Overlap with absorber corrected.
[u/mrichter/AliRoot.git] / TPC / AliTPCv2.cxx
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 $Log$
18 Revision 1.33  2001/04/20 08:16:47  kowal2
19 Protection against too small betaGamma. Thanks to Ivana and Yves.
20
21 Revision 1.32  2001/03/13 13:07:34  kowal2
22 Corrected bug in the TPC mother volume geometry.
23 Thanks to A. Morsch
24
25 Revision 1.31  2000/11/30 11:48:50  kowal2
26 TLorentzVector.h adde to satisfy the latest changes by Federico
27
28 Revision 1.30  2000/11/14 10:48:57  kowal2
29 Correct material used for TSA4. Thanks to J. Barbosa.
30
31 Revision 1.29  2000/11/06 17:24:10  kowal2
32 Corrected bug in the outer containment vessel and
33 the outer field cage geometry.
34 Thanks to J. Barbosa.
35
36 Revision 1.28  2000/11/02 16:55:24  kowal2
37 Corrected bug in the inner containment vessel geometry.
38 Thanks to J. Belikov
39
40 Revision 1.27  2000/11/02 07:24:11  kowal2
41 Correction in the TPC geometry.
42 Changes due to the new hit structure.
43
44 Revision 1.26  2000/10/05 16:16:29  kowal2
45 Corrections of the hit recording algorithm.
46
47 Revision 1.25  2000/10/02 21:28:18  fca
48 Removal of useless dependecies via forward declarations
49
50 Revision 1.24  2000/08/28 10:02:30  kowal2
51 Corrected bug in the StepManager
52
53 Revision 1.23  2000/07/10 20:57:39  hristov
54 Update of TPC code and macros by M.Kowalski
55
56 Revision 1.22  2000/06/30 12:07:50  kowal2
57 Updated from the TPC-PreRelease branch
58
59 Revision 1.21.2.4  2000/06/26 07:39:42  kowal2
60 Changes to obey the coding rules
61
62 Revision 1.21.2.3  2000/06/25 08:38:41  kowal2
63 Splitted from AliTPCtracking
64
65 Revision 1.21.2.2  2000/06/16 12:58:13  kowal2
66 Changed parameter settings
67
68 Revision 1.21.2.1  2000/06/09 07:15:07  kowal2
69
70 Defaults loaded automatically (hard-wired)
71 Optional parameters can be set via macro called in the constructor
72
73 Revision 1.21  2000/05/15 10:00:30  kowal2
74 Corrected bug in the TPC geometry, thanks to Ivana Hrivnacova
75
76 Revision 1.20  2000/04/17 09:37:33  kowal2
77 removed obsolete AliTPCDigitsDisplay.C
78
79 Revision 1.19.8.2  2000/04/10 08:31:52  kowal2
80
81 Different geometry for different sectors
82 Updated readout chambers
83 Some modifications to StepManager by J.Belikov
84
85 Revision 1.19.8.1  2000/04/10 07:56:53  kowal2
86 Not used anymore - removed
87
88 Revision 1.19  1999/11/04 17:28:07  fca
89 Correct barrel part of HV Degrader
90
91 Revision 1.18  1999/10/14 16:52:08  fca
92 Only use PDG codes and not GEANT ones
93
94 Revision 1.17  1999/10/08 06:27:23  fca
95 Corrected bug in the HV degrader geometry, thanks to G.Tabary
96
97 Revision 1.16  1999/10/04 13:39:54  fca
98 Correct array index problem
99
100 Revision 1.15  1999/09/29 09:24:34  fca
101 Introduction of the Copyright and cvs Log
102
103 */
104
105 //
106 ///////////////////////////////////////////////////////////////////////////////
107 //                                                                           //
108 //  Time Projection Chamber version 2 -- detailed TPC and slow simulation    //
109 //                                                                           //
110 //Begin_Html
111 /*
112 <img src="picts/AliTPCv2Class.gif">
113 */
114 //End_Html
115 //                                                                           //
116 //                                                                           //
117 ///////////////////////////////////////////////////////////////////////////////
118 #include <stdlib.h>
119
120 #include <TMath.h>
121
122 #include "AliTPCv2.h"
123 #include "AliTPCDigitsArray.h"
124 #include "AliRun.h"
125 #include "AliMC.h"
126 #include "AliConst.h"
127 #include "AliPDG.h"
128 #include "AliTPCParam.h"
129 #include "AliTPCParamSR.h"
130 #include "AliTPCTrackHits.h"
131 #include "TLorentzVector.h"
132
133
134 ClassImp(AliTPCv2)
135  
136 //_____________________________________________________________________________
137 AliTPCv2::AliTPCv2(const char *name, const char *title) :
138   AliTPC(name, title) 
139 {
140   //
141   // Standard constructor for Time Projection Chamber version 2
142   //
143   fIdSens=0;
144   fIdLSec=0;
145   fIdUSec=0;
146
147   SetBufferSize(128000);
148
149   SetGasMixt(2,20,10,-1,0.9,0.1,0.); // Ne-CO2 90-10
150
151   // Default sectors
152
153   SetSecAL(4);
154   SetSecAU(4);
155   SetSecLows(1,  2,  3, 19, 20, 21);
156   SetSecUps(37, 38, 39, 37+18, 38+18, 39+18, -1, -1, -1, -1, -1, -1);
157   SetSens(1); // sensitive strips set 
158
159   if (fTPCParam)
160      fTPCParam->Write(fTPCParam->GetTitle());
161 }
162  
163 //_____________________________________________________________________________
164 void AliTPCv2::CreateGeometry()
165 {
166   //
167   // Create the geometry of Time Projection Chamber version 2
168   //
169   //Begin_Html
170   /*
171     <img src="picts/AliTPC.gif">
172   */
173   //End_Html
174   //Begin_Html
175   /*
176     <img src="picts/AliTPCv2Tree.gif">
177   */
178   //End_Html
179
180
181   Int_t *idtmed = fIdtmed->GetArray();
182
183   Float_t dm[50];
184   Int_t idrotm[120];
185
186   Int_t nRotMat = 0;
187
188   Int_t i,ifl1=0;
189
190   // number of sectors
191
192   Int_t nInnerSector = fTPCParam->GetNInnerSector()/2;
193   Int_t nOuterSector = fTPCParam->GetNOuterSector()/2;
194   
195   // --------------------------------------------------- 
196   //        sector specification check 
197   // --------------------------------------------------- 
198   if (fSecAL >= 0) {
199     ifl1 = 0;
200     
201     for (i = 0; i < 6; ++i) {
202       if (fSecLows[i] >= 0 && fSecLows[i] < 2*nInnerSector) {
203         ifl1 = 1;
204         printf("*** SECTOR %d selected\n",fSecLows[i]);
205       }
206     }
207
208   } else {
209     printf("*** ALL LOWER SECTORS SELECTED ***\n");
210     ifl1 = 1;
211   }
212
213   if (ifl1 == 0) {
214     printf("*** ERROR: AT LEAST ONE LOWER SECTOR MUST BE SPECIFIED ***\n");
215     printf("!!! PROGRAM STOPPED !!!\n");
216     exit(1);
217   }
218
219   if (fSecAU >= 0) {
220     
221     for (i = 0; i < 12; ++i) {
222       if (fSecUps[i] > 2*nInnerSector-1 && 
223           fSecUps[i] < 2*(nInnerSector+nOuterSector)) {
224         printf("*** SECTOR %d selected\n",fSecUps[i]);
225       }
226     }
227     
228   } else {
229     printf("*** ALL UPPER SECTORS SELECTED ***\n");
230   }
231   
232  
233
234   //--------------------------------------------------------------------
235
236   //
237   //  Mother volume (Air) - all volumes will be positioned in it
238   //
239   
240   dm[0]=0.;
241   dm[1]=360.;
242   dm[2]=12.;
243
244   //
245  
246   dm[3]= -283.7;
247   dm[4]= 66.2;
248   dm[5]= 277.95;
249
250   //
251
252   dm[6]= -255.6;
253   dm[7]= 66.2;
254   dm[8]= 277.95;
255
256   //
257
258   dm[9]= -73.3;
259   dm[10]= 59.0;
260   dm[11]= 277.95;
261
262   //
263
264   dm[12]= -73.3;
265   dm[13]= 56.9;
266   dm[14]= 277.95;
267
268   //
269
270   dm[15]= -72.1;
271   dm[16]= 56.9;
272   dm[17]= 277.95;
273
274   //
275
276   dm[18]= -72.1;
277   dm[19]= 60.65;
278   dm[20]= 277.95;
279
280   //
281
282   dm[21]= 72.1;
283   dm[22]= 60.65;
284   dm[23]= 277.95;  
285
286   //
287
288   dm[24]= 72.1;
289   dm[25]= 56.9;
290   dm[26]= 277.95;
291
292   //
293
294   dm[27]= 73.3;
295   dm[28]= 56.9;
296   dm[29]= 277.95;
297
298   //
299
300   dm[30]= 73.3;
301   dm[31]= 59.;
302   dm[32]= 277.95;
303
304   //
305
306   dm[33]= 250.4;
307   dm[34]= 66.0;
308   dm[35]= 277.95;
309
310   //
311
312   dm[36]= 283.7;
313   dm[37]= 66.0;
314   dm[38]= 277.95;
315
316
317   gMC->Gsvolu("TPC ","PCON",idtmed[0],dm,39);
318
319
320   //-------------------------------------------------------------------
321   //  Tpc Outer INsulator (CO2)
322   //-------------------------------------------------------------------
323
324   dm[0]= 0.;
325   dm[1]= 360.;
326   dm[2]= 6.;
327
328   //
329  
330   dm[3]= -253.6;
331   dm[4]= 258.;
332   dm[5]= 266.65;
333
334   //
335
336   dm[6]= -253.;
337   dm[7]= 258.;
338   dm[8]= 266.65;
339
340   dm[9]= -253.;
341   dm[10]= 258.;
342   dm[11]= 277.97;
343
344   dm[12]= 253.6;
345   dm[13]= 258.;
346   dm[14]= 277.97;
347
348   //
349
350   dm[15]= 253.6;
351   dm[16]= 265.2;
352   dm[17]= 277.95;
353
354   //
355
356   dm[18]= 255.6;
357   dm[19]= 265.2;
358   dm[20]= 277.95;
359
360
361   gMC->Gsvolu("TOIN","PCON",idtmed[3],dm,21);
362
363   //---------------------------------------------------------------
364   // shreds (G10) - TPC Rings
365   //---------------------------------------------------------------
366
367   gMC->Gsvolu("TPCR","TUBE",idtmed[12],dm,0);
368
369   dm[0]= 258.;
370   dm[1]= 266.65;
371   dm[2]= 0.3;
372
373   gMC->Gsposp("TPCR",1,"TOIN",0.,0.,-253.3,0,"ONLY",dm,3); // left bottom
374
375   //
376
377   dm[0]= 258.;
378   dm[1]= 270.9;
379   dm[2]= 0.3;
380
381   gMC->Gsposp("TPCR",2,"TOIN",0.,0.,253.3,0,"ONLY",dm,3); // right
382
383   //
384
385   dm[0]= 272.2;
386   dm[1]= 277.95;
387   dm[2]= 0.3;
388
389   gMC->Gsposp("TPCR",3,"TOIN",0.,0.,-250.7,0,"ONLY",dm,3); // left top
390
391   //----------------------------------------------------------------
392   // Tpc Outer Contaiment Vessel  
393   //  mother volume - Al, daughters - composite (sandwich)
394   //----------------------------------------------------------------
395   
396   dm[0]= 0.;
397   dm[1]= 360.;
398   dm[2]=6.;
399
400   //
401
402   dm[3]= -250.4;
403   dm[4]= 272.2;
404   dm[5]= 277.95;
405
406   //
407
408   dm[6]= -248.4;
409   dm[7]= 272.2;
410   dm[8]= 277.95;
411
412   //
413   dm[9]= -248.4;
414   dm[10]= 274.81;
415   dm[11]= 277.95;
416   //
417
418   dm[12]= 253.6;
419   dm[13]= 274.81;
420   dm[14]= 277.95;
421
422   //
423
424   dm[15]= 253.6;
425   dm[16]= 265.2;
426   dm[17]= 277.95;
427
428   // 
429
430   dm[18]= 255.6;
431   dm[19]= 265.2;
432   dm[20]= 277.95;
433
434   gMC->Gsvolu("TOCV","PCON",idtmed[4],dm,21);
435
436   // Daughter volumes
437
438   // Tpc SAndwich 1 - Al
439  
440   dm[0]= 274.81;
441   dm[1]= 277.95;
442   dm[2]= 251.7;
443
444   gMC->Gsvolu("TSA1","TUBE",idtmed[4],dm,3);
445
446   // Tpc SAndwich 2 - Tedlar
447
448   dm[0] += 5.e-3;
449   dm[1] -= 5.e-3;
450   
451   gMC->Gsvolu("TSA2","TUBE",idtmed[9],dm,3);
452
453   // Tpc SAndwich 3 - Kevlar
454
455   dm[0] += 5e-3;
456   dm[1] -= 5.e-3;
457
458   gMC->Gsvolu("TSA3","TUBE",idtmed[5],dm,3);
459
460   // Tpc SAndwich 4 - NOMEX honeycomb
461
462   dm[0] += 0.06;
463   dm[1] -= 0.06;
464
465   gMC->Gsvolu("TSA4","TUBE",idtmed[6],dm,3);  
466   
467   // 4->3->2->1->TOCV
468
469   gMC->Gspos("TSA4",1,"TSA3",0.,0.,0.,0,"ONLY");
470   gMC->Gspos("TSA3",1,"TSA2",0.,0.,0.,0,"ONLY");
471   gMC->Gspos("TSA2",1,"TSA1",0.,0.,0.,0,"ONLY");
472
473   gMC->Gspos("TSA1",1,"TOCV",0.,0.,2.6,0,"ONLY");
474
475   // TCOV-> TOIN
476
477   gMC->Gspos("TOCV",1,"TOIN",0.,0.,0.,0,"ONLY");
478
479   //-------------------------------------------------------
480   //  Tpc Outer Field Cage
481   //  mother volume - Al, daughters - composite (sandwich)
482   //-------------------------------------------------------
483
484   dm[0]=0.;
485   dm[1]=360.;
486   dm[2]=6.;
487
488   dm[3]= -253.;
489   dm[4]= 258.;
490   dm[5]= 277.95;
491
492   //
493
494   dm[6]= -251.;
495   dm[7]= 258.;
496   dm[8]= 277.95;
497
498   //
499  
500   dm[9]= -251.;
501   dm[10]= 258.;
502   dm[11]= 260.05;
503
504   //
505
506   dm[12]= 251.;
507   dm[13]= 258.;
508   dm[14]= 260.05;
509
510   //
511
512   dm[15]= 251.;
513   dm[16]= 258.;
514   dm[17]= 270.9;
515
516   //
517
518   dm[18]= 253.;
519   dm[19]= 258.;
520   dm[20]= 270.9;
521
522   gMC->Gsvolu("TOFC","PCON",idtmed[4],dm,21);  
523
524   // Daughter volumes 
525
526   // Tpc SAndwich 5 - Tedlar
527
528   dm[0]= 258.;
529   dm[1]= 260.05;
530   dm[2]= 251.7;
531
532   gMC->Gsvolu("TSA5","TUBE",idtmed[9],dm,3);
533
534   // Tpc SAndwich 6 - Kevlar
535
536   dm[0] += 5.e-3;
537   dm[1] -= 5.e-3;
538
539   gMC->Gsvolu("TSA6","TUBE",idtmed[5],dm,3);
540
541
542   // Tpc SAndwich 8 - NOMEX
543
544   dm[0] += 0.02;
545   dm[1] -= 0.02;
546
547   gMC->Gsvolu("TSA7","TUBE",idtmed[6],dm,3);    
548
549   // 7->6->5->TOFC
550
551   gMC->Gspos("TSA7",1,"TSA6",0.,0.,0.,0,"ONLY");
552   gMC->Gspos("TSA6",1,"TSA5",0.,0.,0.,0,"ONLY"); 
553
554   gMC->Gspos("TSA5",1,"TOFC",0.,0.,0.,0,"ONLY");
555
556   // TOFC->TOIN
557
558   gMC->Gspos("TOFC",1,"TOIN",0.,0.,0.,0,"ONLY"); 
559
560   // TOIN->TPC
561
562   gMC->Gspos("TOIN",1,"TPC ",0.,0.,0.,0,"ONLY");
563
564   //--------------------------------------------------------------------
565   // Tpc Inner INsulator (CO2)
566   //--------------------------------------------------------------------
567
568
569   dm[0]=0.;
570   dm[1]= 360.;
571   dm[2]= 15.;
572
573   //
574
575   dm[3]= -255.6;
576   dm[4]= 66.2;
577   dm[5]= 74.8;
578
579   //
580
581   Float_t tanL = (66.2-59.0)/(255.6-73.3); // tangent of the left cone part
582
583   dm[6]= -253.6;
584   dm[7]= 59.0+ (253.6-73.3)*tanL;
585   dm[8]= 74.8;
586
587   //
588
589   dm[9]= -253.6;
590   dm[10]= dm[7];
591   dm[11]= 79.2;
592
593   //
594
595   dm[12]= -73.3;
596   dm[13]= 59.0;
597   dm[14]= 79.2;
598
599   //
600
601   dm[15]= -73.3;
602   dm[16]= 56.9;
603   dm[17]= 79.2;
604
605   //
606
607   dm[18]= -72.1;
608   dm[19]= 59.6;
609   dm[20]= 79.2;
610
611   //
612
613   dm[21]= -72.1;
614   dm[22]= 60.65;
615   dm[23]= 79.2;
616
617   //
618
619   dm[24]= 72.1;
620   dm[25]= 60.65;
621   dm[26]= 79.2;  
622
623   //
624
625   dm[27]= 72.1;
626   dm[28]= 59.6;
627   dm[29]= 79.2;
628
629   //
630
631   dm[30]= 73.3;
632   dm[31]= 56.9;
633   dm[32]= 79.2;
634
635   //
636
637   dm[33]= 73.3;
638   dm[34]= 59.0;
639   dm[35]= 79.2;
640
641   //
642
643   dm[36]= 250.4;
644   dm[37]= 66.0;
645   dm[38]= 79.2;
646
647   //
648   
649   dm[39]= 253.0;
650   dm[40]= 66.0;
651   dm[41]= 79.2;
652
653   //
654
655   dm[42]= 253.0;
656   dm[43]= 75.3;
657   dm[44]= 79.2;
658
659   //
660
661   dm[45]= 253.6;
662   dm[46]= 75.3;
663   dm[47]= 79.2;
664
665   gMC->Gsvolu("TIIN","PCON",idtmed[3],dm,48);
666
667
668   //--------------------------------------------------------------------
669   //  Tpc Inner Containment vessel, Left part
670   //  mother volume - Al, daughter - composite (sandwich)
671   //--------------------------------------------------------------------
672
673   dm[0]= 0.;
674   dm[1]= 360.;
675   dm[2]= 8.;
676
677   //
678
679   dm[3]= -255.6;
680   dm[4]= 66.2;
681   dm[5]= 74.8;
682
683   //
684
685   Float_t cosL = 1./TMath::Sqrt(1.+tanL*tanL);
686   Float_t sandThick = 2.14; // cone composite thickness
687
688
689   //
690
691   dm[6]= -253.6;
692   dm[7]= 59.0 + (253.6-73.3)*tanL;
693   dm[8]= 74.8;
694
695   //
696
697   dm[9]= -253.6;
698   dm[10]= dm[7];
699   dm[11]= dm[7]+sandThick/cosL;
700
701   //
702
703   dm[12]= -75.6;
704   dm[13]= 59.0+(75.6-73.3)*tanL;
705   dm[14]= dm[13]+sandThick/cosL;
706
707   //
708
709   dm[15]= -75.6;
710   dm[16]= dm[13];
711   dm[17]= 60.65;
712
713   //
714
715   dm[18]= -73.3;
716   dm[19]= 59.0;
717   dm[20]= 60.65;
718
719   //
720
721   dm[21]= -73.3;
722   dm[22]= 56.9;
723   dm[23]= 60.65;
724
725   //
726
727   dm[24]= -72.1;
728   dm[25]= 56.9;
729   dm[26]= 60.65;
730
731   gMC->Gsvolu("TICL","PCON",idtmed[4],dm,27);
732
733   // Daughter volumes 
734
735   // Tpc SAndwich 9 - Al
736
737   dm[0]= 0.;
738   dm[1]= 360.;
739   dm[2]= 2.;
740
741   //
742
743   dm[3]= - 254.3;
744   dm[4]= 59.0+(254.3-73.3)*tanL;
745   dm[5]= dm[4]+sandThick/cosL;
746
747   //
748
749   dm[6]= -78.3;
750   dm[7]= 59.0+(78.3-73.3)*tanL;
751   dm[8]= dm[7]+sandThick/cosL;
752
753   //
754
755   gMC->Gsvolu("TSA9","PCON",idtmed[4],dm,9);
756
757   // Tpc SAndwich 10 - Tedlar
758
759   dm[4]+= 5.e-3/cosL;
760   dm[5]-= 5.e-3/cosL;
761
762   //
763
764   dm[7]+= 5.e-3/cosL;
765   dm[8]+= 5.e-3/cosL;
766
767   gMC->Gsvolu("TS10","PCON",idtmed[9],dm,9); 
768
769   // Tpc SAndwich 11 - Kevlar
770
771   dm[4]+= 5.e-3/cosL;
772   dm[5]-= 5.e-3/cosL;
773
774   //
775
776   dm[7]+= 5.e-3/cosL;
777   dm[8]+= 5.e-3/cosL;
778
779   gMC->Gsvolu("TS11","PCON",idtmed[5],dm,9); 
780
781   // Tpc SAndwich 12 - NOMEX
782
783   dm[4]+= 0.06/cosL;
784   dm[5]-= 0.06/cosL;
785
786   //
787
788   dm[7]+= 0.06/cosL;
789   dm[8]+= 0.06/cosL;
790
791   gMC->Gsvolu("TS12","PCON",idtmed[6],dm,9);   
792
793   // 12->11->10->9
794
795   gMC->Gspos("TS12",1,"TS11",0.,0.,0.,0,"ONLY");
796   gMC->Gspos("TS11",1,"TS10",0.,0.,0.,0,"ONLY");
797   gMC->Gspos("TS10",1,"TSA9",0.,0.,0.,0,"ONLY");
798
799   // TSA9->TICL
800
801   gMC->Gspos("TSA9",1,"TICL",0.,0.,0.,0,"ONLY");
802  
803   //--------------------------------------------------------------------
804   //  Tpc Inner Containment vessel, Right part
805   //  mother volume - Al, daughter - composite (sandwich)
806   //--------------------------------------------------------------------
807
808   dm[0]= 0.;
809   dm[1]= 360.;
810   dm[2]=8.;
811
812   //
813
814   dm[3]= 72.1;
815   dm[4]= 56.9;
816   dm[5]= 60.65;
817
818   //
819
820   dm[6]= 73.3;
821   dm[7]= 56.9;
822   dm[8]= 60.65;
823
824   //
825
826   dm[9]= 73.3;
827   dm[10]= 59.0;
828   dm[11]= 60.65;
829
830   //
831
832   Float_t tanR = (66.0-59.0)/(250.5-73.3); // to avoid accuracy problems
833   Float_t cosR = 1./TMath::Sqrt(1.+tanR*tanR); //as above
834
835   //
836
837   dm[12]= 75.6;
838   dm[13]= 59.0+(75.6-73.3)*tanR;
839   dm[14]= 60.65;
840
841   //
842
843   dm[15]= 75.6;
844   dm[16]= dm[13];
845   dm[17]= dm[16]+sandThick/cosR;
846
847   //
848
849   dm[18]= 248.4;
850   dm[19]= 59.0+(248.4-73.3)*tanR;
851   dm[20]= dm[19]+sandThick/cosR;
852
853   //
854
855   dm[21]= 248.4;
856   dm[22]= dm[19];
857   dm[23]= 70.2;
858
859   //
860
861   dm[24]= 250.4;
862   dm[25]= 66.0;
863   dm[26]= 70.2;
864
865   gMC->Gsvolu("TICR","PCON",idtmed[4],dm,27);
866
867
868
869   // Daughter volumes 
870
871   // Tpc SAndwich 13 - Al
872
873   dm[0]= 0.;
874   dm[1]= 360.;
875   dm[2]= 2.;
876
877   //
878
879   dm[3]= 78.3;
880   dm[4]= 59.0+(78.3-73.3)*tanR;
881   dm[5]= dm[4]+sandThick/cosR;
882
883   //
884
885   dm[6]= 249.1;
886   dm[7]= 59.0+(249.1-73.3)*tanR;
887   dm[8]= dm[7]+sandThick/cosR;
888
889   //
890
891   gMC->Gsvolu("TS13","PCON",idtmed[4],dm,9);
892
893   // Tpc SAndwich 14 - Tedlar
894
895   dm[4]+= 5.e-3/cosR;
896   dm[5]-= 5.e-3/cosR;
897
898   //
899
900   dm[7]+= 5.e-3/cosR;
901   dm[8]+= 5.e-3/cosR;
902
903   gMC->Gsvolu("TS14","PCON",idtmed[9],dm,9); 
904
905   // Tpc SAndwich 15 - Kevlar
906
907   dm[4]+= 5.e-3/cosR;
908   dm[5]-= 5.e-3/cosR;
909
910   //
911
912   dm[7]+= 5.e-3/cosR;
913   dm[8]+= 5.e-3/cosR;
914
915   gMC->Gsvolu("TS15","PCON",idtmed[5],dm,9); 
916
917   // Tpc SAndwich 16 - NOMEX
918
919   dm[4]+= 0.06/cosR;
920   dm[5]-= 0.06/cosR;
921
922   //
923
924   dm[7]+= 0.06/cosR;
925   dm[8]+= 0.06/cosR;
926
927   gMC->Gsvolu("TS16","PCON",idtmed[6],dm,9);   
928
929   // 16->15->14->13
930
931   gMC->Gspos("TS16",1,"TS15",0.,0.,0.,0,"ONLY");
932   gMC->Gspos("TS15",1,"TS14",0.,0.,0.,0,"ONLY");
933   gMC->Gspos("TS14",1,"TS13",0.,0.,0.,0,"ONLY");
934
935   // TS12->TICR
936
937   gMC->Gspos("TS13",1,"TICR",0.,0.,0.,0,"ONLY");
938
939   //------------------------------------------------------
940   // Tpc Inner Field Cage
941   // mother volume - Al, daughters - composite (sandwich)
942   //------------------------------------------------------
943
944   dm[0]= 0.;
945   dm[1]= 360.;
946   dm[2]=6.;
947
948   //
949
950   dm[3]= -253.0;
951   dm[4]= 70.7;
952   dm[5]= 79.2;
953
954   //
955
956   dm[6]= -251.0;
957   dm[7]= 70.7;
958   dm[8]= 79.2;
959
960   //
961
962   dm[9]= -251.0;
963   dm[10]= 77.15;
964   dm[11]= 79.2;
965
966   //
967   
968   dm[12]= 251.0;
969   dm[13]= 77.15;
970   dm[14]= 79.2;
971
972   //
973
974   dm[15]= 251.0;
975   dm[16]= 66.0;
976   dm[17]= 79.2;
977
978   //
979
980   dm[18]= 253.0;
981   dm[19]= 66.0;
982   dm[20]= 79.2;
983
984   gMC->Gsvolu("TIFC","PCON",idtmed[4],dm,21);
985
986   // Daughter volumes
987
988   // Tpc Sandwich 17 - Tedlar
989
990   dm[0]= 77.15;
991   dm[1]= 79.2;
992   dm[2]= 251.7;
993
994   gMC->Gsvolu("TS17","TUBE",idtmed[9],dm,3);
995
996   // Tpc Sandwich 18 - Kevlar
997
998   dm[0]+= 5.e-3;
999   dm[1]-= 5.e-3;
1000
1001   gMC->Gsvolu("TS18","TUBE",idtmed[5],dm,3);
1002
1003
1004   // Tpc Sandwich 19 - NOMEX
1005
1006   dm[0]+= 0.02;
1007   dm[1]-= 0.02;
1008
1009   gMC->Gsvolu("TS19","TUBE",idtmed[6],dm,3);
1010
1011   // 19->18->17
1012
1013   gMC->Gspos("TS19",1,"TS18",0.,0.,0.,0,"ONLY");
1014   gMC->Gspos("TS18",1,"TS17",0.,0.,0.,0,"ONLY");
1015
1016   // TS17->TIFC
1017
1018   gMC->Gspos("TS17",1,"TIFC",0.,0.,0.,0,"ONLY");
1019
1020   // TPC Rings
1021
1022   dm[0]= 70.7;
1023   dm[1]= 79.2;
1024   dm[2]= 0.3;
1025
1026   gMC->Gsposp("TPCR",4,"TIIN",0.,0.,-253.3,0,"ONLY",dm,3);
1027
1028   dm[0]= 66.0;
1029   dm[1]= 70.2;  
1030
1031   gMC->Gsposp("TPCR",5,"TIIN",0.,0.,250.7,0,"ONLY",dm,3);
1032
1033   dm[0]= 75.3;
1034   dm[1]= 79.2;  
1035
1036   gMC->Gsposp("TPCR",6,"TIIN",0.,0.,253.3,0,"ONLY",dm,3);  
1037
1038   // TICL->TIIN
1039
1040   gMC->Gspos("TICL",1,"TIIN",0.,0.,0.,0,"ONLY");
1041
1042   // TICR->TIIN
1043
1044   gMC->Gspos("TICR",1,"TIIN",0.,0.,0.,0,"ONLY");
1045
1046   // TIFC->TIIN
1047
1048   gMC->Gspos("TIFC",1,"TIIN",0.,0.,0.,0,"ONLY");
1049
1050   // Tpc Sandwich 21 - Al (central barrel)
1051
1052   dm[0]= 60.65;
1053   dm[1]= 61.21;
1054   dm[2]= 75.2;
1055
1056   gMC->Gsvolu("TS21","TUBE",idtmed[4],dm,3);
1057
1058   // Tpc Sandwich 22 - Tedlar (central barrel) 
1059
1060   dm[0]+= 5.e-3;
1061   dm[1]-= 5.e-3;
1062
1063   gMC->Gsvolu("TS22","TUBE",idtmed[9],dm,3); 
1064
1065   // Tpc Sandwich 23 - Kevlar (central barrel) 
1066
1067   dm[0]+= 5.e-3;
1068   dm[1]-= 5.e-3;
1069
1070   gMC->Gsvolu("TS23","TUBE",idtmed[5],dm,3); 
1071
1072   // Tpc Sandwich 24 - NOMEX (central barrel) 
1073
1074   dm[0]+= 0.02;
1075   dm[1]-= 0.02;
1076
1077   gMC->Gsvolu("TS24","TUBE",idtmed[6],dm,3); 
1078
1079   // 24->23->22->21
1080
1081   gMC->Gspos("TS24",1,"TS23",0.,0.,0.,0,"ONLY");
1082   gMC->Gspos("TS23",1,"TS22",0.,0.,0.,0,"ONLY");
1083   gMC->Gspos("TS22",1,"TS21",0.,0.,0.,0,"ONLY");
1084
1085   gMC->Gspos("TS21",1,"TIIN",0.,0.,0.,0,"ONLY");
1086
1087   // put everything into the TPC 
1088
1089   gMC->Gspos("TIIN",1,"TPC ",0.,0.,0.,0,"ONLY");
1090
1091
1092   //---------------------------------------------------------
1093   //  Tpc Dift Gas volume Nonsensitive (Ne-CO2 90/10)
1094   //  and its daughters (HV membrane, rods, readout chambers)
1095   //---------------------------------------------------------
1096
1097   dm[0]= 79.2;
1098   dm[1]= 258.0;
1099   dm[2]= 253.6;
1100
1101   gMC->Gsvolu("TDGN","TUBE",idtmed[1],dm,3);  // nonsensitive 
1102
1103     // sector opening angles
1104
1105   Float_t innerOpenAngle = fTPCParam->GetInnerAngle();
1106   Float_t outerOpenAngle = fTPCParam->GetOuterAngle();
1107
1108   // sector angle shift
1109
1110   Float_t innerAngleShift = fTPCParam->GetInnerAngleShift();
1111
1112   // All above parameters are identical for inner and outer
1113   // sectors. The distinction is kept for the historical reasons
1114   // and eventually will disappear.
1115
1116   Float_t tanAlpha = TMath::Tan(0.5*innerOpenAngle);
1117   Float_t cosAlpha = TMath::Sqrt(1.+tanAlpha*tanAlpha);
1118   Float_t space;
1119
1120   //-------------------------------------------------------------------------
1121   //   Tpc Inner Readout Chambers 
1122   //-------------------------------------------------------------------------
1123
1124   dm[0]= 14.483;
1125   dm[1]= 23.3345; 
1126   dm[2]= 1.6; // thickness
1127   dm[3]= 25.1;
1128
1129   gMC->Gsvolu("TIRC","TRD1",idtmed[4],dm,4);
1130
1131   // this volume will be positioned in the empty space
1132   // of the end-cap to avoid overlaps
1133
1134   dm[0]= 13.7305;
1135   dm[1]= 21.1895;
1136   dm[2]= 2.25;
1137   dm[3]= 21.15;
1138
1139   gMC->Gsvolu("TIC1","TRD1",idtmed[4],dm,4);
1140
1141   //------------------------------------------------
1142   // Tpc Inner readout chamber Pad Plane
1143   //------------------------------------------------
1144
1145   dm[0]= 14.483;
1146   dm[1]= 23.3345;
1147   dm[2]= 0.5;
1148   dm[3]= 25.1;
1149
1150   gMC->Gsvolu("TIPP","TRD1",idtmed[12],dm,4);
1151
1152   // 
1153
1154   dm[0] -= 1.218511934;
1155   dm[1] -= 1.218511934;
1156   dm[2] = 0.35;
1157
1158   gMC->Gsvolu("TIC3","TRD1",idtmed[1],dm,4);
1159
1160   gMC->Gspos("TIC3",1,"TIPP",0.,0.15,0.,0,"ONLY");
1161
1162   gMC->Gspos("TIPP",1,"TIRC",0.,1.1,0.,0,"ONLY");
1163
1164   //----------------------------------------------
1165   // Tpc Readout Chambers Empty spaces - for both
1166   // inner and outer sectors
1167   //----------------------------------------------
1168
1169   gMC->Gsvolu("TRCE","TRD1",idtmed[0],dm,0);
1170
1171   // Inner sector - 4 spaces
1172
1173
1174   dm[3] = 4.7625;
1175   dm[0] = 12.472;
1176
1177   Float_t rr = 90.52;
1178   Float_t zz;
1179
1180   zz= -12.7875;
1181   
1182   space = rr*tanAlpha-dm[0];
1183
1184   for(Int_t nsLow=0;nsLow<4;nsLow++){
1185
1186     rr += 9.525;
1187     dm[1]= rr*tanAlpha - space;  
1188
1189     dm[2]=0.8;
1190
1191     gMC->Gsposp("TRCE",nsLow+1,"TIRC",0.,-0.8,zz,0,"ONLY",dm,4);
1192
1193     //
1194
1195     dm[2]= 1.2;
1196
1197     gMC->Gsposp("TRCE",nsLow+5,"TIC1",0.,1.05,zz-2.1,0,"ONLY",dm,4);
1198
1199     rr += 0.4;
1200     dm[0] = rr*tanAlpha - space;
1201     zz += (0.4+9.525); 
1202
1203   }
1204
1205   dm[0]= 12.472;
1206   // dm[1] - this is the dm[1] from the previous TRCE
1207   dm[2]= 1.05;
1208   dm[3]= 19.65;
1209
1210   gMC->Gsposp("TRCE",9,"TIC1",0.,-1.2,0.,0,"ONLY",dm,4); 
1211
1212   //
1213   // TPc Space for Connectors
1214   //
1215
1216   dm[0]= .3;
1217   dm[1]= .3;
1218   dm[2]= 4.5;
1219
1220   gMC->Gsvolu("TPSC","BOX ",idtmed[0],dm,3);
1221
1222   // TPC Connectors
1223
1224   dm[0]= .25;
1225   dm[1]= .15;
1226   dm[2]= 3.75;
1227
1228   gMC->Gsvolu("TPCC","BOX ",idtmed[13],dm,3); 
1229
1230   gMC->Gspos("TPCC",1,"TPSC",0.,0.15,0.,0,"ONLY");
1231
1232   zz = -12.7875;
1233
1234   Float_t alpha;
1235   Float_t astep;
1236
1237   Float_t phi1,phi2,phi3,theta1,theta2,theta3; // rotation angles
1238
1239   // inner part of the inner sector - 2 x 20 holes
1240   
1241   astep = 20.00096874/19.;
1242
1243   alpha = 10.00048437-astep;
1244
1245   Float_t x1,x2;
1246
1247     x1 = 13.31175725;
1248     x1 -= 0.996357832; 
1249
1250     x2 = 15.06180253;
1251     x2 -= 1.163028812;
1252
1253   Int_t ncon;
1254
1255   for(ncon=0;ncon<20;ncon++){
1256
1257     phi1 = 0.;
1258     theta1 = 90.+alpha;
1259     phi2=90.;
1260     theta2 = 90.;
1261     phi3 = (alpha>0) ? 0. : 180.;
1262     theta3 = TMath::Abs(alpha);
1263
1264     AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
1265
1266  
1267
1268     gMC->Gspos("TPSC",ncon+1,"TIRC",x1,0.3,-12.7875,idrotm[nRotMat],"ONLY");
1269     gMC->Gspos("TPSC",ncon+21,"TIRC",x2,0.3,-2.8625,idrotm[nRotMat],"ONLY");
1270
1271
1272     x1 -= 1.296357833;
1273     x2 -= 1.463028812;
1274
1275     alpha -= astep;   
1276     nRotMat++; 
1277
1278   }
1279
1280   // outer part of the inner sector - 2 x 25 holes
1281
1282    astep = 20.00096874/24.; 
1283    alpha = 10.00048437-astep;
1284
1285    x1 = 16.81184781;
1286    x1 -= 1.016295986;
1287
1288    x2 = 18.5618931;
1289    x2 -= 1.150914854;
1290
1291   for(ncon=0;ncon<25;ncon++){
1292
1293     phi1 = 0.;
1294     theta1 = 90.+alpha;
1295     phi2=90.;
1296     theta2 = 90.;
1297     phi3 = (alpha>0) ? 0. : 180.;
1298     theta3 = TMath::Abs(alpha);
1299
1300     AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
1301
1302  
1303
1304     gMC->Gspos("TPSC",ncon+41,"TIRC",x1,0.3,7.0625,idrotm[nRotMat],"ONLY");
1305     gMC->Gspos("TPSC",ncon+66,"TIRC",x2,0.3,16.9875,idrotm[nRotMat],"ONLY");
1306
1307
1308     x1 -= 1.316295986;
1309     x2 -= 1.450914854;
1310
1311     alpha -= astep;   
1312     nRotMat++; 
1313
1314   }  
1315
1316   //--------------------------------------------------------------------------
1317   //  TPC Outer Readout Chambers
1318   //  this is NOT a final design
1319   //--------------------------------------------------------------------------
1320
1321   dm[0]= 23.3875;
1322   dm[1]= 43.524;
1323   dm[2]= 1.5; //thickness
1324   dm[3]= 57.1;
1325
1326   gMC->Gsvolu("TORC","TRD1",idtmed[4],dm,4);
1327
1328   //------------------------------------------------
1329   // Tpc Outer readout chamber Pad Plane
1330   //------------------------------------------------
1331
1332   dm[2]= 0.5;
1333
1334   gMC->Gsvolu("TOPP","TRD1",idtmed[12],dm,4);
1335
1336   dm[0] -= 1.218511934;
1337   dm[1] -= 1.218511934;
1338   dm[2] = 0.35;
1339
1340   gMC->Gsvolu("TOC3","TRD1",idtmed[1],dm,4);
1341
1342   gMC->Gspos("TOC3",1,"TOPP",0.,0.15,0.,0,"ONLY");
1343
1344   gMC->Gspos("TOPP",1,"TORC",0.,1.0,0.,0,"ONLY");
1345
1346   // empty space
1347
1348
1349   dm[0]= 21.035;
1350   dm[1]= 38.7205;
1351   dm[2]= 0.7; 
1352   dm[3]= 50.15;
1353
1354   gMC->Gsposp("TRCE",10,"TORC",0.,-0.8,-2.15,0,"ONLY",dm,4);  
1355
1356   dm[0]= 22.2935;
1357   dm[1]= 40.5085;
1358   dm[2]= 2.25;
1359   dm[3]= 51.65;
1360
1361   gMC->Gsvolu("TOC1","TRD1",idtmed[4],dm,4);
1362
1363   dm[0]= 21.35;
1364   dm[1]= 38.7205;
1365   dm[2]= 2.25;
1366   dm[3]= 50.15;
1367
1368   gMC->Gsposp("TRCE",11,"TOC1",0.,0.,0.,0,"ONLY",dm,4); 
1369
1370
1371
1372   //-----------------------------------------------
1373   // Tpc Services Support Wheel
1374   //-----------------------------------------------
1375
1376   dm[0]=0.;
1377   dm[1]=360.;
1378   dm[2]=18.;
1379   dm[3]=2.;
1380
1381   dm[4]= -5.;
1382   dm[5]= 77.017;
1383   dm[6]= 255.267;
1384
1385   dm[7]= 5.;
1386   dm[8]= dm[5];
1387   dm[9]= dm[6];
1388
1389   gMC->Gsvolu("TSSW","PGON",idtmed[4],dm,10);
1390
1391   // Tpc Services Wheel Cover
1392
1393   dm[4]= -0.5;
1394   dm[7]= 0.5;
1395
1396   gMC->Gsvolu("TSWC","PGON",idtmed[4],dm,10);
1397
1398   // Tpc Service wheel Cover Empty space
1399    
1400   dm[0]= 10.99;
1401   dm[1]= 39.599;
1402   dm[2]= .5;
1403   dm[3]= 81.125;
1404
1405   gMC->Gsvolu("TSCE","TRD1",idtmed[0],dm,4);
1406
1407   // Tpc services Wheel Empty Spaces
1408
1409   dm[0]= 13.18017507;
1410   dm[1]= 44.61045938;
1411   dm[2]= 4.;
1412   dm[3]= 89.125;
1413
1414   gMC->Gsvolu("TWES","TRD1",idtmed[0],dm,4);
1415
1416   // Tpc Services Wheel Bars
1417
1418   gMC->Gsvolu("TSWB","TRD1",idtmed[4],dm,0);
1419
1420   // bars-> TWES
1421
1422   dm[2]= 4.;
1423   dm[3]= .4;
1424
1425   dm[0]= 13.8149522;
1426   dm[1]= 13.95601379;
1427   
1428   gMC->Gsposp("TSWB",1,"TWES",0.,0.,-85.125,0,"ONLY",dm,4);
1429
1430   dm[0]= 43.83462067; 
1431   dm[1]= 43.97568225;
1432
1433   gMC->Gsposp("TSWB",2,"TWES",0.,0.,85.125,0,"ONLY",dm,4);
1434
1435   // TPc ELectronics - right now 30% X0 Si
1436
1437   dm[0]= 14.03813696;
1438   dm[1]= 43.3524075;
1439   dm[2]= 1.404;
1440   dm[3]= 83.125;
1441
1442   gMC->Gsvolu("TPEL","TRD1",idtmed[11],dm,4);
1443   gMC->Gspos("TPEL",1,"TWES",0.,0.,0.,0,"ONLY");
1444
1445   //--------------------------------------------------------------------------
1446   //  End caps
1447   //--------------------------------------------------------------------------
1448
1449   // TPc Main Wheel - Al
1450
1451   dm[0]= 75.3;
1452   dm[1]= 264.8;
1453   dm[2]= 3.0;
1454
1455   gMC->Gsvolu("TPMW","TUBE",idtmed[4],dm,3);
1456
1457   // TPc Extra Wheel (to avoid overlapping) - Al
1458
1459   dm[0]= 264.8;
1460   dm[1]= 277.0;
1461   dm[2]= 1.95;
1462
1463   gMC->Gsvolu("TPEW","TUBE",idtmed[4],dm,3);
1464
1465   //--------------------------------------------------------------------------
1466   //  Tpc Empty Space for the Readout chambers
1467   //--------------------------------------------------------------------------  
1468
1469   Float_t rLow= 86.2;
1470   Float_t rUp= 243.5;
1471   Float_t dR = 0.5*(rUp-rLow);
1472
1473   space= 1.4/cosAlpha; // wheel ribs are 2.8 cm wide
1474
1475   dm[0]= rLow*tanAlpha-space;
1476   dm[1]= rUp*tanAlpha-space;
1477   dm[2]= 3.0;
1478   dm[3]= dR;
1479
1480   gMC->Gsvolu("TESR","TRD1",idtmed[0],dm,4);
1481
1482   // TIC1->TESR
1483
1484
1485   gMC->Gspos("TIC1",1,"TESR",0.,0.75,-dR+23.97,0,"ONLY");
1486
1487
1488   // TOC1->TESR
1489
1490   gMC->Gspos("TOC1",1,"TESR",0.,0.75,dR-55.02,0,"ONLY");
1491
1492   // Tpc Empty Space Bars - Al (daughters of TESR)
1493
1494   Float_t zBar;
1495
1496   gMC->Gsvolu("TESB","TRD1",idtmed[4],dm,0);
1497
1498   // lower bar
1499
1500   dm[0]= rLow*tanAlpha-space;
1501   dm[1]= 88.7*tanAlpha-space;
1502   dm[2]= 0.95;
1503   dm[3]= 1.275;
1504
1505   zBar = -dR+dm[3];
1506
1507   gMC->Gsposp("TESB",1,"TESR",0.,2.05,zBar,0,"ONLY",dm,4);
1508
1509   // middle bar
1510
1511   dm[0]= 131.65*tanAlpha-space;
1512   dm[1]= 136.5*tanAlpha-space;
1513   dm[3]= 2.425;
1514
1515   zBar = -dR +131.65+dm[3]-rLow;
1516
1517   gMC->Gsposp("TESB",2,"TESR",0.,2.05,zBar,0,"ONLY",dm,4);
1518
1519   // upper bar
1520
1521   dm[0]= 240.4*tanAlpha-space;
1522   dm[1]= rUp*tanAlpha-space;
1523   dm[3]= 1.55;
1524
1525   zBar = dR-dm[3];
1526
1527   gMC->Gsposp("TESB",3,"TESR",0.,2.05,zBar,0,"ONLY",dm,4);
1528
1529   //------------------------------------------------------
1530   //  TPc Lower "S" Sectors 
1531   //------------------------------------------------------
1532
1533
1534   Float_t inSecLowEdge = fTPCParam->GetInnerRadiusLow();
1535   Float_t inSecUpEdge =  fTPCParam->GetInnerRadiusUp();
1536
1537   dm[0] = inSecLowEdge*TMath::Tan(0.5*innerOpenAngle)-0.01;
1538   dm[1] = inSecUpEdge*TMath::Tan(0.5*innerOpenAngle)-0.01;
1539   dm[2] = 0.5*(250. - 0.3);
1540   dm[3] = 0.5*(inSecUpEdge-inSecLowEdge);  
1541
1542   gMC->Gsvolu("TPLS", "TRD1", idtmed[2], dm, 4); // sensitive 
1543
1544   //----------------------------------------------------------
1545   //  TPc Upper Sectors
1546   //----------------------------------------------------------
1547
1548   Float_t ouSecLowEdge = fTPCParam->GetOuterRadiusLow();
1549   Float_t ouSecUpEdge = fTPCParam->GetOuterRadiusUp();
1550
1551   dm[0] = ouSecLowEdge*TMath::Tan(0.5*outerOpenAngle)-0.01;  
1552   dm[1] = ouSecUpEdge*TMath::Tan(0.5*outerOpenAngle)-0.01;  
1553   dm[2] = 0.5*(250. - 0.3);
1554   dm[3] = 0.5*(ouSecUpEdge-ouSecLowEdge);
1555
1556   gMC->Gsvolu("TPUS", "TRD1", idtmed[2], dm, 4); // sensitive
1557
1558
1559
1560
1561     gMC->Gsvolu("TPSS","TRD1",idtmed[2],dm,0); // sensitive
1562
1563     Int_t nofStrips,nstr;
1564     Float_t r1,r2,zs;
1565     Float_t stripThick = 0.01; // 100 microns
1566     Float_t deadSpace;
1567
1568     // inner sector
1569
1570
1571     // if all lower sectors selected define only 1 strip
1572
1573     nofStrips=((fSecAL <0)||(fSecAL>=0 && fSens<0)) ? 1 : fTPCParam->GetNRowLow(); 
1574     deadSpace = fTPCParam->GetInnerWireMount();
1575
1576     dm[2] = 0.5*(250. - 0.3);
1577     dm[3] = 0.5 * stripThick;  
1578
1579
1580     for(nstr=0;nstr<nofStrips;nstr++){
1581
1582       r1 = fTPCParam->GetPadRowRadiiLow(nstr);
1583       r2 = r1 + stripThick;     
1584       dm[0] = r1 * TMath::Tan(0.5*innerOpenAngle) - deadSpace;
1585       dm[1] = r2 * TMath::Tan(0.5*innerOpenAngle) - deadSpace;
1586       zs = -inSecLowEdge -0.5*(inSecUpEdge-inSecLowEdge);
1587       zs += r1;
1588       zs += dm[3];
1589     
1590       gMC->Gsposp("TPSS", nstr+1, "TPLS", 0., 0., zs, 0, "ONLY", dm, 4);
1591
1592
1593     }
1594
1595     // strips only if several upper sectors selected end fSens > 0
1596
1597     if(fSecAU >=0 && fSens >0){
1598
1599     Int_t nsSave = nofStrips;
1600
1601     // outer sector
1602
1603     nofStrips = fTPCParam->GetNRowUp();
1604     deadSpace = fTPCParam->GetOuterWireMount();
1605
1606     dm[2] = 0.5*(250. - 0.3);
1607     dm[3] = 0.5 * stripThick;
1608
1609   
1610     for(nstr=0;nstr<nofStrips;nstr++){
1611     
1612       r1 = fTPCParam->GetPadRowRadiiUp(nstr); 
1613       r2 = r1 + stripThick;
1614       dm[0] = r1 * TMath::Tan(0.5*outerOpenAngle) - deadSpace;
1615       dm[1] = r2 * TMath::Tan(0.5*outerOpenAngle) - deadSpace;
1616       zs = -ouSecLowEdge -0.5*(ouSecUpEdge-ouSecLowEdge);
1617       zs += r1;
1618       zs += dm[3];
1619
1620       gMC->Gsposp("TPSS", nstr+1+nsSave, "TPUS", 0., 0., zs, 0, "ONLY", dm, 4);
1621
1622      }    
1623     }
1624
1625   //-------------------------------------------------------
1626   //  positioning of the empty spaces into the main wheel
1627   //  and readout chambers and sectors into the drift gas
1628   //-------------------------------------------------------
1629
1630   Float_t rCenter,xc,yc;
1631   Float_t rInner,rOuter; // center of the inner and outer chamber
1632
1633   rCenter = rLow+dR;
1634
1635   rInner = 108.07;
1636   rOuter = 190.68;
1637
1638   for(Int_t ns=0; ns<nInnerSector;ns++){
1639
1640     phi1 = ns * innerOpenAngle + innerAngleShift;
1641     phi1 *= kRaddeg; // in degrees
1642
1643     phi1 = (Float_t)TMath::Nint(phi1) + 270.;
1644
1645     if (phi1 > 360.) phi1 -= 360.;
1646
1647     theta1 = 90.;
1648     phi2   = 90.;
1649     theta2 = 180.;
1650     phi3   = ns * innerOpenAngle + innerAngleShift;
1651     phi3 *= kRaddeg; // in degrees
1652
1653     phi3 = (Float_t)TMath::Nint(phi3);
1654       
1655     if(phi3 > 360.) phi3 -= 360.;
1656
1657     theta3 = 90.;
1658
1659     // "holes"->End plate
1660
1661     xc = rCenter*TMath::Cos(phi3*kDegrad);
1662     yc = rCenter*TMath::Sin(phi3*kDegrad);
1663
1664     AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
1665
1666     gMC->Gspos("TESR",ns+1,"TPMW",xc,yc,0.,idrotm[nRotMat],"ONLY");
1667
1668     // TSCE->TSWC (services wheel volumes)
1669
1670     xc = 166.142*TMath::Cos(phi3*kDegrad);
1671     yc = 166.142*TMath::Sin(phi3*kDegrad);
1672
1673     gMC->Gspos("TSCE",ns+1,"TSWC",xc,yc,0.,idrotm[nRotMat],"ONLY");
1674     gMC->Gspos("TWES",ns+1,"TSSW",xc,yc,0.,idrotm[nRotMat],"ONLY");
1675
1676     // readout chambers->TDGN (drift gas)
1677
1678     xc = rInner*TMath::Cos(phi3*kDegrad);
1679     yc = rInner*TMath::Sin(phi3*kDegrad);
1680
1681     gMC->Gspos("TIRC",ns+1,"TDGN",xc,yc,252.,idrotm[nRotMat],"ONLY");
1682
1683     // here lower sectors 
1684
1685     if(fSecAL <0){
1686
1687       // all lower sectors are positioned
1688
1689       gMC->Gspos("TPLS",ns+1,"TDGN",xc,yc,125.15,idrotm[nRotMat],"ONLY");
1690       gMC->
1691         Gspos("TPLS",ns+nInnerSector+1,"TDGN",xc,yc,-125.15,idrotm[nRotMat],"ONLY");
1692     }
1693     else{
1694
1695       // only selected sectors are positioned (up to 6 sectors)
1696
1697       for(Int_t sel=0;sel<6;sel++){
1698
1699         if(fSecLows[sel] == ns){
1700           gMC->Gspos("TPLS",ns+1,"TDGN",xc,yc,125.15,idrotm[nRotMat],"ONLY");
1701         }
1702         else if(fSecLows[sel] == ns+nInnerSector){
1703          gMC->
1704           Gspos("TPLS",ns+nInnerSector+1,"TDGN",xc,yc,-125.15,idrotm[nRotMat],"ONLY");
1705         }
1706       }
1707     } // lower sectors finished
1708      
1709     xc = rOuter*TMath::Cos(phi3*kDegrad);
1710     yc = rOuter*TMath::Sin(phi3*kDegrad);
1711
1712     gMC->Gspos("TORC",ns+1,"TDGN",xc,yc,252.1,idrotm[nRotMat],"ONLY");
1713
1714     // here upper sectors 
1715
1716     if(fSecAU <0){
1717
1718       // all upper sectors
1719
1720       gMC->Gspos("TPUS",ns+1,"TDGN",xc,yc,125.15,idrotm[nRotMat],"ONLY");
1721       gMC->
1722         Gspos("TPUS",ns+nOuterSector+1,"TDGN",xc,yc,-125.15,idrotm[nRotMat],"ONLY");
1723     }
1724     else{
1725
1726       // only selected sectors (up to 12)
1727
1728       for(Int_t sel=0;sel<12;sel++){
1729         if(fSecUps[sel] == ns+2*nInnerSector){
1730           gMC->Gspos("TPUS",ns+1,"TDGN",xc,yc,125.15,idrotm[nRotMat],"ONLY");
1731         }         
1732         else if(fSecUps[sel] == ns+2*nInnerSector+nOuterSector){
1733          gMC->
1734           Gspos("TPUS",ns+nOuterSector+1,"TDGN",xc,yc,-125.15,idrotm[nRotMat],"ONLY"); 
1735         }
1736       }
1737     } // upper sectors finished
1738
1739     nRotMat++;
1740
1741     theta2 = 0.; // reflection, needed for readout chambers!
1742
1743     AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
1744
1745     xc = rInner*TMath::Cos(phi3*kDegrad);
1746     yc = rInner*TMath::Sin(phi3*kDegrad);
1747
1748     gMC->Gspos("TIRC",ns+nInnerSector+1,"TDGN",xc,yc,-252.,idrotm[nRotMat],"ONLY");
1749
1750     xc = rOuter*TMath::Cos(phi3*kDegrad);
1751     yc = rOuter*TMath::Sin(phi3*kDegrad);
1752
1753     gMC->Gspos("TORC",ns+nOuterSector+1,"TDGN",xc,yc,-252.1,idrotm[nRotMat],"ONLY");
1754
1755     nRotMat++;
1756
1757
1758   } 
1759
1760   // reflection matrix
1761
1762   theta1 = 90.;
1763   phi1   = 0.;
1764   theta2 = 90.;
1765   phi2   = 270.;
1766   theta3 = 180.;
1767   phi3   = 0.;
1768
1769   AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
1770
1771
1772   // TPMW->TPC
1773
1774   gMC->Gspos("TPMW",1,"TPC ",0.,0.,256.6,0,"ONLY");
1775   gMC->Gspos("TPMW",2,"TPC ",0.,0.,-256.6,idrotm[nRotMat],"ONLY");
1776   gMC->Gspos("TPEW",1,"TPC ",0.,0.,257.65,0,"ONLY");
1777   gMC->Gspos("TPEW",2,"TPC ",0.,0.,-257.65,0,"ONLY");
1778
1779
1780
1781   //-------------------------------------------------------
1782   // Tpc High Voltage Membrane - NOMEX honeycomb
1783   //-------------------------------------------------------
1784
1785   dm[0]=0.,
1786   dm[1]=360.;
1787   dm[2]=18.;
1788   dm[3]=2.;
1789
1790   //
1791
1792   dm[4]= -0.3;
1793   dm[5]= 81.156;
1794   dm[6]= 253.386;
1795
1796   //
1797
1798   dm[7]= 0.3;
1799   dm[8]= dm[5];
1800   dm[9]= dm[6];
1801
1802   gMC->Gsvolu("THVM","PGON",idtmed[6],dm,10);
1803
1804   gMC->Gspos("THVM",1,"TDGN",0.,0.,0.,0,"ONLY");
1805
1806   //----------------------------------------------------------
1807   // TPc Support Rods - MAKROLON
1808   //----------------------------------------------------------
1809
1810   dm[0]= 0.9;
1811   dm[1]= 1.2;
1812   dm[2]= 126.65;
1813
1814   gMC->Gsvolu("TPSR","TUBE",idtmed[7],dm,3);
1815
1816   for(Int_t nrod=1;nrod<18;nrod++){
1817     Float_t angle=innerOpenAngle*(Float_t)nrod;
1818
1819     xc=82.4*TMath::Cos(angle);
1820     yc=82.4*TMath::Sin(angle);
1821
1822     gMC->Gspos("TPSR",nrod,"TDGN",xc,yc,126.95,0,"ONLY");
1823     gMC->Gspos("TPSR",nrod+17,"TDGN",xc,yc,-126.95,0,"ONLY");
1824
1825     xc=254.2*TMath::Cos(angle);
1826     yc=254.2*TMath::Sin(angle);
1827
1828     gMC->Gspos("TPSR",nrod+34,"TDGN",xc,yc,126.95,0,"ONLY");
1829     gMC->Gspos("TPSR",nrod+51,"TDGN",xc,yc,-126.95,0,"ONLY");    
1830
1831   }
1832
1833   //----------------------------------------------------------
1834   // Tpc High Voltage rod - MAKROLON + Copper cable
1835   //----------------------------------------------------------
1836
1837   // rod with cable (Left)
1838
1839   dm[0]=0.;
1840   dm[1]=2.25;
1841   dm[2]=126.65;
1842
1843   gMC->Gsvolu("THVL","TUBE",idtmed[7],dm,3);
1844
1845   // HV cable
1846  
1847   dm[0]=0.;
1848   dm[1]=0.3;
1849   dm[2]=126.65;
1850
1851   gMC->Gsvolu("THVC","TUBE",idtmed[10],dm,3);
1852
1853   // empty space
1854
1855   dm[0]=0.3;
1856   dm[1]=1.;
1857   dm[2]=126.65;
1858
1859   gMC->Gsvolu("THVE","TUBE",idtmed[1],dm,3);
1860
1861   gMC->Gspos("THVC",1,"THVL",0.,0.,0.,0,"ONLY");
1862   gMC->Gspos("THVE",1,"THVL",0.,0.,0.,0,"ONLY");
1863
1864   // rod without cable
1865
1866   dm[0]=1.8;
1867   dm[1]=2.25;
1868   dm[2]=126.65;
1869
1870   gMC->Gsvolu("THVR","TUBE",idtmed[7],dm,3);
1871
1872   
1873   
1874   gMC->Gspos("THVL",1,"TDGN",82.4,0.,-126.95,0,"ONLY");
1875   gMC->Gspos("THVL",2,"TDGN",254.2,0.,-126.95,0,"ONLY");
1876
1877   gMC->Gspos("THVR",1,"TDGN",82.4,0.,126.95,0,"ONLY");
1878   gMC->Gspos("THVR",2,"TDGN",254.2,0.,126.95,0,"ONLY");  
1879   
1880
1881
1882   gMC->Gspos("TDGN",1,"TPC ",0.,0.,0.,0,"ONLY"); 
1883
1884   // services wheel cover -> wheel
1885
1886
1887   gMC->Gspos("TSWC",1,"TSSW",0.,0.,4.5,0,"ONLY");
1888   gMC->Gspos("TSWC",2,"TSSW",0.,0.,-4.5,0,"ONLY");
1889
1890
1891   // put the wheel into the TPC
1892
1893   gMC->Gspos("TSSW",1,"TPC ",0.,0.,278.7,0,"ONLY");
1894   gMC->Gspos("TSSW",2,"TPC ",0.,0.,-278.7,0,"ONLY");
1895
1896   gMC->Gsord("TPMW",6);
1897   if(fSecAL >=0)  gMC->Gsord("TPLS",3);
1898   if(fSecAU >=0 && fSens >0)  gMC->Gsord("TPUS",3);
1899   gMC->Gsord("TDGN",6);
1900   gMC->Gsord("TSSW",6);
1901   gMC->Gsord("TSWC",6);
1902
1903   // put the TPC into ALIC (main mother volume)
1904
1905   gMC->Gspos("TPC ", 1, "ALIC", 0, 0, 0, 0, "ONLY");  
1906
1907 } // end of function
1908  
1909 //_____________________________________________________________________________
1910 void AliTPCv2::DrawDetector()
1911 {
1912   //
1913   // Draw a shaded view of the Time Projection Chamber version 1
1914   //
1915
1916   // Set everything unseen
1917   gMC->Gsatt("*", "seen", -1);
1918   // 
1919   // Set ALIC mother transparent
1920   gMC->Gsatt("ALIC","SEEN",0);
1921   //
1922   // Set the volumes visible
1923   //
1924
1925   gMC->Gsatt("TPC ","SEEN",0);
1926   gMC->Gsatt("TOIN","SEEN",1);
1927   gMC->Gsatt("TOIN","COLO",7);
1928   gMC->Gsatt("TPCR","SEEN",0);
1929   gMC->Gsatt("TOCV","SEEN",1);
1930   gMC->Gsatt("TOCV","COLO",4);
1931   gMC->Gsatt("TSA1","SEEN",0);
1932   gMC->Gsatt("TSA2","SEEN",0);
1933   gMC->Gsatt("TSA3","SEEN",0);
1934   gMC->Gsatt("TSA4","SEEN",0);
1935   gMC->Gsatt("TOFC","SEEN",1);
1936   gMC->Gsatt("TOFC","COLO",4);
1937   gMC->Gsatt("TSA5","SEEN",0);
1938   gMC->Gsatt("TSA6","SEEN",0);
1939   gMC->Gsatt("TSA7","SEEN",0);
1940   gMC->Gsatt("TIIN","COLO",7);
1941   gMC->Gsatt("TIIN","SEEN",1);
1942   gMC->Gsatt("TICL","SEEN",0);
1943   gMC->Gsatt("TSA9","SEEN",0);
1944   gMC->Gsatt("TS10","SEEN",0);
1945   gMC->Gsatt("TS11","SEEN",0);
1946   gMC->Gsatt("TS12","SEEN",0);
1947   gMC->Gsatt("TICR","SEEN",0); 
1948   gMC->Gsatt("TS13","SEEN",0);
1949   gMC->Gsatt("TS14","SEEN",0);
1950   gMC->Gsatt("TS15","SEEN",0);
1951   gMC->Gsatt("TS16","SEEN",0);
1952   gMC->Gsatt("TIFC","SEEN",1);
1953   gMC->Gsatt("TIFC","COLO",4); 
1954   gMC->Gsatt("TS17","SEEN",0);
1955   gMC->Gsatt("TS18","SEEN",0);
1956   gMC->Gsatt("TS19","SEEN",0);
1957   gMC->Gsatt("TS21","SEEN",0);
1958   gMC->Gsatt("TS22","SEEN",0);
1959   gMC->Gsatt("TS23","SEEN",0);
1960   gMC->Gsatt("TS24","SEEN",0);
1961   gMC->Gsatt("TDGN","SEEN",0);
1962   gMC->Gsatt("TIRC","SEEN",0);
1963   gMC->Gsatt("TIC1","SEEN",1);
1964   gMC->Gsatt("TIPP","SEEN",0);
1965   gMC->Gsatt("TIC3","SEEN",0);
1966   gMC->Gsatt("TRCE","SEEN",0);
1967   gMC->Gsatt("TPSC","SEEN",0);
1968   gMC->Gsatt("TPCC","SEEN",0);
1969   gMC->Gsatt("TORC","SEEN",0);
1970   gMC->Gsatt("TOPP","SEEN",0);
1971   gMC->Gsatt("TOC3","SEEN",0);
1972   gMC->Gsatt("TOC1","SEEN",1);
1973   gMC->Gsatt("TSSW","SEEN",1);
1974   gMC->Gsatt("TSWC","SEEN",1);
1975   gMC->Gsatt("TSCE","SEEN",1); 
1976   gMC->Gsatt("TSSW","COLO",3);
1977   gMC->Gsatt("TSWC","COLO",3);
1978   gMC->Gsatt("TSCE","COLO",6);
1979   gMC->Gsatt("TWES","SEEN",0);
1980   gMC->Gsatt("TSWB","SEEN",0);
1981   gMC->Gsatt("TPEL","SEEN",0);
1982   gMC->Gsatt("TPMW","SEEN",1);
1983   gMC->Gsatt("TPEW","SEEN",1);
1984   gMC->Gsatt("TESR","SEEN",1);
1985   gMC->Gsatt("TPMW","COLO",12);
1986   gMC->Gsatt("TPEW","COLO",12);
1987   gMC->Gsatt("TWES","COLO",5);
1988   gMC->Gsatt("TIC1","COLO",5);
1989   gMC->Gsatt("TOC1","COLO",5);  
1990   gMC->Gsatt("TESB","SEEN",0);
1991   gMC->Gsatt("TPLS","SEEN",0);
1992   gMC->Gsatt("TPUS","SEEN",0);
1993   gMC->Gsatt("TPSS","SEEN",0);
1994   gMC->Gsatt("THVM","SEEN",1);
1995   gMC->Gsatt("THVM","COLO",11);
1996   gMC->Gsatt("TPSR","SEEN",0);
1997   gMC->Gsatt("THVL","SEEN",0);
1998   gMC->Gsatt("THVC","SEEN",0);
1999   gMC->Gsatt("THVE","SEEN",0);
2000   gMC->Gsatt("THVR","SEEN",0);
2001
2002   //
2003   gMC->Gdopt("hide", "on");
2004   gMC->Gdopt("shad", "on");
2005   gMC->Gsatt("*", "fill", 7);
2006   gMC->SetClipBox(".");
2007   gMC->SetClipBox("TPMW",-300,300,-300,300,254.,270.);
2008   gMC->SetClipBox("TESR",-300,300,-300,300,254.,270.);
2009   gMC->SetClipBox("TSSW",-300,300,-300,300,283.,284.);
2010   gMC->SetClipBox("TSWC",-300,300,-300,300,283.,284.);
2011   gMC->SetClipBox("*", 0, 300, -300, 300, -290, 290);
2012   gMC->DefaultRange();
2013   gMC->Gdraw("alic", 40, 30, 0, 12, 9.5, .025, .025);
2014   gMC->Gdhead(1111, "Time Projection Chamber");
2015   gMC->Gdman(18, 4, "MAN");
2016   gMC->Gdopt("hide","off");
2017 }
2018
2019 //_____________________________________________________________________________
2020 void AliTPCv2::CreateMaterials()
2021 {
2022   //
2023   // Define materials for version 2 of the Time Projection Chamber
2024   //
2025  
2026   AliTPC::CreateMaterials();
2027 }
2028
2029 //_____________________________________________________________________________
2030 void AliTPCv2::Init()
2031 {
2032   //
2033   // Initialises version 2 of the TPC after that it has been built
2034   //
2035
2036   Int_t *idtmed = fIdtmed->GetArray();
2037   
2038   AliTPC::Init();
2039
2040
2041   
2042   fIdSens=gMC->VolId("TPSS");  
2043
2044   fIdLSec=gMC->VolId("TPLS"); // lower sector 
2045   fIdUSec=gMC->VolId("TPUS"); // upper sector
2046
2047   gMC->SetMaxNStep(30000); // max. number of steps increased
2048
2049   gMC->Gstpar(idtmed[2],"LOSS",5); // specific energy loss
2050
2051   printf("*** TPC version 2 initialized ***\n");
2052   printf("Maximum number of steps = %d\n",gMC->GetMaxNStep());
2053
2054   //
2055   
2056 }
2057
2058 //_____________________________________________________________________________
2059 void AliTPCv2::StepManager()
2060 {
2061   //
2062   // Called for every step in the Time Projection Chamber
2063   //
2064
2065   //
2066   // parameters used for the energy loss calculations
2067   //
2068   const Float_t kprim = 14.35; // number of primary collisions per 1 cm
2069   const Float_t kpoti = 20.77e-9; // first ionization potential for Ne/CO2
2070   const Float_t kwIon = 35.97e-9; // energy for the ion-electron pair creation 
2071  
2072  
2073   const Float_t kbig = 1.e10;
2074
2075   Int_t id,copy;
2076   Float_t hits[4];
2077   Int_t vol[2];  
2078   TLorentzVector p;
2079   
2080   vol[1]=0; // preset row number to 0
2081
2082   //
2083
2084   gMC->SetMaxStep(kbig);
2085   
2086   if(!gMC->IsTrackAlive()) return; // particle has disappeared
2087   
2088   Float_t charge = gMC->TrackCharge();
2089   
2090   if(TMath::Abs(charge)<=0.) return; // take only charged particles
2091   
2092   // check the sensitive volume
2093
2094   id = gMC->CurrentVolID(copy); // current volume Id
2095
2096   if(id == fIdLSec){
2097     vol[0] = copy-1; // lower sector number
2098   }
2099   else if(id == fIdUSec){
2100     vol[0] = copy+fTPCParam->GetNInnerSector()-1; // upper sector number
2101   }
2102   else if(id == fIdSens && gMC->IsTrackEntering()){
2103  
2104     // track is entering the sensitive strip
2105     
2106     vol[1]= copy-1; // row number (absolute)
2107    
2108     // sector type
2109  
2110     id = gMC->CurrentVolOffID(1,copy);
2111
2112     if(id == fIdLSec){
2113
2114       // lower sector
2115      
2116       vol[0] = copy-1; // sector number
2117
2118     }
2119     else {
2120    
2121       // upper sector
2122
2123       vol[0] = copy-1+fTPCParam->GetNInnerSector(); // sector number
2124       vol[1] -= fTPCParam->GetNRowLow(); // row number (starts also from 0)  
2125
2126     } 
2127
2128     if(vol[1] == 0){
2129   
2130       // because Jouri wants to have this
2131
2132       gMC->TrackMomentum(p);
2133       hits[0]=p[0];
2134       hits[1]=p[1];
2135       hits[2]=p[2];
2136       hits[3]=0.; // this hit has no energy loss
2137       // new(lhits[fNhits++]) AliTPChit(fIshunt,gAlice->CurrentTrack(),vol,hits);
2138
2139       AddHit(gAlice->CurrentTrack(), vol,hits);  //MI change
2140
2141     }
2142
2143      gMC->TrackPosition(p);
2144      hits[0]=p[0];
2145      hits[1]=p[1];
2146      hits[2]=p[2];
2147      hits[3]=0.; // this hit has no energy loss
2148      // new(lhits[fNhits++]) AliTPChit(fIshunt,gAlice->CurrentTrack(),vol,hits);
2149
2150      AddHit(gAlice->CurrentTrack(), vol,hits);  //MI change    
2151
2152   }
2153   else return;
2154     
2155   //-----------------------------------------------------------------
2156   //  charged particle is in the sensitive volume
2157   //-----------------------------------------------------------------
2158   
2159   if(gMC->TrackStep() > 0) {
2160     
2161     Int_t nel = (Int_t)(((gMC->Edep())-kpoti)/kwIon) + 1;
2162     nel=TMath::Min(nel,300); // 300 electrons corresponds to 10 keV
2163     
2164     gMC->TrackPosition(p);
2165     hits[0]=p[0];
2166     hits[1]=p[1];
2167     hits[2]=p[2];
2168     hits[3]=(Float_t)nel;
2169     
2170     // Add this hit
2171     
2172     // new(lhits[fNhits++]) AliTPChit(fIshunt,gAlice->CurrentTrack(),vol,hits);
2173     if (fHitType&&2){
2174       gMC->TrackMomentum(p);
2175       Float_t momentum = TMath::Sqrt(p[0]*p[0]+p[1]*p[1]);
2176       Float_t precision =   (momentum>0.1) ? 0.002 :0.01;
2177       fTrackHits->SetHitPrecision(precision);
2178     }
2179     AddHit(gAlice->CurrentTrack(), vol,hits);  //MI change 
2180     
2181   } 
2182   
2183   // Stemax calculation for the next step
2184   
2185   Float_t pp;
2186   TLorentzVector mom;
2187   gMC->TrackMomentum(mom);
2188   Float_t ptot=mom.Rho();
2189   Float_t betaGamma = ptot/gMC->TrackMass();
2190   
2191   Int_t pid=gMC->TrackPid();
2192   if((pid==kElectron || pid==kPositron) && ptot > 0.002)
2193     { 
2194       pp = kprim*1.58; // electrons above 20 MeV/c are on the plateau!
2195     }
2196   else
2197     {
2198
2199       betaGamma = TMath::Max(betaGamma,(Float_t)7.e-3); // protection against too small bg
2200       pp=kprim*BetheBloch(betaGamma); 
2201    
2202       if(TMath::Abs(charge) > 1.) pp *= (charge*charge);
2203     }
2204   
2205   Float_t random[1];
2206   gMC->Rndm(random,1); // good, old GRNDM from Geant3
2207   
2208   Double_t rnd = (Double_t)random[0];
2209   
2210   gMC->SetMaxStep(-TMath::Log(rnd)/pp);
2211   
2212 }
2213
2214 //_____________________________________________________________________________
2215 Float_t AliTPCv2::BetheBloch(Float_t bg)
2216 {
2217   //
2218   // Bethe-Bloch energy loss formula
2219   //
2220   const Double_t kp1=0.76176e-1;
2221   const Double_t kp2=10.632;
2222   const Double_t kp3=0.13279e-4;
2223   const Double_t kp4=1.8631;
2224   const Double_t kp5=1.9479;
2225
2226   Double_t dbg = (Double_t) bg;
2227
2228   Double_t beta = dbg/TMath::Sqrt(1.+dbg*dbg);
2229
2230   Double_t aa = TMath::Power(beta,kp4);
2231   Double_t bb = TMath::Power(1./dbg,kp5);
2232
2233   bb=TMath::Log(kp3+bb);
2234   
2235   return ((Float_t)((kp2-aa-bb)*kp1/aa));
2236 }
2237
2238