectors. From the Particle Data | |
328 | // Book, 28.8 Silicon semiconductor detectors equation 28.21 (2004) | |
329 | // Physics Letters B "Review of Particle Physics" Volume 592, Issue 1-4 | |
330 | // July 15 2004, ISSN 0370-2693 page 263. | |
331 | // Inputs: | |
332 | // Double_t temp The temperature at which the current is wanted | |
333 | // Double_t revBiasCurT1 The reference bias current at temp T1 | |
334 | // Double_t tempT1 The temperature correstponding to revBiasCurT1 | |
335 | // Double_t energy=1.2 Some energy [eV] | |
336 | // Output: | |
337 | // none. | |
338 | // Return: | |
339 | // The reverse bias current at the tempeature temp. | |
340 | const Double_t kBoltz = 8.617343E-5; //[eV/K] | |
341 | ||
342 | return revBiasCurT1*(temp*temp/(tempT1*tempT1))* | |
343 | TMath::Exp(-0.5*energy*(tempT1-temp)/(kBoltz*tempT1*temp)); | |
344 | } | |
345 | //---------------------------------------------------------------------- | |
346 | void AliITSCalibration::Print(ostream *os) const { | |
347 | // Standard output format for this class. | |
348 | // Inputs: | |
349 | *os << fdv << " " << fN << " " << fT << " "; | |
350 | *os << fGeVcharge; | |
351 | // printf("%-10.6e %-10.6e %-10.6e %-10.6e \n",fdv,fN,fT,fGeVcharge); | |
352 | return; | |
353 | } | |
354 | //---------------------------------------------------------------------- | |
355 | void AliITSCalibration::Read(istream *is) { | |
356 | // Standard input format for this class. | |
357 | // Inputs: | |
358 | // ostream *is Pointer to the output stream | |
359 | // Outputs: | |
360 | // none: | |
361 | // Return: | |
362 | // none. | |
363 | ||
364 | *is >> fdv >> fN >> fT >> fGeVcharge; | |
365 | return; | |
366 | } | |
367 | //---------------------------------------------------------------------- | |
368 | ||
369 | ostream &operator<<(ostream &os,AliITSCalibration &p){ | |
370 | // Standard output streaming function. | |
371 | // Inputs: | |
372 | // ostream *os Pointer to the output stream | |
373 | // Outputs: | |
374 | // none: | |
375 | // Return: | |
376 | // none. | |
377 | ||
378 | p.Print(&os); | |
379 | return os; | |
380 | } | |
381 | ||
382 | //---------------------------------------------------------------------- | |
383 | istream &operator>>(istream &is,AliITSCalibration &r){ | |
384 | // Standard input streaming function. | |
385 | // Inputs: | |
386 | // ostream *os Pointer to the output stream | |
387 | // Outputs: | |
388 | // none: | |
389 | // Return: | |
390 | // none. | |
391 | ||
392 | r.Read(&is); | |
393 | return is; | |
394 | } | |
395 | //---------------------------------------------------------------------- |