Properly initialise pointers
[u/mrichter/AliRoot.git] / RICH / Opticals.h
CommitLineData
d48cca74 1#ifdef __CINT__
2void Opticals()
3{
4 gROOT->Reset();
5#endif
6 int i;
7 const Int_t kNbins=26;
8 Float_t aPckov[kNbins];
9 for(i=0;i<kNbins;i++){ //Photons energy intervals
10 aPckov[i]=(Float_t(i)*0.1+5.5)*1e-9;
11 }
12
13 Float_t aIndexFreon[kNbins];
14 Float_t aIndexQuartz[kNbins];
15 Float_t aIndexOpaqueQuartz[kNbins];
16 Float_t aIndexCH4[kNbins];
17 Float_t aIndexGrid[kNbins];
18
19 Float_t e1= 10.666;Float_t e2= 18.125; Float_t f1= 46.411; Float_t f2= 228.71;
20 for (i=0;i<kNbins;i++){
21 aIndexFreon[i] = aPckov[i] * .0172 * 1e9 + 1.177;
22 Float_t ene=aPckov[i]*1e9;
23 Float_t a=f1/(e1*e1 - ene*ene);
24 Float_t b=f2/(e2*e2 - ene*ene);
25 aIndexQuartz[i] = TMath::Sqrt(1. + a + b );
26 aIndexOpaqueQuartz[i] =1;
27 aIndexCH4[i] =1.000444;
28 aIndexGrid[i] =1;
29 }
30
31 Float_t aAbsFreon[kNbins]={179.0987, 179.0987, 179.0987, 179.0987, 179.0987,
32 179.0987, 179.0987, 179.0987, 179.0987, 142.9206,
33 56.64957, 25.58622, 13.95293, 12.03905, 10.42953,
34 8.804196, 7.069031, 4.461292, 2.028366, 1.293013,
35 0.577267, 0.40746, 0.334964, 0.0, 0.0,
36 0};
37
38
39 Float_t aAbsQuartz[kNbins]={105.8, 65.52, 48.58, 42.85, 35.79,
40 31.262, 28.598, 27.527, 25.007, 22.815,
41 21.004, 19.266, 17.525, 15.878, 14.177,
42 11.719, 9.282, 6.62, 4.0925, 2.601,
43 1.149, 0.667, 0.3627, 0.192, 0.1497,
44 0.10857};
45
46 Float_t aAbsOpaqueQuartz[kNbins];
47 Float_t aAbsCH4[kNbins];
48 Float_t aAbsGrid[kNbins];
49 Float_t aAbsCsI[kNbins];
50 for (i=0;i<kNbins;i++){
51 aAbsCH4[i] =AbsoCH4(aPckov[i]*1e9);
52 aAbsOpaqueQuartz[i]=1e-5;
53 aAbsCsI[i] =1e-4;
54 aAbsGrid[i] =1e-4;
55 }
56
57 Float_t aQeCsI[kNbins] = {0.000199999995, 0.000600000028, 0.000699999975, 0.00499999989, 0.00749999983,
58 0.010125, 0.0242999997, 0.0405000001, 0.0688500032, 0.105299994,
59 0.121500008, 0.141749993, 0.157949999, 0.162, 0.166050002,
60 0.167669997, 0.174299985, 0.176789999, 0.179279998, 0.182599992,
61 0.18592, 0.187579989, 0.189239994, 0.190899998, 0.207499996,
62 0.215799987};
63 Float_t aQeAll[kNbins];
64 for(i=0;i<kNbins;i++){
65 aQeCsI[i]/= (1.0-Fresnel(aPckov[i]*1e9,1.0,0)); //FRESNEL LOSS CORRECTION
66 aQeAll[i]=1; //QE for all other materials except for PC must be 1.
67 }
68
69
70#ifdef __CINT__
71
72
73//Freon, Quartz, Opaque Quartz,Methane,CsI,Grid
74 const Int_t kFreonMarker= 24; const Int_t kFreonColor=kRed;
75 const Int_t kCH4Marker= 25; const Int_t kCH4Color=kGreen;
76 const Int_t kSiO2Marker= 26; const Int_t kSiO2Color=kBlue;
77 const Int_t kCsIMarker = 2; const Int_t kCsIColor =kMagenta;
78
79 TCanvas *pC=new TCanvas("c1","RICH optics to check",800,900);
80
81 pC->Divide(2,2);
82
83 pC->cd(1);
84 TGraph *pAbsFreonGr=new TGraph(kNbins,aPckov,aAbsFreon);
85 pAbsFreonGr->SetMarkerStyle(kFreonMarker); pAbsFreonGr->SetMarkerColor(kFreonColor);
86 TGraph *pAbsSiO2Gr=new TGraph(kNbins,aPckov,aAbsQuartz);
87 pAbsSiO2Gr->SetMarkerStyle(kSiO2Marker); pAbsSiO2Gr->SetMarkerColor(kSiO2Color);
88 TMultiGraph *pAbsMG=new TMultiGraph();
89 TLegend *pAbsLegend=new TLegend(0.6,0.3,0.85,0.5);
90 pAbsMG->Add(pAbsFreonGr); pAbsLegend->AddEntry(pAbsFreonGr, "freon","p"); //1
91 pAbsMG->Add(pAbsSiO2Gr); pAbsLegend->AddEntry(pAbsSiO2Gr, "quartz","p"); //2
92 pAbsMG->Draw("APL");
93 pAbsMG->GetXaxis()->SetTitle("energy, GeV");
94 pAbsMG->GetYaxis()->SetTitle("absorption length, cm");
95 pAbsMG->Draw("APL");
96 pAbsLegend->Draw();
97
98
99 pC->cd(2);
100 TGraph *pIndexFreonGr=new TGraph(kNbins,aPckov,aIndexFreon);
101 pIndexFreonGr->SetMarkerStyle(kFreonMarker); pIndexFreonGr->SetMarkerColor(kFreonColor);
102 TGraph *pIndexSiO2Gr=new TGraph(kNbins,aPckov,aIndexQuartz);
103 pIndexSiO2Gr->SetMarkerStyle(kSiO2Marker); pIndexSiO2Gr->SetMarkerColor(kSiO2Color);
104 TGraph *pIndexCH4Gr=new TGraph(kNbins,aPckov,aIndexCH4);
105 pIndexCH4Gr->SetMarkerStyle(kCH4Marker); pIndexCH4Gr->SetMarkerColor(kCH4Color);
106 TMultiGraph *pIndexMG=new TMultiGraph();
107 TLegend *pIndexLegend=new TLegend(0.6,0.2,0.85,0.4);
108 pIndexMG->Add(pIndexFreonGr); pIndexLegend->AddEntry(pIndexFreonGr, "freon","p"); //1
109 pIndexMG->Add(pIndexSiO2Gr); pIndexLegend->AddEntry(pIndexSiO2Gr, "quartz","p");
110 pIndexMG->Add(pIndexCH4Gr); pIndexLegend->AddEntry(pIndexCH4Gr, "CH4","p");
111 pIndexMG->Draw("APL");
112 pIndexMG->GetXaxis()->SetTitle("energy, GeV");
113 pIndexMG->GetYaxis()->SetTitle("refraction index");
114 pIndexMG->Draw("APL");
115 pIndexLegend->Draw();
116
117 pC->cd(3);
118 TGraph *pAbsCH4Gr=new TGraph(kNbins,aPckov,aAbsCH4);
119 pAbsCH4Gr->SetMarkerStyle(kCH4Marker); pAbsCH4Gr->SetMarkerColor(kCH4Color);
120 pAbsCH4Gr->Draw("APL");
121 pAbsCH4Gr->GetXaxis()->SetTitle("energy, GeV");
122 pAbsCH4Gr->SetTitle("CH4 absorption length, cm");
123 pAbsCH4Gr->Draw("APL");
124
125
126 pC->cd(4);
127 TGraph *pQeCsIGr=new TGraph(kNbins,aPckov,aQeCsI);
128 pQeCsIGr->SetMarkerStyle(kCsIMarker); pQeCsIGr->SetMarkerColor(kCsIColor);
129 pQeCsIGr->Draw("APL");
130 pQeCsIGr->GetXaxis()->SetTitle("energy, GeV");
131 pQeCsIGr->SetTitle("CsI QE, all others are 1");
132 pQeCsIGr->Draw("APL");
133}//main
134
135Float_t AbsoCH4(Float_t x)
136{
137
138 //KLOSCH,SCH4(9),WL(9),EM(9),ALENGTH(31)
139 Float_t sch4[9] = {.12,.16,.23,.38,.86,2.8,7.9,28.,80.}; //MB X 10^22
140 //Float_t wl[9] = {153.,152.,151.,150.,149.,148.,147.,146.,145};
141 Float_t em[9] = {8.1,8.158,8.212,8.267,8.322,8.378,8.435,8.493,8.55};
142 const Float_t kLosch=2.686763E19; // LOSCHMIDT NUMBER IN CM-3
143 const Float_t kIgas1=100, kIgas2=0, kOxy=10., kWater=5., kPressure=750.,kTemperature=283.;
144 Float_t pn=kPressure/760.;
145 Float_t tn=kTemperature/273.16;
146
147
148// ------- METHANE CROSS SECTION -----------------
149// ASTROPH. J. 214, L47 (1978)
150
151 Float_t sm=0;
152 if (x<7.75)
153 sm=.06e-22;
154
155 if(x>=7.75 && x<=8.1)
156 {
157 Float_t c0=-1.655279e-1;
158 Float_t c1=6.307392e-2;
159 Float_t c2=-8.011441e-3;
160 Float_t c3=3.392126e-4;
161 sm=(c0+c1*x+c2*x*x+c3*x*x*x)*1.e-18;
162 }
163
164 if (x> 8.1)
165 {
166 Int_t j=0;
167 while (x<=em[j] && x>=em[j+1])
168 {
169 j++;
170 Float_t a=(sch4[j+1]-sch4[j])/(em[j+1]-em[j]);
171 sm=(sch4[j]+a*(x-em[j]))*1e-22;
172 }
173 }
174
175 Float_t dm=(kIgas1/100.)*(1.-((kOxy+kWater)/1.e6))*kLosch*pn/tn;
176 Float_t abslm=1./sm/dm;
177
178// ------- ISOBUTHANE CROSS SECTION --------------
179// i-C4H10 (ai) abs. length from curves in
180// Lu-McDonald paper for BARI RICH workshop .
181// -----------------------------------------------------------
182
183 Float_t ai;
184 Float_t absli;
185 if (kIgas2 != 0)
186 {
187 if (x<7.25)
188 ai=100000000.;
189
190 if(x>=7.25 && x<7.375)
191 ai=24.3;
192
193 if(x>=7.375)
194 ai=.0000000001;
195
196 Float_t si = 1./(ai*kLosch*273.16/293.); // ISOB. CRO.SEC.IN CM2
197 Float_t di=(kIgas2/100.)*(1.-((kOxy+kWater)/1.e6))*kLosch*pn/tn;
198 absli =1./si/di;
199 }
200 else
201 absli=1.e18;
202// ---------------------------------------------------------
203//
204// transmission of O2
205//
206// y= path in cm, x=energy in eV
207// so= cross section for UV absorption in cm2
208// do= O2 molecular density in cm-3
209// ---------------------------------------------------------
210
211 Float_t abslo;
212 Float_t so=0;
213 if(x>=6.0)
214 {
215 if(x>=6.0 && x<6.5)
216 {
217 so=3.392709e-13 * TMath::Exp(2.864104 *x);
218 so=so*1e-18;
219 }
220
221 if(x>=6.5 && x<7.0)
222 {
223 so=2.910039e-34 * TMath::Exp(10.3337*x);
224 so=so*1e-18;
225 }
226
227
228 if (x>=7.0)
229 {
230 Float_t a0=-73770.76;
231 Float_t a1=46190.69;
232 Float_t a2=-11475.44;
233 Float_t a3=1412.611;
234 Float_t a4=-86.07027;
235 Float_t a5=2.074234;
236 so= a0+(a1*x)+(a2*x*x)+(a3*x*x*x)+(a4*x*x*x*x)+(a5*x*x*x*x*x);
237 so=so*1e-18;
238 }
239
240 Float_t dox=(kOxy/1e6)*kLosch*pn/tn;
241 abslo=1./so/dox;
242 }
243 else
244 abslo=1.e18;
245// ---------------------------------------------------------
246//
247// transmission of H2O
248//
249// y= path in cm, x=energy in eV
250// sw= cross section for UV absorption in cm2
251// dw= H2O molecular density in cm-3
252// ---------------------------------------------------------
253
254 Float_t abslw;
255
256 Float_t b0=29231.65;
257 Float_t b1=-15807.74;
258 Float_t b2=3192.926;
259 Float_t b3=-285.4809;
260 Float_t b4=9.533944;
261
262 if(x>6.75)
263 {
264 Float_t sw= b0+(b1*x)+(b2*x*x)+(b3*x*x*x)+(b4*x*x*x*x);
265 sw=sw*1e-18;
266 Float_t dw=(kWater/1e6)*kLosch*pn/tn;
267 abslw=1./sw/dw;
268 }
269 else
270 abslw=1.e18;
271
272// ---------------------------------------------------------
273
274 Float_t alength=1./(1./abslm+1./absli+1./abslo+1./abslw);
275 return (alength);
276}//AbsoCH4
277
278
279Float_t Fresnel(Float_t ene,Float_t pdoti, Bool_t pola)
280{
281
282 //ENE(EV), PDOTI=COS(INC.ANG.), PDOTR=COS(POL.PLANE ROT.ANG.)
283
284 Float_t en[36] = {5.0,5.1,5.2,5.3,5.4,5.5,5.6,5.7,5.8,5.9,6.0,6.1,6.2,
285 6.3,6.4,6.5,6.6,6.7,6.8,6.9,7.0,7.1,7.2,7.3,7.4,7.5,7.6,7.7,
286 7.8,7.9,8.0,8.1,8.2,8.3,8.4,8.5};
287
288
289 Float_t csin[36] = {2.14,2.21,2.33,2.48,2.76,2.97,2.99,2.59,2.81,3.05,
290 2.86,2.53,2.55,2.66,2.79,2.96,3.18,3.05,2.84,2.81,2.38,2.11,
291 2.01,2.13,2.39,2.73,3.08,3.15,2.95,2.73,2.56,2.41,2.12,1.95,
292 1.72,1.53};
293
294 Float_t csik[36] = {0.,0.,0.,0.,0.,0.196,0.408,0.208,0.118,0.49,0.784,0.543,
295 0.424,0.404,0.371,0.514,0.922,1.102,1.139,1.376,1.461,1.253,0.878,
296 0.69,0.612,0.649,0.824,1.347,1.571,1.678,1.763,1.857,1.824,1.824,
297 1.714,1.498};
298 Float_t xe=ene;
299 Int_t j=Int_t(xe*10)-49;
300 Float_t cn=csin[j]+((csin[j+1]-csin[j])/0.1)*(xe-en[j]);
301 Float_t ck=csik[j]+((csik[j+1]-csik[j])/0.1)*(xe-en[j]);
302
303 //FORMULAE FROM HANDBOOK OF OPTICS, 33.23 OR
304 //W.R. HUNTER, J.O.S.A. 54 (1964),15 , J.O.S.A. 55(1965),1197
305
306 Float_t sinin=TMath::Sqrt(1-pdoti*pdoti);
307 Float_t tanin=sinin/pdoti;
308
309 Float_t c1=cn*cn-ck*ck-sinin*sinin;
310 Float_t c2=4*cn*cn*ck*ck;
311 Float_t aO=TMath::Sqrt(0.5*(TMath::Sqrt(c1*c1+c2)+c1));
312 Float_t b2=0.5*(TMath::Sqrt(c1*c1+c2)-c1);
313
314 Float_t rs=((aO-pdoti)*(aO-pdoti)+b2)/((aO+pdoti)*(aO+pdoti)+b2);
315 Float_t rp=rs*((aO-sinin*tanin)*(aO-sinin*tanin)+b2)/((aO+sinin*tanin)*(aO+sinin*tanin)+b2);
316
317
318 //CORRECTION FACTOR FOR SURFACE ROUGHNESS
319 //B.J. STAGG APPLIED OPTICS, 30(1991),4113
320
321 Float_t sigraf=18.;
322 Float_t lamb=1240/ene;
323 Float_t fresn;
324
325 Float_t rO=TMath::Exp(-(4*TMath::Pi()*pdoti*sigraf/lamb)*(4*TMath::Pi()*pdoti*sigraf/lamb));
326
327 if(pola)
328 {
329 Float_t pdotr=0.8; //DEGREE OF POLARIZATION : 1->P , -1->S
330 fresn=0.5*(rp*(1+pdotr)+rs*(1-pdotr));
331 }
332 else
333 fresn=0.5*(rp+rs);
334
335 fresn = fresn*rO;
336 return(fresn);
337}//Fresnel(...)
338#endif