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. *
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8 * documentation strictly for non-commercial purposes is hereby granted *
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14 **************************************************************************/
18 #include "AliMUONConstants.h"
24 #include "AliMpConstants.h"
26 //-----------------------------------------------------------------------------
27 /// \class AliMUONConstants
28 /// This class holds various constants to be used in many places,
29 /// such as the number of tracking and trigger chambers,
30 /// some geometrical constants (to build the initial geometry for simulation)
31 /// and mathieson distribution default values.
32 /// Those constants should as much as possible replace hard-coded values
33 /// which are to be considered strictly illegal in the MUON code (or any code,
35 //-----------------------------------------------------------------------------
38 ClassImp(AliMUONConstants)
41 Int_t AliMUONConstants::fgNTrackingSt = 5;
42 Int_t AliMUONConstants::fgNTriggerCircuit = 234;
43 Int_t AliMUONConstants::fgNDetElem = 228;
44 Int_t AliMUONConstants::fgNGeomModules = 20;
45 Float_t AliMUONConstants::fgkTriggerTofLimit = 75E-9;
47 Float_t AliMUONConstants::fgDefaultChamberZ[14] =
48 {-526.16, -545.24, -676.4, -695.4, // St12
49 -967.5, -998.5, -1276.5, -1307.5, -1406.6, -1437.6,// updated 08/05, EDMS id 335328 (A. Tournaire)
50 -1603.5, -1620.5, -1703.5, -1720.5}; // M1 & M2
53 // These are used by AliMUONConstants::ChamberNumber and must be calculated once
54 // by that method from fgDzCh, fgDzSlat, fgDefaultChamberZ and fgSt345inclination,
55 // so for now we set everything to zero.
56 Float_t AliMUONConstants::fgDefaultChamberMinZ[14] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
57 Float_t AliMUONConstants::fgDefaultChamberMaxZ[14] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
59 Float_t AliMUONConstants::fgDefaultRatioTriggerChamber[4] =
60 {1., 1.01060, 1.06236, 1.07296};
63 Float_t AliMUONConstants::fgSt345inclination = 0.794; // in degrees, rotation axis is X axis
65 Float_t AliMUONConstants::fgDzCh = 15.5/2.;
66 Float_t AliMUONConstants::fgDzSlat = 8.5/2.;
68 Float_t AliMUONConstants::fgSqrtKx3 = 0.7131;
69 Float_t AliMUONConstants::fgSqrtKy3 = 0.7642;
71 Float_t AliMUONConstants::fgSqrtKx3St1 = 0.7000;
72 Float_t AliMUONConstants::fgSqrtKy3St1 = 0.7550;
74 Float_t AliMUONConstants::fgChargeCorrel = 0.11;
75 Float_t AliMUONConstants::fgChargeCorrelSt1 = 1.0; //???
76 Float_t AliMUONConstants::fgPitch = 0.25;
77 Float_t AliMUONConstants::fgPitchSt1 = 0.21;
79 // From Alain TOURNAIRE
80 // ALICE / ALICE Engineering baseline / Dimuonspectrometer (DIS) v7-1
81 // EDMS Id 335328 for "search in EDMS
82 // These are the diameter (Dmin == innner and Dmax - outner) values of the active surface
83 // In the case of Dmax, the value corresponds to the maximum diameter of the active surface with 2pi coverture in phi
84 Float_t AliMUONConstants::fgDmin[7] = { 36.4, 46.2, 63.0, 79.0, 79.0, 98.8, 100.0}; // cm
85 Float_t AliMUONConstants::fgDmax[7] = { 176.6, 229.0, 308.84, 418.2, 522.0, 850.0, 900.0}; // cm
87 Int_t AliMUONConstants::fgMaxZoom = 20;
89 // Defaults parameters for dipole magnet
90 // From ALICE Dimuon - parameters / geometry table,
91 // V7-3 (version 7 created 24/03/2004 updated 25/10/2005)
92 Double_t AliMUONConstants::fgCoilZ = -994.05;
93 Double_t AliMUONConstants::fgCoilL = 502.1;
94 Double_t AliMUONConstants::fgYokeZ = -986.6;
95 Double_t AliMUONConstants::fgYokeL = 309.4;
97 // Defaults parameters for absorber (27/06/07)
98 const Double_t AliMUONConstants::fgkAbsZBeg = -90.;
99 const Double_t AliMUONConstants::fgkAbsZEnd = -505.;
101 // Default trigger chamber resolution (cm)
102 const Double_t AliMUONConstants::fgkTriggerNonBendingReso = 1.;
103 const Double_t AliMUONConstants::fgkTriggerBendingReso = 1.;
105 // Defaults parameters for muon filter (19/11/07)
106 const Double_t AliMUONConstants::fgkMuonFilterZBeg = -1471.;
107 const Double_t AliMUONConstants::fgkMuonFilterZEnd = -1471.-120.;
108 const Double_t AliMUONConstants::fgkMuonFilterX0 = 1.76;
110 // Defaults parameters for track reconstruction
111 Double_t AliMUONConstants::fgChamberThicknessInX0 = 0.03;
113 const Double_t AliMUONConstants::fgkMostProbBendingMomentum = 2.0;
115 //______________________________________________________________________________
116 Int_t AliMUONConstants::NCh()
118 return AliMpConstants::NofChambers();
121 //______________________________________________________________________________
122 Int_t AliMUONConstants::NTrackingCh()
124 return AliMpConstants::NofTrackingChambers();
127 //______________________________________________________________________________
128 Int_t AliMUONConstants::ChamberNumber(Float_t z, bool warn)
130 // return chamber number according z position of hit. Should be taken from geometry ?
132 if (fgDefaultChamberMinZ[0] == 0) // Are the min/max Z arrays initialised?
134 // The min and max Z arrays need to be calculated.
135 for (Int_t i = 0; i < NCh(); i++)
137 Float_t a = 0, b = 0;
138 if (4 <= i and i < 10)
140 Float_t dzAngle = TMath::Tan(TMath::Pi()*St345Inclination()/180.) * Rmax(i/2);
141 // We add 2.5mm since Rmax is an under-estimate.
142 a = DefaultChamberZ(i) + DzSlat() + DzCh() + dzAngle + 0.25;
143 b = DefaultChamberZ(i) - DzSlat() - DzCh() - dzAngle - 0.25;
147 a = DefaultChamberZ(i) + DzSlat();
148 b = DefaultChamberZ(i) - DzSlat();
150 fgDefaultChamberMinZ[i] = TMath::Min(a, b);
151 fgDefaultChamberMaxZ[i] = TMath::Max(a, b);
155 // We can apply a binary search for the chamber since the fgDefaultChamberMinZ and
156 // fgDefaultChamberMaxZ arrays are ordered.
157 Int_t mini = 0, maxi = NCh()-1;
160 Int_t iChamber = (maxi + mini) / 2;
161 if (z < fgDefaultChamberMinZ[iChamber])
163 else if (z > fgDefaultChamberMaxZ[iChamber])
166 // We are between min and max Z of chamber number iChamber so we found our chamber.
170 if (warn) AliWarningClass(Form("No chamber number found for z = %f",z));