1 #ifndef ALIQUENCHINGWEIGHTS_H
2 #define ALIQUENCHINGWEIGHTS_H
3 /* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * See cxx source for full Copyright notice */
8 //----------------------------------------------------------------------------
9 // Implementation of the class to calculate the parton energy loss
10 // Based on the "BDMPS" quenching weights by C.A.Salgado and U.A.Wiedemann
13 // C.A.Salgado and U.A.Wiedemann, Phys.Rev.D68 (2003) 014008 [hep-ph/0302184]
14 // A.Dainese, Eur.Phys.J.C, in press, [nucl-ex/0312005]
16 // Origin: C. Loizides constantin.loizides@cern.ch
17 // A. Dainese andrea.dainese@pd.infn.it
18 //----------------------------------------------------------------------------
23 class AliQuenchingWeights : public TObject {
25 enum kECMethod {kDefault=0,kReweight=1,kReweightCont=2};
27 AliQuenchingWeights();
28 AliQuenchingWeights(const AliQuenchingWeights& a);
29 virtual ~AliQuenchingWeights();
32 Int_t SampleEnergyLoss();
33 Int_t SampleEnergyLoss(Int_t ipart, Double_t R);
35 Double_t GetELossRandom(Int_t ipart, Double_t length, Double_t e=1.e10) const;
36 Double_t CalcQuenchedEnergy(Int_t ipart, Double_t length, Double_t e) const;
37 Double_t GetELossRandom(Int_t ipart, TH1F *hell, Double_t e=1.e10) const;
38 Double_t CalcQuenchedEnergy(Int_t ipart, TH1F *hell, Double_t e) const;
39 Double_t GetELossRandomK(Int_t ipart, Double_t I0, Double_t I1, Double_t e=1.e10);
40 Double_t CalcQuenchedEnergyK(Int_t ipart, Double_t I0, Double_t I1, Double_t e);
41 Double_t GetELossRandomKFast(Int_t ipart, Double_t I0, Double_t I1, Double_t e=1.e10);
42 Double_t GetELossRandomKFastR(Int_t ipart, Double_t R, Double_t wc, Double_t e=1.e10);
43 Double_t CalcQuenchedEnergyKFast(Int_t ipart, Double_t I0, Double_t I1, Double_t e);
45 Double_t GetDiscreteWeight(Int_t ipart, Double_t I0, Double_t I1);
46 Double_t GetDiscreteWeightR(Int_t ipart, Double_t R);
47 void GetZeroLossProb(Double_t &p,Double_t &prw,Double_t &prw_cont,
48 Int_t ipart,Double_t I0,Double_t I1,Double_t e=1.e10);
49 void GetZeroLossProbR(Double_t &p,Double_t &prw, Double_t &prw_cont,
50 Int_t ipart,Double_t R,Double_t wc,Double_t e=1.e10);
52 //multiple soft scattering approximation
53 Int_t InitMult(const Char_t *contall="$(ALICE_ROOT)/FASTSIM/data/cont_mult.all",
54 const Char_t *discall="$(ALICE_ROOT)/FASTSIM/data/disc_mult.all");
56 //single hard scattering approximation
57 Int_t InitSingleHard(const Char_t *contall="$(ALICE_ROOT)/FASTSIM/data/cont_lin.all",
58 const Char_t *discall="$(ALICE_ROOT)/FASTSIM/data/disc_lin.all");
60 Int_t CalcMult(Int_t ipart, Double_t rrrr,Double_t xxxx,
61 Double_t &continuous,Double_t &discrete) const;
62 Int_t CalcMult(Int_t ipart,
63 Double_t w, Double_t qtransp, Double_t length,
64 Double_t &continuous,Double_t &discrete) const;
65 Int_t CalcSingleHard(Int_t ipart, Double_t rrrr,Double_t xxxx,
66 Double_t &continuous,Double_t &discrete) const;
67 Int_t CalcSingleHard(Int_t ipart,
68 Double_t w, Double_t mu, Double_t length,
69 Double_t &continuous,Double_t &discrete) const;
71 Double_t CalcWC(Double_t q, Double_t l) const
72 {return 0.5*q*l*l*fgkConvFmToInvGeV;}
74 Double_t CalcWCbar(Double_t mu, Double_t l) const
75 {return 0.5*mu*mu*l*fgkConvFmToInvGeV;}
77 Double_t CalcWC(Double_t l) const
78 {if(fMultSoft) return CalcWC(fQTransport,l);
79 else return CalcWCbar(fMu,l);}
81 Double_t CalcWCk(Double_t I1) const
82 {if(fMultSoft) return CalcWCk(fK,I1);
83 else return -1;} //not implemented!
85 Double_t CalcWCk(Double_t k, Double_t I1) const
86 {if(fMultSoft) return k*I1/fgkConvFmToInvGeV;
87 else return -1;} //not implemented!
89 Double_t CalcR(Double_t wc, Double_t l) const;
91 Double_t CalcRk(Double_t I0, Double_t I1) const
92 {return CalcRk(fK,I0,I1);}
94 Double_t CalcRk(Double_t k, Double_t I0, Double_t I1) const;
96 Double_t CalcQk(Double_t I0, Double_t I1) const
97 {return CalcQk(fK,I0,I1);}
99 Double_t CalcQk(Double_t k, Double_t I0, Double_t I1) const
100 {return I0*I0/2./I1/fgkConvFmToInvGeV/fgkConvFmToInvGeV*k;}
102 Double_t CalcLk(Double_t i0, Double_t i1) const
105 Int_t CalcLengthMax(Double_t q) const
106 {Double_t l3max=fgkRMax/.5/q/fgkConvFmToInvGeV/fgkConvFmToInvGeV;
107 return (Int_t)TMath::Power(l3max,1./3.);}
109 const TH1F* GetHisto(Int_t ipart,Double_t length) const;
111 void SetMu(Double_t m=1.) {fMu=m;}
112 void SetQTransport(Double_t q=1.) {fQTransport=q;}
113 void SetK(Double_t k=4.e5) {fK=k;} //about 1 GeV^2/fm
114 void SetECMethod(kECMethod type=kDefault);
115 void SetLengthMax(Int_t l=20) {fLengthMax=l;}
117 Float_t GetMu() const {return fMu;}
118 Float_t GetQTransport() const {return fQTransport;}
119 Float_t GetK() const {return fK;}
120 Bool_t GetECMethod() const {return fECMethod;}
121 Bool_t GetTablesLoaded() const {return fTablesLoaded;}
122 Bool_t GetMultSoft() const {return fMultSoft;}
123 Int_t GetLengthMax() const {return fLengthMax;}
125 TH1F* ComputeQWHisto (Int_t ipart,Double_t medval,Double_t length) const;
126 TH1F* ComputeQWHistoX(Int_t ipart,Double_t medval,Double_t length) const;
127 TH1F* ComputeQWHistoX(Int_t ipart,Double_t R) const;
128 TH1F* ComputeELossHisto(Int_t ipart,Double_t medval,Double_t l,Double_t e=1.e10) const;
129 TH1F* ComputeELossHisto(Int_t ipart,Double_t medval,TH1F *hEll,Double_t e=1.e10) const;
130 TH1F* ComputeELossHisto(Int_t ipart,Double_t R) const;
132 Double_t GetMeanELoss(Int_t ipart,Double_t medval,Double_t l) const;
133 Double_t GetMeanELoss(Int_t ipart,Double_t medval,TH1F *hEll) const;
134 Double_t GetMeanELoss(Int_t ipart,Double_t R) const;
136 void PlotDiscreteWeights(Double_t len=4) const;
137 void PlotContWeights(Int_t itype,Double_t len) const;
138 void PlotContWeightsVsL(Int_t itype,Double_t medval) const;
139 void PlotAvgELoss(Double_t len ,Double_t e=1.e10) const;
140 void PlotAvgELoss(TH1F *hEll,Double_t e=1.e10) const;
141 void PlotAvgELossVsL(Double_t e=1.e10) const;
142 void PlotAvgELossVsPt(Double_t medval,Double_t len) const;
143 void PlotAvgELossVsPt(Double_t medval,TH1F *hEll) const;
146 Int_t GetIndex(Double_t len) const;
148 static const Double_t fgkConvFmToInvGeV; //conversion factor
149 static const Int_t fgkBins; //number of bins for hists
150 static const Double_t fgkMaxBin; //max. value of wc
151 static const Double_t fgkRMax; //max. tabled value of R
153 static Int_t fgCounter;//static instance counter
154 Int_t fInstanceNumber; //instance number of class
156 Bool_t fMultSoft; //approximation type
157 kECMethod fECMethod; //energy constraint method
158 Double_t fQTransport; //transport coefficient [GeV^2/fm]]
159 Double_t fMu; //Debye screening mass
160 Double_t fK; //proportional constant [fm]
161 Int_t fLengthMax; //maximum length
162 Int_t fLengthMaxOld; //maximum length used for histos
164 //discrete and cont part of quenching for
165 //both parton type and different lengths
169 // data strucs for tables
170 Double_t fxx[400]; //sampled energy quark
171 Double_t fxxg[400]; //sampled energy gluon
172 Double_t fdaq[34]; //discrete weight quark
173 Double_t fdag[34]; //discrete weight gluon
174 Double_t fcaq[34][261]; //continuous weights quarks
175 Double_t fcag[34][261]; //continuous weights gluons
176 Double_t frrr[34]; //r value quark
177 Double_t frrrg[34]; //r value gluon
178 Bool_t fTablesLoaded; //tables loaded
180 ClassDef(AliQuenchingWeights,1) // Base class for Quenching Weights