]>
Commit | Line | Data |
---|---|---|
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 | /* $Id$ */ | |
17 | ||
18 | // Read beam halo background particles from a boundary source | |
19 | // Boundary source is in the LHCb format http://www.hep.manchester.ac.uk/u/robert/LHC_backgrounds/Note-MIBStudies.pdf | |
20 | // and has been provided by Robert Appleby | |
21 | // Author: andreas.morsch@cern.ch | |
22 | ||
23 | ||
24 | #include <stdlib.h> | |
25 | ||
26 | #include <TDatabasePDG.h> | |
27 | #include <TCanvas.h> | |
28 | #include <TGraph.h> | |
29 | #include <TPDGCode.h> | |
30 | #include <TSystem.h> | |
31 | ||
32 | #include "AliGenHalo.h" | |
33 | #include "AliRun.h" | |
34 | ||
35 | ClassImp(AliGenHalo) | |
36 | ||
37 | AliGenHalo::AliGenHalo() | |
38 | :AliGenerator(-1), | |
39 | fFile(0), | |
40 | fFileName(0), | |
41 | fSide(1), | |
42 | fRunPeriod(kY3D90), | |
43 | fTimePerEvent(1.e-4), | |
44 | fNskip(0), | |
45 | fZ1(0), | |
46 | fZ2(0), | |
47 | fG1(0), | |
48 | fG2(0), | |
49 | fGPASize(0), | |
50 | fLossID(0), | |
51 | fLossA(0), | |
52 | fPdg(0), | |
53 | fLossT0(0), | |
54 | fLossZ(0), | |
55 | fLossW(0), | |
56 | fXS(0), | |
57 | fYS(0), | |
58 | fZS(0), | |
59 | fDX(0), | |
60 | fDY(0), | |
61 | fEkin(0), | |
62 | fTS(0), | |
63 | fWS(0) | |
64 | { | |
65 | // Constructor | |
66 | ||
67 | fName = "Halo"; | |
68 | fTitle = "Halo from LHC Beam"; | |
69 | // | |
70 | // Read all particles | |
71 | fNpart = -1; | |
72 | SetAnalog(0); | |
73 | } | |
74 | ||
75 | AliGenHalo::AliGenHalo(Int_t npart) | |
76 | :AliGenerator(npart), | |
77 | fFile(0), | |
78 | fFileName(0), | |
79 | fSide(1), | |
80 | fRunPeriod(kY3D90), | |
81 | fTimePerEvent(1.e-4), | |
82 | fNskip(0), | |
83 | fZ1(0), | |
84 | fZ2(0), | |
85 | fG1(0), | |
86 | fG2(0), | |
87 | fGPASize(0), | |
88 | fLossID(0), | |
89 | fLossA(0), | |
90 | fPdg(0), | |
91 | fLossT0(0), | |
92 | fLossZ(0), | |
93 | fLossW(0), | |
94 | fXS(0), | |
95 | fYS(0), | |
96 | fZS(0), | |
97 | fDX(0), | |
98 | fDY(0), | |
99 | fEkin(0), | |
100 | fTS(0), | |
101 | fWS(0) | |
102 | { | |
103 | // Constructor | |
104 | fName = "Halo"; | |
105 | fTitle= "Halo from LHC Beam"; | |
106 | // | |
107 | fNpart = npart; | |
108 | // | |
109 | SetAnalog(0); | |
110 | } | |
111 | ||
112 | //____________________________________________________________ | |
113 | AliGenHalo::~AliGenHalo() | |
114 | { | |
115 | // Destructor | |
116 | } | |
117 | ||
118 | //____________________________________________________________ | |
119 | void AliGenHalo::Init() | |
120 | { | |
121 | // Initialisation | |
122 | fFile = fopen(fFileName,"r"); | |
123 | if (fFile) { | |
124 | printf("\n File %s opened for reading, %p ! \n ", fFileName.Data(), (void*)fFile); | |
125 | } else { | |
126 | printf("\n Opening of file %s failed, %p ! \n ", fFileName.Data(), (void*)fFile); | |
127 | } | |
128 | ||
129 | if (fNskip > 0) { | |
130 | // Skip the first fNskip events | |
131 | SkipEvents(); | |
132 | } | |
133 | // | |
134 | // | |
135 | // | |
136 | // Read file with gas pressure values | |
137 | char *name = 0; | |
138 | if (fRunPeriod < 5) { | |
139 | name = gSystem->ExpandPathName("$(ALICE_ROOT)/LHC/gasPressure.dat" ); | |
140 | fGPASize = 21; | |
141 | fG1 = new Float_t[fGPASize]; | |
142 | fG2 = new Float_t[fGPASize]; | |
143 | fZ1 = new Float_t[fGPASize]; | |
144 | fZ2 = new Float_t[fGPASize]; | |
145 | } else if (fRunPeriod == 5) { | |
146 | name = gSystem->ExpandPathName("$(ALICE_ROOT)/LHC/pressure_2003_startup.dat"); | |
147 | fGPASize = 18853; | |
148 | fG1 = new Float_t[fGPASize]; | |
149 | fZ1 = new Float_t[fGPASize]; | |
150 | } else if (fRunPeriod ==6) { | |
151 | name = gSystem->ExpandPathName("$(ALICE_ROOT)/LHC/pressure_2003_conditioned.dat"); | |
152 | fGPASize = 12719; | |
153 | fG1 = new Float_t[fGPASize]; | |
154 | fZ1 = new Float_t[fGPASize]; | |
155 | } else { | |
156 | Fatal("Init()", "No gas pressure file for given run period !"); | |
157 | } | |
158 | ||
159 | ||
160 | FILE* file = fopen(name, "r"); | |
161 | Float_t z; | |
162 | Int_t i; | |
163 | Float_t p[5]; | |
164 | ||
165 | const Float_t kCrossSection = 0.094e-28; // m^2 | |
166 | const Float_t kFlux = 1.e11 / 25.e-9; // protons/s | |
167 | Float_t pFlux[5] = {0.2, 0.2, 0.3, 0.3, 1.0}; | |
168 | ||
169 | if (fRunPeriod < 5) { | |
170 | // | |
171 | // Ring 1 | |
172 | // | |
173 | ||
174 | for (i = 0; i < fGPASize; i++) | |
175 | { | |
176 | fscanf(file, "%f %f %f %f %f %f", &z, &p[0], &p[1], &p[2] , &p[3], &p[4]); | |
177 | fG1[i] = p[fRunPeriod]; | |
178 | ||
179 | if (i > 0) { | |
180 | fZ1[i] = fZ1[i-1] + z; | |
181 | } else { | |
182 | fZ1[i] = 20.; | |
183 | } | |
184 | } | |
185 | // | |
186 | // Ring 2 | |
187 | // | |
188 | for (i = 0; i < fGPASize; i++) | |
189 | { | |
190 | fscanf(file, "%f %f %f %f %f %f", &z, &p[0], &p[1], &p[2] , &p[3], &p[4]); | |
191 | fG2[i] = p[fRunPeriod]; | |
192 | if (i > 0) { | |
193 | fZ2[i] = fZ2[i-1] + z; | |
194 | } else { | |
195 | fZ2[i] = 20.; | |
196 | } | |
197 | } | |
198 | // | |
199 | // Interaction rates | |
200 | // | |
201 | for (i = 0; i < fGPASize; i++) | |
202 | { | |
203 | fG1[i] = fG1[i] * kCrossSection * pFlux[fRunPeriod] * kFlux; // 1/m/s | |
204 | fG2[i] = fG2[i] * kCrossSection * pFlux[fRunPeriod] * kFlux; // 1/m/s | |
205 | } | |
206 | ||
207 | } else { | |
208 | for (i = 0; i < fGPASize; i++) | |
209 | { | |
210 | fscanf(file, "%f %e %e %e %e %e", &z, &p[0], &p[1], &p[2], &p[3], &p[4]); | |
211 | z /= 1000.; | |
212 | fG1[i] = p[4] * kCrossSection * kFlux; // 1/m/s | |
213 | // 1/3 of nominal intensity at startup | |
214 | if (fRunPeriod == kLHCPR674Startup) fG1[i] /= 3.; | |
215 | fZ1[i] = z; | |
216 | } | |
217 | } | |
218 | ||
219 | ||
220 | ||
221 | ||
222 | // | |
223 | // Transform into interaction rates | |
224 | // | |
225 | ||
226 | ||
227 | ||
228 | ||
229 | Float_t sum1 = 0.; | |
230 | Float_t sum2 = 0.; | |
231 | ||
232 | for (Int_t iz = 0; iz < 300; iz++) { | |
233 | Float_t zpos = 20. + iz * 1.; | |
234 | zpos *= 100; | |
235 | Float_t wgt1 = GasPressureWeight( zpos); | |
236 | Float_t wgt2 = GasPressureWeight(-zpos); | |
237 | sum1 += wgt1; | |
238 | sum2 += wgt2; | |
239 | } | |
240 | sum1/=250.; | |
241 | sum2/=250.; | |
242 | printf("\n %f %f \n \n", sum1, sum2); | |
243 | } | |
244 | ||
245 | //____________________________________________________________ | |
246 | void AliGenHalo::Generate() | |
247 | { | |
248 | // Generate by reading particles from input file | |
249 | ||
250 | Float_t polar[3]= {0., 0., 0.}; | |
251 | Float_t origin[3]; | |
252 | Float_t p[3], p0; | |
253 | Float_t tz, txy; | |
254 | Float_t mass; | |
255 | // | |
256 | Int_t nt; | |
257 | static Bool_t first = kTRUE; | |
258 | static Int_t oldID = -1; | |
259 | // | |
260 | ||
261 | if (first && (fNskip == 0)) ReadNextParticle(); | |
262 | first = kFALSE; | |
263 | oldID = fLossID; | |
264 | ||
265 | while(1) { | |
266 | // Push particle to stack | |
267 | mass = TDatabasePDG::Instance()->GetParticle(fPdg)->Mass(); | |
268 | p0 = TMath::Sqrt(fEkin * fEkin + 2. * mass * fEkin); | |
269 | txy = TMath::Sqrt(fDX * fDX + fDY * fDY); | |
270 | if (txy > 1.) { | |
271 | tz = 0.; | |
272 | } else { | |
273 | tz = - TMath::Sqrt(1. - txy); | |
274 | } | |
275 | ||
276 | p[0] = p0 * fDX; | |
277 | p[1] = p0 * fDY; | |
278 | p[2] = p0 * tz; | |
279 | ||
280 | origin[0] = fXS; | |
281 | origin[1] = fYS; | |
282 | origin[2] = 1950.; | |
283 | ||
284 | PushTrack(fTrackIt , -1, fPdg , p, origin, polar, fTS - 1950./2.9979e10, kPNoProcess, nt, fWS); | |
285 | ||
286 | Int_t nc = ReadNextParticle(); | |
287 | ||
288 | if (fLossID != oldID || nc == 0) { | |
289 | oldID = fLossID; | |
290 | break; | |
291 | } | |
292 | } | |
293 | SetHighWaterMark(nt); | |
294 | } | |
295 | ||
296 | ||
297 | Float_t AliGenHalo::GasPressureWeight(Float_t zPrimary) | |
298 | { | |
299 | // | |
300 | // Return z-dependent gasspressure weight = interaction rate [1/m/s]. | |
301 | // | |
302 | Float_t weight = 0.; | |
303 | zPrimary /= 100.; // m | |
304 | if (fRunPeriod < 5) { | |
305 | Float_t zAbs = TMath::Abs(zPrimary); | |
306 | if (zPrimary > 0.) | |
307 | { | |
308 | if (zAbs > fZ1[20]) { | |
309 | weight = 2.e4; | |
310 | } else { | |
311 | for (Int_t i = 1; i < 21; i++) { | |
312 | if (zAbs < fZ1[i]) { | |
313 | weight = fG1[i]; | |
314 | break; | |
315 | } | |
316 | } | |
317 | } | |
318 | } else { | |
319 | if (zAbs > fZ2[20]) { | |
320 | weight = 2.e4; | |
321 | } else { | |
322 | for (Int_t i = 1; i < 21; i++) { | |
323 | if (zAbs < fZ2[i]) { | |
324 | weight = fG2[i]; | |
325 | break; | |
326 | } | |
327 | } | |
328 | } | |
329 | } | |
330 | } else { | |
331 | Int_t index = TMath::BinarySearch(fGPASize, fZ1, zPrimary); | |
332 | weight = fG1[index]; | |
333 | } | |
334 | return weight; | |
335 | } | |
336 | ||
337 | void AliGenHalo::Draw(Option_t *) | |
338 | { | |
339 | // Draws the gas pressure distribution | |
340 | Float_t z[400]; | |
341 | Float_t p[400]; | |
342 | ||
343 | for (Int_t i = 0; i < 400; i++) | |
344 | { | |
345 | z[i] = -20000. + Float_t(i) * 100; | |
346 | p[i] = GasPressureWeight(z[i]); | |
347 | } | |
348 | ||
349 | TGraph* gr = new TGraph(400, z, p); | |
350 | TCanvas* c1 = new TCanvas("c1","Canvas 1",400,10,600,700); | |
351 | c1->cd(); | |
352 | gr->Draw("AL"); | |
353 | } | |
354 | ||
355 | Int_t AliGenHalo::ReadNextParticle() | |
356 | { | |
357 | // Read the next particle from the file | |
358 | Int_t ncols = fscanf(fFile,"%d %f %f %d %f %d %f %f %f %f %f %f %f %f", | |
359 | &fLossID, &fLossT0, &fLossZ, &fLossA, &fLossW, &fPdg, &fXS, &fYS, &fZS, &fDX, &fDY, &fEkin, &fTS, &fWS); | |
360 | fLossZ /= 10.; | |
361 | fXS /= 10.; | |
362 | fYS /= 10.; | |
363 | fZS /= 10.; | |
364 | fTS *= 1.e-9; | |
365 | return (ncols); | |
366 | } | |
367 | ||
368 | void AliGenHalo::SkipEvents() | |
369 | { | |
370 | // | |
371 | // Skip the first fNskip events | |
372 | Int_t skip = fNskip; | |
373 | Int_t oldID = -1; | |
374 | ||
375 | while (skip >= 0) | |
376 | { | |
377 | ReadNextParticle(); | |
378 | if (oldID != fLossID) { | |
379 | oldID = fLossID; | |
380 | skip--; | |
381 | } | |
382 | } | |
383 | } | |
384 | void AliGenHalo::CountEvents() | |
385 | { | |
386 | Int_t nev = 0; | |
387 | Int_t oldID = -1; | |
388 | Int_t nc = 1; | |
389 | while (nc != -1) | |
390 | { | |
391 | nc = ReadNextParticle(); | |
392 | if (oldID != fLossID) { | |
393 | oldID = fLossID; | |
394 | nev++; | |
395 | printf("Number of events %10d %10d \n", nev, oldID); | |
396 | } | |
397 | } | |
398 | ||
399 | ||
400 | rewind(fFile); | |
401 | } | |
402 | ||
403 |