1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
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 *
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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 **************************************************************************/
18 Revision 1.3 2003/12/29 18:40:39 hristov
19 Copy/paste error corrected
21 Revision 1.2 2003/12/29 17:26:01 hristov
22 Using enum to initaialize static ints in the header file, the initialization of static floats moved to the implementation file
24 Revision 1.1 2003/12/29 15:18:03 decaro
25 TOF geometry updating (addition of AliTOFGeometry)
27 Revision 0.01 2003/12/04 S.Arcelli
28 Revision 0.02 2003/12/10 S.Arcelli:
29 Implement Global methods GetPos & GetDetID
30 Revision 0.03 2003/12/14 S.Arcelli
31 Set Phi range [-180,180]->[0,360]
32 Revision 0.03 2004/4/05 S.Arcelli
33 Implement Global methods IsInsideThePad
38 #include <Riostream.h>
39 ///////////////////////////////////////////////////////////////////////////////
41 // TOF Geometry class //
43 ///////////////////////////////////////////////////////////////////////////////
46 #include "AliTOFGeometry.h"
48 ClassImp(AliTOFGeometry)
50 const Int_t AliTOFGeometry::fgkTimeDiff = 25000;// Min signal separation (ps)
52 const Float_t AliTOFGeometry::fgkxTOF = 371.; // Inner radius of the TOF for Reconstruction (cm)
53 const Float_t AliTOFGeometry::fgkRmin = 370.; // Inner radius of the TOF (cm)
54 const Float_t AliTOFGeometry::fgkRmax = 399; // Outer radius of the TOF (cm)
55 const Float_t AliTOFGeometry::fgkZlenA = 106.0;// length (cm) of the A module
56 const Float_t AliTOFGeometry::fgkZlenB = 141.0;// length (cm) of the B module
57 const Float_t AliTOFGeometry::fgkZlenC = 177.5;// length (cm) of the C module
58 const Float_t AliTOFGeometry::fgkXPad = 2.5; // Pad size in the x direction (cm)
59 const Float_t AliTOFGeometry::fgkZPad = 3.5; // Pad size in the z direction (cm)
60 const Float_t AliTOFGeometry::fgkMaxhZtof = 371.5;// Max half z-size of TOF (cm)
63 const Float_t AliTOFGeometry::fgkSigmaForTail1= 2.;//Sig1 for simulation of TDC tails
64 const Float_t AliTOFGeometry::fgkSigmaForTail2= 0.5;//Sig2 for simulation of TDC tails
65 const Float_t AliTOFGeometry::fgkSpeedOfLight = 0.299792458;// c (10^9 m/s)
66 const Float_t AliTOFGeometry::fgkPionMass = 0.13957;// pion mass (Gev/c^2)
67 const Float_t AliTOFGeometry::fgkKaonMass = 0.49368;// kaon mass (Gev/c^2)
68 const Float_t AliTOFGeometry::fgkProtonMass = 0.93827;// proton mass (Gev/c^2)
69 const Float_t AliTOFGeometry::fgkElectronMass = 0.00051;// electron mass (Gev/c^2)
70 const Float_t AliTOFGeometry::fgkMuonMass = 0.10566;// muon mass (Gev/c^2)
73 const Float_t AliTOFGeometry::fgkDprecMin = 0.0000075;//num.prec.tolerance on Thmin
74 const Float_t AliTOFGeometry::fgkDprecMax = 0.0000100;//num.prec.tolerance on Thma
75 const Float_t AliTOFGeometry::fgkDprecCen = 0.0000005;//num.prec.tolerance on <Theta>
77 //_____________________________________________________________________________
78 AliTOFGeometry::AliTOFGeometry()
81 // AliTOFGeometry default constructor
87 //_____________________________________________________________________________
88 AliTOFGeometry::~AliTOFGeometry()
91 // AliTOFGeometry destructor
95 //_____________________________________________________________________________
96 void AliTOFGeometry::Init()
99 // Initialize strip Tilt Angles and Heights
101 // Strips Tilt Angles
103 Float_t const kangles[kNPlates][kMaxNstrip] ={
105 {44.494, 43.725, 42.946, 42.156, 41.357, 40.548, 39.729, 38.899,
106 38.060, 37.211, 36.353, 35.484, 34.606, 33.719, 32.822, 31.916,
107 31.001, 30.077, 29.144, 28.202 },
109 {26.884, 25.922, 24.952, 23.975, 22.989, 22.320, 21.016, 20.309,
110 19.015, 18.270, 16.989, 16.205, 14.941, 14.117, 12.871, 12.008,
111 10.784, 9.8807, 8.681, 0.0 },
113 { 7.5835, 6.4124, 5.4058, 4.2809, 3.2448, 2.1424, 1.078, -0., -1.078,
114 -2.1424, -3.2448, -4.2809, -5.4058, -6.4124, -7.5835, 0.0, 0.0, 0.0,
117 {-8.681, -9.8807, -10.784, -12.008, -12.871, -14.117, -14.941, -16.205,
118 -16.989, -18.27, -19.015, -20.309, -21.016, -22.32, -22.989,
119 -23.975, -24.952, -25.922, -26.884, 0. },
121 {-28.202, -29.144, -30.077, -31.001, -31.916, -32.822, -33.719, -34.606,
122 -35.484, -36.353, -37.211, -38.06, -38.899, -39.729, -40.548,
123 -41.357, -42.156, -42.946, -43.725, -44.494 }};
128 Float_t const kheights[kNPlates][kMaxNstrip]= {
130 {-5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5,
131 -5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5 },
133 {-6.3, -7.1, -7.9, -8.7, -9.5, -3, -9.5, -3, -9.5, -3,
134 -9.5, -3.0, -9.5, -3.0, -9.5, -3, -9.5, -3, -9 , 0.},
136 { -3, -9, -4.5, -9, -4.5, -9, -4.5, -9, -4.5, -9,
137 -4.5, -9, -4.5, -9, -3, 0.0, 0.0, 0.0, 0.0, 0.0 },
139 { -9, -3, -9.5, -3, -9.5, -3, -9.5, -3, -9.5, -3, -9.5,
140 -3, -9.5, -3, -9.5, -8.7, -7.9, -7.1, -6.3, 0. },
142 {-5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5,
143 -5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5, -5.5 }};
146 // Deposit in fAngles, fHeights
148 for (Int_t iplate = 0; iplate < kNPlates; iplate++) {
149 for (Int_t istrip = 0; istrip < kMaxNstrip; istrip++) {
150 fAngles[iplate][istrip] = kangles[iplate][istrip];
151 fHeights[iplate][istrip] = kheights[iplate][istrip];
155 fPhiSec = 360./kNSectors;
158 //_____________________________________________________________________________
159 Float_t AliTOFGeometry::DistanceToPad(Int_t *det, Float_t *pos)
162 // Returns distance of space point with coor pos (x,y,z) (cm) wrt
163 // pad with Detector Indices idet (iSect,iPlate,iStrip,iPadX,iPadZ)
166 //Transform pos into Sector Frame
172 Float_t radius = TMath::Sqrt(x*x+y*y);
173 Float_t phi=TMath::ATan2(y,x);
174 if(phi<0) phi=2.*TMath::Pi()+phi;
175 // Get the local angle in the sector philoc
176 Float_t angle = phi*kRaddeg-( Int_t (kRaddeg*phi/20.) + 0.5)*fPhiSec;
177 Float_t xs = radius*TMath::Cos(angle/kRaddeg);
178 Float_t ys = radius*TMath::Sin(angle/kRaddeg);
181 // Do the same for the selected pad
186 Float_t padRadius = TMath::Sqrt(g[0]*g[0]+g[1]*g[1]);
187 Float_t padPhi=TMath::ATan2(g[1],g[0]);
188 if(padPhi<0) padPhi=2.*TMath::Pi()+padPhi;
189 // Get the local angle in the sector philoc
190 Float_t padAngle = padPhi*kRaddeg-( Int_t (padPhi*kRaddeg/20.)+ 0.5) * fPhiSec;
191 Float_t padxs = padRadius*TMath::Cos(padAngle/kRaddeg);
192 Float_t padys = padRadius*TMath::Sin(padAngle/kRaddeg);
193 Float_t padzs = g[2];
195 //Now move to local pad coordinate frame. Translate:
197 Float_t xt = xs-padxs;
198 Float_t yt = ys-padys;
199 Float_t zt = zs-padzs;
202 Float_t alpha = GetAngles(det[1],det[2]);
203 Float_t xr = xt*TMath::Cos(alpha/kRaddeg)+zt*TMath::Sin(alpha/kRaddeg);
205 Float_t zr = -xt*TMath::Sin(alpha/kRaddeg)+zt*TMath::Cos(alpha/kRaddeg);
207 Float_t dist = TMath::Sqrt(xr*xr+yr*yr+zr*zr);
213 //_____________________________________________________________________________
214 Bool_t AliTOFGeometry::IsInsideThePad(Int_t *det, Float_t *pos)
217 // Returns true if space point with coor pos (x,y,z) (cm) falls
218 // inside pad with Detector Indices idet (iSect,iPlate,iStrip,iPadX,iPadZ)
221 Bool_t isInside=false;
224 //Transform pos into Sector Frame
230 Float_t radius = TMath::Sqrt(x*x+y*y);
231 Float_t phi=TMath::ATan2(y,x);
232 if(phi<0) phi=2.*TMath::Pi()+phi;
233 // Get the local angle in the sector philoc
234 Float_t angle = phi*kRaddeg-( Int_t (kRaddeg*phi/20.) + 0.5) *fPhiSec;
235 Float_t xs = radius*TMath::Cos(angle/kRaddeg);
236 Float_t ys = radius*TMath::Sin(angle/kRaddeg);
239 // Do the same for the selected pad
244 Float_t padRadius = TMath::Sqrt(g[0]*g[0]+g[1]*g[1]);
245 Float_t padPhi=TMath::ATan2(g[1],g[0]);
246 if(padPhi<0) padPhi=2.*TMath::Pi()+padPhi;
247 // Get the local angle in the sector philoc
248 Float_t padAngle = padPhi*kRaddeg-( Int_t (padPhi*kRaddeg/20.)+ 0.5) * fPhiSec;
249 Float_t padxs = padRadius*TMath::Cos(padAngle/kRaddeg);
250 Float_t padys = padRadius*TMath::Sin(padAngle/kRaddeg);
251 Float_t padzs = g[2];
253 //Now move to local pad coordinate frame. Translate:
255 Float_t xt = xs-padxs;
256 Float_t yt = ys-padys;
257 Float_t zt = zs-padzs;
260 Float_t alpha = GetAngles(det[1],det[2]);
261 Float_t xr = xt*TMath::Cos(alpha/kRaddeg)+zt*TMath::Sin(alpha/kRaddeg);
263 Float_t zr = -xt*TMath::Sin(alpha/kRaddeg)+zt*TMath::Cos(alpha/kRaddeg);
265 if(fabs(xr)<=0.75 && fabs(yr)<= (fgkXPad*0.5) && fabs(zr)<= (fgkZPad*0.5))
271 //_____________________________________________________________________________
272 void AliTOFGeometry::GetPos(Int_t *det, Float_t *pos)
275 // Returns space point coor (x,y,z) (cm) for Detector
276 // Indices (iSect,iPlate,iStrip,iPadX,iPadZ)
284 //_____________________________________________________________________________
285 void AliTOFGeometry::GetDetID( Float_t *pos, Int_t *det)
288 // Returns Detector Indices (iSect,iPlate,iStrip,iPadX,iPadZ)
289 // space point coor (x,y,z) (cm)
292 det[0]=GetSector(pos);
293 det[1]=GetPlate(pos);
294 det[2]=GetStrip(pos);
299 //_____________________________________________________________________________
300 Float_t AliTOFGeometry::GetX(Int_t *det)
303 // Returns X coordinate (cm)
306 Int_t isector = det[0];
307 Int_t iplate = det[1];
308 Int_t istrip = det[2];
309 Int_t ipadz = det[3];
310 Int_t ipadx = det[4];
312 // Find out distance d on the plane wrt median phi:
313 Float_t d = (ipadx+0.5)*fgkXPad-(kNpadX*fgkXPad)*0.5;
315 // The radius r in xy plane:
316 Float_t r = (fgkRmin+fgkRmax)/2.+fHeights[iplate][istrip]+
317 (ipadz-0.5)*fgkZPad*TMath::Sin(fAngles[iplate][istrip]/kRaddeg)-0.25;
319 // local azimuthal angle in the sector philoc
320 Float_t philoc = TMath:: ATan(d/r);
322 // azimuthal angle in the global frame phi
323 Float_t phi = philoc*kRaddeg+(isector+0.5 )*fPhiSec;
325 Float_t xCoor = r/TMath::Cos(philoc)*TMath::Cos(phi/kRaddeg);
329 //_____________________________________________________________________________
330 Float_t AliTOFGeometry::GetY(Int_t *det)
333 // Returns Y coordinate (cm)
336 Int_t isector = det[0];
337 Int_t iplate = det[1];
338 Int_t istrip = det[2];
339 Int_t ipadz = det[3];
340 Int_t ipadx = det[4];
342 // Find out distance d on the plane wrt median phi:
343 Float_t d = (ipadx+0.5)*fgkXPad-(kNpadX*fgkXPad)*0.5;
345 // The radius r in xy plane:
346 Float_t r = (fgkRmin+fgkRmax)/2.+fHeights[iplate][istrip]+
347 (ipadz-0.5)*fgkZPad*TMath::Sin(fAngles[iplate][istrip]/kRaddeg)-0.25;
349 // local azimuthal angle in the sector philoc
350 Float_t philoc = TMath:: ATan(d/r);
352 // azimuthal angle in the global frame phi
353 Float_t phi = philoc*kRaddeg+(isector+0.5 )*fPhiSec;
355 Float_t yCoor = r/TMath::Cos(philoc)*TMath::Sin(phi/kRaddeg);
360 //_____________________________________________________________________________
361 Float_t AliTOFGeometry::GetZ(Int_t *det)
364 // Returns Z coordinate (cm)
367 Int_t iplate = det[1];
368 Int_t istrip = det[2];
369 Int_t ipadz = det[3];
372 // The radius r in xy plane:
373 Float_t r = (fgkRmin+fgkRmax)/2.+fHeights[iplate][istrip];
375 Float_t zCoor = r*TMath::Tan(0.5*TMath::Pi()-GetStripTheta(iplate,istrip))-
376 (ipadz-0.5)*fgkZPad*TMath::Cos(fAngles[iplate][istrip]/kRaddeg);
380 //_____________________________________________________________________________
381 Int_t AliTOFGeometry::GetSector(Float_t *pos)
384 // Returns the Sector index
392 Float_t phi = TMath::ATan2(y,x);
393 if(phi<0.) phi=2.*TMath::Pi()+phi;
394 iSect = (Int_t) (phi*kRaddeg/fPhiSec);
399 //_____________________________________________________________________________
400 Int_t AliTOFGeometry::GetPadX(Float_t *pos)
403 // Returns the Pad index along X
412 Int_t isector = GetSector(pos);
414 cout << "Detector Index could not be determined" << endl;
416 Int_t iplate = GetPlate(pos);
418 cout << "Detector Index could not be determined" << endl;
420 Int_t istrip = GetStrip(pos);
422 cout << "Detector Index could not be determined" << endl;
426 Float_t rho=TMath::Sqrt(x*x+y*y);
427 Float_t phi = TMath::ATan2(y,x);
428 if(phi<0.) phi=2.*TMath::Pi()+phi;
430 // Get the local angle in the sector philoc
431 Float_t philoc = phi*kRaddeg-(isector+0.5)*fPhiSec;
432 philoc*=TMath::Pi()/180.;
433 // theta projected on the median of the sector
434 Float_t theta = TMath::ATan2(rho*TMath::Cos(philoc),z);
435 // The radius r in xy plane:
436 Float_t r = (fgkRmin+fgkRmax)/2.+fHeights[iplate][istrip]+
437 (theta-GetStripTheta(iplate, istrip))/
438 (GetMaxStripTheta(iplate, istrip)-GetMinStripTheta(iplate, istrip))
439 * 2.*fgkZPad*TMath::Sin(fAngles[iplate][istrip]/kRaddeg)-0.25;
441 // Find out distance projected onto the strip plane
442 Float_t d = (r*TMath::Tan(philoc)+(kNpadX*fgkXPad)*0.5);
444 iPadX = (Int_t) ( d/fgkXPad);
448 //_____________________________________________________________________________
449 Int_t AliTOFGeometry::GetPlate(Float_t *pos)
452 // Returns the Plate index
456 Int_t isector = GetSector(pos);
458 cout << "Detector Index could not be determined" << endl;
465 Float_t rho=TMath::Sqrt(x*x+y*y);
466 Float_t phi=TMath::ATan2(y,x);
467 if(phi<0) phi=2.*TMath::Pi()+phi;
468 // Get the local angle in the sector philoc
469 Float_t philoc = phi*kRaddeg-(isector+0.5)*fPhiSec;
470 philoc*=TMath::Pi()/180.;
471 // theta projected on the median of the sector
472 Float_t theta=TMath::ATan2(rho*TMath::Cos(philoc),z);
474 for (Int_t i=0; i<kNPlates; i++){
475 if ( GetMaxPlateTheta(i) >= theta &&
476 GetMinPlateTheta(i) <= theta)iPlate=i;
482 //_____________________________________________________________________________
483 Int_t AliTOFGeometry::GetStrip(Float_t *pos)
486 // Returns the Strip index
492 Int_t isector = GetSector(pos);
494 cout << "Detector Index could not be determined" << endl;
496 Int_t iplate = GetPlate(pos);
498 cout << "Detector Index could not be determined" << endl;
507 if(iplate==0 || iplate == 4)nstrips=kNStripC;
508 if(iplate==1 || iplate == 3)nstrips=kNStripB;
509 if(iplate==2) nstrips=kNStripA;
511 Float_t rho=TMath::Sqrt(x*x+y*y);
512 Float_t phi=TMath::ATan2(y,x);
513 if(phi<0) phi=2.*TMath::Pi()+phi;
514 // Get the local angle in the sector philoc
515 Float_t philoc = phi*kRaddeg-(isector+0.5)*fPhiSec;
516 philoc*=TMath::Pi()/180.;
517 // theta projected on the median of the sector
518 Float_t theta=TMath::ATan2(rho*TMath::Cos(philoc),z);
520 for (Int_t istrip=0; istrip<nstrips; istrip++){
523 GetMaxStripTheta(iplate,istrip) >= theta
525 GetMinStripTheta(iplate,istrip) <= theta ) iStrip = istrip;
531 //_____________________________________________________________________________
532 Int_t AliTOFGeometry::GetPadZ(Float_t *pos)
535 // Returns the Pad index along Z
539 Int_t isector = GetSector(pos);
541 cout << "Detector Index could not be determined" << endl;
543 Int_t iplate = GetPlate(pos);
545 cout << "Detector Index could not be determined" << endl;
547 Int_t istrip = GetStrip(pos);
549 cout << "Detector Index could not be determined" << endl;
557 Float_t rho=TMath::Sqrt(x*x+y*y);
558 Float_t phi=TMath::ATan2(y,x);
559 if(phi<0) phi=2.*TMath::Pi()+phi;
560 Float_t philoc = phi*kRaddeg-(isector+0.5)*fPhiSec;
561 philoc*=TMath::Pi()/180.;
562 Float_t theta=TMath::ATan2(rho*TMath::Cos(philoc),z);
564 if (theta >= GetStripTheta(iplate, istrip))iPadZ=1;
569 //_____________________________________________________________________________
570 Float_t AliTOFGeometry::GetMinPlateTheta(Int_t iPlate)
573 // Returns the minimum theta angle of a given plate iPlate (rad)
580 if(iPlate==0)delta = -1. ;
581 if(iPlate==1)delta = -0.5;
582 if(iPlate==3)delta = +0.5;
583 if(iPlate==4)delta = +1. ;
585 Float_t z=(fgkRmin+2.)*TMath::Tan(fAngles[iPlate][index]/kRaddeg)+delta;
586 Float_t r=(fgkRmin+fgkRmax)/2.+fHeights[iPlate][index];
587 z =z+fgkZPad*TMath::Cos(fAngles[iPlate][index]/kRaddeg);
588 r =r-fgkZPad*TMath::Sin(fAngles[iPlate][index]/kRaddeg);
590 Float_t thmin = 0.5*TMath::Pi()-TMath::ATan(z/r)-fgkDprecMin;
594 //_____________________________________________________________________________
595 Float_t AliTOFGeometry::GetMaxPlateTheta(Int_t iPlate)
598 // Returns the maximum theta angle of a given plate iPlate (rad)
601 if(iPlate==0 ||iPlate == 4)index=kNStripC-1;
602 if(iPlate==1 ||iPlate == 3)index=kNStripB-1;
603 if(iPlate==2) index=kNStripA-1;
606 if(iPlate==0)delta = -1. ;
607 if(iPlate==1)delta = -0.5;
608 if(iPlate==3)delta = +0.5;
609 if(iPlate==4)delta = +1. ;
611 Float_t z=(fgkRmin+2.)*TMath::Tan(fAngles[iPlate][index]/kRaddeg)+delta;
612 Float_t r=(fgkRmin+fgkRmax)/2.+fHeights[iPlate][index];
613 z =z-fgkZPad*TMath::Cos(fAngles[iPlate][index]/kRaddeg);
614 r= r+fgkZPad*TMath::Sin(fAngles[iPlate][index]/kRaddeg);
616 Float_t thmax = 0.5*TMath::Pi()-TMath::ATan(z/r)+fgkDprecMax;
620 //_____________________________________________________________________________
621 Float_t AliTOFGeometry::GetMaxStripTheta(Int_t iPlate, Int_t iStrip)
624 // Returns the maximum theta angle of a given strip iStrip (rad)
629 if(iPlate==0)delta = -1. ;
630 if(iPlate==1)delta = -0.5;
631 if(iPlate==3)delta = +0.5;
632 if(iPlate==4)delta = +1. ;
634 Float_t r =(fgkRmin+fgkRmax)/2.+fHeights[iPlate][iStrip];
635 Float_t z =(fgkRmin+2.)*TMath::Tan(fAngles[iPlate][iStrip]/kRaddeg)+delta;
636 z = z-fgkZPad*TMath::Cos(fAngles[iPlate][iStrip]/kRaddeg);
637 r = r+fgkZPad*TMath::Sin(fAngles[iPlate][iStrip]/kRaddeg);
638 Float_t thmax =0.5*TMath::Pi()-TMath::ATan(z/r)+fgkDprecMax;
643 //_____________________________________________________________________________
644 Float_t AliTOFGeometry::GetMinStripTheta(Int_t iPlate, Int_t iStrip)
647 // Returns the minimum theta angle of a given Strip iStrip (rad)
652 if(iPlate==0)delta = -1. ;
653 if(iPlate==1)delta = -0.5;
654 if(iPlate==3)delta = +0.5;
655 if(iPlate==4)delta = +1. ;
658 Float_t r =(fgkRmin+fgkRmax)/2.+fHeights[iPlate][iStrip];
659 Float_t z =(fgkRmin+2.)*TMath::Tan(fAngles[iPlate][iStrip]/kRaddeg)+delta;
660 z =z+fgkZPad*TMath::Cos(fAngles[iPlate][iStrip]/kRaddeg);
661 r =r-fgkZPad*TMath::Sin(fAngles[iPlate][iStrip]/kRaddeg);
662 Float_t thmin =0.5*TMath::Pi()-TMath::ATan(z/r)-fgkDprecMin;
669 //_____________________________________________________________________________
670 Float_t AliTOFGeometry::GetStripTheta(Int_t iPlate, Int_t iStrip)
673 // returns the median theta angle of a given strip iStrip (rad)
678 if(iPlate==0)delta = -1. ;
679 if(iPlate==1)delta = -0.5;
680 if(iPlate==3)delta = +0.5;
681 if(iPlate==4)delta = +1. ;
683 Float_t r =(fgkRmin+fgkRmax)/2.+fHeights[iPlate][iStrip];
684 Float_t z =(fgkRmin+2.)*TMath::Tan(fAngles[iPlate][iStrip]/kRaddeg)+delta;
685 Float_t theta =0.5*TMath::Pi()-TMath::ATan(z/r);
687 if(theta > 0.5*TMath::Pi() )theta+=fgkDprecCen;
688 if(theta < 0.5*TMath::Pi() )theta-=fgkDprecCen;