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 *
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 **************************************************************************/
21 #include "AliMUONResponseV0.h"
22 #include "AliSegmentation.h"
25 ClassImp(AliMUONResponseV0)
27 //__________________________________________________________________________
28 AliMUONResponseV0::AliMUONResponseV0()
31 // Default constructor
36 //__________________________________________________________________________
37 void AliMUONResponseV0::SetSqrtKx3AndDeriveKx2Kx4(Float_t SqrtKx3)
39 // Set to "SqrtKx3" the Mathieson parameter K3 ("fSqrtKx3")
40 // in the X direction, perpendicular to the wires,
41 // and derive the Mathieson parameters K2 ("fKx2") and K4 ("fKx4")
42 // in the same direction
44 fKx2 = TMath::Pi() / 2. * (1. - 0.5 * fSqrtKx3);
45 Float_t cx1 = fKx2 * fSqrtKx3 / 4. / TMath::ATan(Double_t(fSqrtKx3));
46 fKx4 = cx1 / fKx2 / fSqrtKx3;
49 //__________________________________________________________________________
50 void AliMUONResponseV0::SetSqrtKy3AndDeriveKy2Ky4(Float_t SqrtKy3)
52 // Set to "SqrtKy3" the Mathieson parameter K3 ("fSqrtKy3")
53 // in the Y direction, along the wires,
54 // and derive the Mathieson parameters K2 ("fKy2") and K4 ("fKy4")
55 // in the same direction
57 fKy2 = TMath::Pi() / 2. * (1. - 0.5 * fSqrtKy3);
58 Float_t cy1 = fKy2 * fSqrtKy3 / 4. / TMath::ATan(Double_t(fSqrtKy3));
59 fKy4 = cy1 / fKy2 / fSqrtKy3;
62 Float_t AliMUONResponseV0::IntPH(Float_t eloss)
64 // Calculate charge from given ionization energy loss
66 nel= Int_t(eloss*1.e9/27.4);
69 for (Int_t i=1;i<=nel;i++) {
71 while(!arg) arg = gRandom->Rndm();
72 charge -= fChargeSlope*TMath::Log(arg);
76 // -------------------------------------------
78 Float_t AliMUONResponseV0::IntXY(AliSegmentation * segmentation)
80 // Calculate charge on current pad according to Mathieson distribution
82 const Float_t kInversePitch = 1/fPitch;
84 // Integration limits defined by segmentation model
86 Float_t xi1, xi2, yi1, yi2;
87 segmentation->IntegrationLimits(xi1,xi2,yi1,yi2);
88 xi1=xi1*kInversePitch;
89 xi2=xi2*kInversePitch;
90 yi1=yi1*kInversePitch;
91 yi2=yi2*kInversePitch;
93 // The Mathieson function
94 Double_t ux1=fSqrtKx3*TMath::TanH(fKx2*xi1);
95 Double_t ux2=fSqrtKx3*TMath::TanH(fKx2*xi2);
97 Double_t uy1=fSqrtKy3*TMath::TanH(fKy2*yi1);
98 Double_t uy2=fSqrtKy3*TMath::TanH(fKy2*yi2);
101 return Float_t(4.*fKx4*(TMath::ATan(ux2)-TMath::ATan(ux1))*
102 fKy4*(TMath::ATan(uy2)-TMath::ATan(uy1)));
105 Int_t AliMUONResponseV0::DigitResponse(Int_t digit, AliMUONTransientDigit* /*where*/)
107 // add white noise and do zero-suppression and signal truncation
108 // Float_t meanNoise = gRandom->Gaus(1, 0.2);
109 // correct noise for slat chambers;
110 // one more field to add to AliMUONResponseV0 to allow different noises ????
111 Float_t meanNoise = gRandom->Gaus(1., 0.2);
112 Float_t noise = gRandom->Gaus(0., meanNoise);
113 digit += TMath::Nint(noise);
114 if ( digit <= ZeroSuppression()) digit = 0;
115 // if ( digit > MaxAdc()) digit=MaxAdc();
116 if ( digit > Saturation()) digit=Saturation();