[u/mrichter/AliRoot.git] / EVGEN / AliGenHIJINGparaBa.cxx

/**************************************************************************
 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
 *                                                                        *
 * Author: The ALICE Off-line Project.                                    *
 * Contributors are mentioned in the code where appropriate.              *
 *                                                                        *
 * Permission to use, copy, modify and distribute this software and its   *
 * documentation strictly for non-commercial purposes is hereby granted   *
 * without fee, provided that the above copyright notice appears in all   *
 * copies and that both the copyright notice and this permission notice   *
 * appear in the supporting documentation. The authors make no claims     *
 * about the suitability of this software for any purpose. It is          *
 * provided "as is" without express or implied warranty.                  *
 **************************************************************************/

/*
$Log$
Revision 1.1.4.1  2003/04/14 17:33:50  hristov
Merging with v3-09-08 (part1)

Revision 1.2  2003/01/14 10:50:18  alibrary
Cleanup of STEER coding conventions

Revision 1.1  2002/01/08 09:47:28  morsch
HIJING parameterisation including baryons, first commit.

*/
///////////////////////////////////////////////////////////////////
// Parameterisation of pi, K, n and p eta and pt distributions   //
// eta: according to HIJING (shadowing + quenching)              //
// pT : according to CDF measurement at 1.8 TeV                  //
// Author: andreas.morsch@cern.ch                                //
//                                                               //
///////////////////////////////////////////////////////////////////

#include <TArrayF.h>
#include <TF1.h>
#include <TPDGCode.h>

#include "AliConst.h"
#include "AliGenEventHeader.h"
#include "AliGenHIJINGparaBa.h"
#include "AliRun.h"

ClassImp(AliGenHIJINGparaBa)


static Double_t ptpi(Double_t *px, Double_t *)
{
  //
  //     PT-PARAMETERIZATION CDF, PRL 61(88) 1819
  //     POWER LAW FOR PT > 500 MEV
  //     MT SCALING BELOW (T=160 MEV)
  //
  const Double_t kp0 = 1.3;
  const Double_t kxn = 8.28;
  const Double_t kxlim=0.5;
  const Double_t kt=0.160;
  const Double_t kxmpi=0.139;
  const Double_t kb=1.;
  Double_t y, y1, xmpi2, ynorm, a;
  Double_t x=*px;
  //
  y1=TMath::Power(kp0/(kp0+kxlim),kxn);
  xmpi2=kxmpi*kxmpi;
  ynorm=kb*(TMath::Exp(-sqrt(kxlim*kxlim+xmpi2)/kt));
  a=ynorm/y1;
  if (x > kxlim)
    y=a*TMath::Power(kp0/(kp0+x),kxn);
  else
    y=kb*TMath::Exp(-sqrt(x*x+xmpi2)/kt);
  return y*x;
}

//_____________________________________________________________________________
static Double_t ptscal(Double_t pt, Int_t np)
{
    //    SCALING EN MASSE PAR RAPPORT A PTPI
    //     MASS PI,K,ETA,RHO,OMEGA,ETA',PHI
    const Double_t khm[10] = {.13957,.493,.5488,.769,.7826,.958,1.02,0,0,0};
    //     VALUE MESON/PI AT 5 GEV
    const Double_t kfmax[10]={1.,0.3,0.55,1.0,1.0,1.0,1.0,0,0,0};
    np--;
    Double_t f5=TMath::Power(((
	sqrt(100.018215)+2.)/(sqrt(100.+khm[np]*khm[np])+2.0)),12.3);
    Double_t fmax2=f5/kfmax[np];
    // PIONS
    Double_t ptpion=100.*ptpi(&pt, (Double_t*) 0);
    Double_t fmtscal=TMath::Power(((
	sqrt(pt*pt+0.018215)+2.)/ (sqrt(pt*pt+khm[np]*khm[np])+2.0)),12.3)/ 
	fmax2;
    return fmtscal*ptpion;
}

//_____________________________________________________________________________
static Double_t ptka( Double_t *px, Double_t *)
{
    //
    // pt parametrisation for k
    //
    return ptscal(*px,2);
}


//_____________________________________________________________________________
static Double_t etapic( Double_t *py, Double_t *)
{
  //
  // eta parametrisation for pi
  //
    const Double_t ka1    = 4913.;
    const Double_t ka2    = 1819.;
    const Double_t keta1  = 0.22;
    const Double_t keta2  = 3.66;
    const Double_t kdeta1 = 1.47;
    const Double_t kdeta2 = 1.51;
    Double_t y=TMath::Abs(*py);
    //
    Double_t ex1 = (y-keta1)*(y-keta1)/(2*kdeta1*kdeta1);
    Double_t ex2 = (y-keta2)*(y-keta2)/(2*kdeta2*kdeta2);
    return ka1*TMath::Exp(-ex1)+ka2*TMath::Exp(-ex2);
}

//_____________________________________________________________________________
static Double_t etakac( Double_t *py, Double_t *)
{
    //
    // eta parametrisation for ka
    //
    const Double_t ka1    = 497.6;
    const Double_t ka2    = 215.6;
    const Double_t keta1  = 0.79;
    const Double_t keta2  = 4.09;
    const Double_t kdeta1 = 1.54;
    const Double_t kdeta2 = 1.40;
    Double_t y=TMath::Abs(*py);
    //
    Double_t ex1 = (y-keta1)*(y-keta1)/(2*kdeta1*kdeta1);
    Double_t ex2 = (y-keta2)*(y-keta2)/(2*kdeta2*kdeta2);
    return ka1*TMath::Exp(-ex1)+ka2*TMath::Exp(-ex2);
}

 static Double_t ptbaryon( Double_t *px, Double_t *)
{
// baryons
//                pt-distribution
//____________________________________________________________

  return ptscal(*px,7);  //  7==> Baryon in the PtScal function
}

 static Double_t etabaryon( Double_t *py, Double_t *)
{
// eta-distribution
//____________________________________________________________
    const Float_t p0 =  1.10343e+02;
    const Float_t p1 =  1.73247e+01;
    const Float_t p2 = -7.23808e+00;
    const Float_t p3 =  4.48334e-01;
    const Double_t y = TMath::Abs(*py);
//
    return (p0+p1*y+p2*y*y+p3*y*y*y)/20.;
}

AliGenHIJINGparaBa::AliGenHIJINGparaBa()
  :AliGenHIJINGpara()
{
    //
    // Default constructor
    //
    fName="HIGINGparaBa";
    fTitle="HIJING Parametrisation Particle Generator with Baryons";
    fETAba = 0;
    fPtba  = 0;
}

//_____________________________________________________________________________
AliGenHIJINGparaBa::AliGenHIJINGparaBa(Int_t npart)
  :AliGenHIJINGpara(npart)
{
  // 
  // Standard constructor
  //
    fName="HIGINGparaBa";
    fTitle="HIJING Parametrisation Particle Generator with Baryons";
    fETAba = 0;
    fPtba  = 0;
}

//_____________________________________________________________________________
AliGenHIJINGparaBa::~AliGenHIJINGparaBa()
{
  //
  // Standard destructor
  //
    delete fPtba;
    delete fETAba;
}

//_____________________________________________________________________________
void AliGenHIJINGparaBa::Init()
{
  //
  // Initialise the HIJING parametrisation
  //
    Float_t etaMin =-TMath::Log(TMath::Tan(
	TMath::Min((Double_t)fThetaMax/2,TMath::Pi()/2-1.e-10)));
    Float_t etaMax = -TMath::Log(TMath::Tan(
	TMath::Max((Double_t)fThetaMin/2,1.e-10)));
    fPtpi   = new TF1("ptpi",&ptpi,0,20,0);
    fPtka   = new TF1("ptka",&ptka,0,20,0);
    fPtba   = new TF1("ptbaryon",&ptbaryon,0,20,0);
    fETApic = new TF1("etapic",&etapic,etaMin,etaMax,0);
    fETAkac = new TF1("etakac",&etakac,etaMin,etaMax,0);
    fETAba  = new TF1("etabaryon",&etabaryon,etaMin,etaMax,0);

    TF1 *etaPic0 = new TF1("etapic",&etapic,    -7, 7, 0);
    TF1 *etaKac0 = new TF1("etakac",&etakac,    -7, 7, 0);
    TF1 *etaBar0 = new TF1("etabar",&etabaryon, -7, 7, 0);
    
    TF1 *ptPic0  = new TF1("ptpi",  &ptpi,     0., 15., 0);
    TF1 *ptKac0  = new TF1("ptka",  &ptka,     0., 15., 0);
    TF1 *ptBar0  = new TF1("ptbar", &ptbaryon, 0., 15., 0);

    Float_t intETApi  = etaPic0->Integral(-0.5, 0.5);
    Float_t intETAka  = etaKac0->Integral(-0.5, 0.5);
    Float_t intETAba  = etaBar0->Integral(-0.5, 0.5);

    Float_t scalePi   = 6979./(intETApi/1.5);
    Float_t scaleKa   =  657./(intETAka/2.0);
    Float_t scaleBa   =  364./(intETAba/2.0);

//  Fraction of events corresponding to the selected pt-range    
    Float_t intPt    = (0.837*ptPic0->Integral(0, 15)+
			0.105*ptKac0->Integral(0, 15)+
                        0.058*ptBar0->Integral(0, 15));
    Float_t intPtSel = (0.837*ptPic0->Integral(fPtMin, fPtMax)+
			0.105*ptKac0->Integral(fPtMin, fPtMax)+
	                0.058*ptBar0->Integral(fPtMin, fPtMax));
    Float_t ptFrac   = intPtSel/intPt;

//  Fraction of events corresponding to the selected eta-range    
    Float_t intETASel  = (scalePi*etaPic0->Integral(etaMin, etaMax)+
			  scaleKa*etaKac0->Integral(etaMin, etaMax)+
	                  scaleBa*etaBar0->Integral(etaMin, etaMax));
//  Fraction of events corresponding to the selected phi-range    
    Float_t phiFrac    = (fPhiMax-fPhiMin)/2/TMath::Pi();

    fParentWeight = Float_t(fNpart)/(intETASel*ptFrac*phiFrac);
    
    printf("%s: The number of particles in the selected kinematic region corresponds to %f percent of a full event \n", 
	   ClassName(),100.*fParentWeight);

// Issue warning message if etaMin or etaMax are outside the alowed range 
// of the parametrization
    if (etaMin < -8.001 || etaMax > 8.001) {
	printf("\n \n WARNING FROM AliGenHIJINGParaBa !");
	printf("\n YOU ARE USING THE PARAMETERISATION OUTSIDE ");	
	printf("\n THE ALLOWED PSEUDORAPIDITY RANGE (-8. - 8.)");	    
	printf("\n YOUR LIMITS: %f %f \n \n ", etaMin, etaMax);
    }
}

//_____________________________________________________________________________
void AliGenHIJINGparaBa::Generate()
{
  //
  // Generate one trigger
  //

  
    const Float_t kBorne1 = 0.837;
    const Float_t kBorne2 = kBorne1+0.105;
    
    Float_t polar[3]= {0,0,0};
    //
    const Int_t kPions[3]   = {kPi0, kPiPlus, kPiMinus};
    const Int_t kKaons[4]   = {kK0Long, kK0Short, kKPlus, kKMinus};
    const Int_t kBaryons[4] = {kProton, kProtonBar, kNeutron, kNeutronBar};
    //
    Float_t origin[3];
    Float_t pt, pl, ptot;
    Float_t phi, theta;
    Float_t p[3];
    Int_t i, part, nt, j;
    //
    TF1 *ptf;
    TF1 *etaf;
    //
    Float_t random[6];
    //
    for (j=0;j<3;j++) origin[j]=fOrigin[j];

    if(fVertexSmear == kPerEvent) {
	Float_t dv[3];
	dv[2] = 1.e10;
	while(TMath::Abs(dv[2]) > fCutVertexZ*fOsigma[2]) {
	    Rndm(random,6);
	    for (j=0; j < 3; j++) {
		dv[j] = fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
		    TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
	    }
	}
	for (j=0; j < 3; j++) origin[j] += dv[j];
    } // if kPerEvent
    TArrayF eventVertex;
    eventVertex.Set(3);
    eventVertex[0] = origin[0];
    eventVertex[1] = origin[1];
    eventVertex[2] = origin[2];

    for(i=0;i<fNpart;i++) {
	while(1) {
	    Rndm(random,3);
	    if(random[0] < kBorne1) {
		part  = kPions[Int_t (random[1]*3)];
		ptf   = fPtpi;
		etaf  = fETApic;
	    } else if (random[0] < kBorne2) {
		part  = kKaons[Int_t (random[1]*4)];
		ptf   = fPtka;
		etaf  = fETAkac;
	    } else {
		part  = kBaryons[Int_t (random[1]*4)];
		ptf   = fPtba;
		etaf  = fETAba;
	    }
	    
	    phi=fPhiMin+random[2]*(fPhiMax-fPhiMin);
	    theta=2*TMath::ATan(TMath::Exp(-etaf->GetRandom()));
	    if(theta<fThetaMin || theta>fThetaMax) continue;
	    pt=ptf->GetRandom();
	    pl=pt/TMath::Tan(theta);
	    ptot=TMath::Sqrt(pt*pt+pl*pl);
	    if(ptot<fPMin || ptot>fPMax) continue;
	    p[0]=pt*TMath::Cos(phi);
	    p[1]=pt*TMath::Sin(phi);
	    p[2]=pl;
	    if(fVertexSmear==kPerTrack) {
		Rndm(random,6);
		for (j=0;j<3;j++) {
		    origin[j]=fOrigin[j]+fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
			TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
		}
	    }
	    SetTrack(fTrackIt,-1,part,p,origin,polar,0,kPPrimary,nt,fParentWeight);
	    break;
	} // while(1)
    } // Particle loop
// Header
    AliGenEventHeader* header = new AliGenEventHeader("HIJINGparam");
// Event Vertex
    header->SetPrimaryVertex(eventVertex);
    gAlice->SetGenEventHeader(header); 
}
Commit	Line	Data
388f2c07	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	$Log$
88cb7938	18	Revision 1.1.4.1 2003/04/14 17:33:50 hristov
	19	Merging with v3-09-08 (part1)
	20
	21	Revision 1.2 2003/01/14 10:50:18 alibrary
	22	Cleanup of STEER coding conventions
	23
116cbefd	24	Revision 1.1 2002/01/08 09:47:28 morsch
	25	HIJING parameterisation including baryons, first commit.
	26
388f2c07	27	*/
	28	///////////////////////////////////////////////////////////////////
	29	// Parameterisation of pi, K, n and p eta and pt distributions //
	30	// eta: according to HIJING (shadowing + quenching) //
	31	// pT : according to CDF measurement at 1.8 TeV //
	32	// Author: andreas.morsch@cern.ch //
	33	// //
	34	///////////////////////////////////////////////////////////////////
	35
116cbefd	36	#include <TArrayF.h>
	37	#include <TF1.h>
	38	#include <TPDGCode.h>
	39
	40	#include "AliConst.h"
388f2c07	41	#include "AliGenEventHeader.h"
116cbefd	42	#include "AliGenHIJINGparaBa.h"
388f2c07	43	#include "AliRun.h"
388f2c07	44
	45	ClassImp(AliGenHIJINGparaBa)
	46
	47
	48	static Double_t ptpi(Double_t px, Double_t )
	49	{
	50	//
	51	// PT-PARAMETERIZATION CDF, PRL 61(88) 1819
	52	// POWER LAW FOR PT > 500 MEV
	53	// MT SCALING BELOW (T=160 MEV)
	54	//
	55	const Double_t kp0 = 1.3;
	56	const Double_t kxn = 8.28;
	57	const Double_t kxlim=0.5;
	58	const Double_t kt=0.160;
	59	const Double_t kxmpi=0.139;
	60	const Double_t kb=1.;
	61	Double_t y, y1, xmpi2, ynorm, a;
	62	Double_t x=*px;
	63	//
	64	y1=TMath::Power(kp0/(kp0+kxlim),kxn);
	65	xmpi2=kxmpi*kxmpi;
	66	ynorm=kb(TMath::Exp(-sqrt(kxlimkxlim+xmpi2)/kt));
	67	a=ynorm/y1;
	68	if (x > kxlim)
	69	y=a*TMath::Power(kp0/(kp0+x),kxn);
	70	else
	71	y=kbTMath::Exp(-sqrt(xx+xmpi2)/kt);
	72	return y*x;
	73	}
	74
	75	//_____________________________________________________________________________
	76	static Double_t ptscal(Double_t pt, Int_t np)
	77	{
	78	// SCALING EN MASSE PAR RAPPORT A PTPI
	79	// MASS PI,K,ETA,RHO,OMEGA,ETA',PHI
	80	const Double_t khm[10] = {.13957,.493,.5488,.769,.7826,.958,1.02,0,0,0};
	81	// VALUE MESON/PI AT 5 GEV
	82	const Double_t kfmax[10]={1.,0.3,0.55,1.0,1.0,1.0,1.0,0,0,0};
	83	np--;
	84	Double_t f5=TMath::Power(((
	85	sqrt(100.018215)+2.)/(sqrt(100.+khm[np]*khm[np])+2.0)),12.3);
	86	Double_t fmax2=f5/kfmax[np];
	87	// PIONS
	88	Double_t ptpion=100.ptpi(&pt, (Double_t) 0);
	89	Double_t fmtscal=TMath::Power(((
	90	sqrt(ptpt+0.018215)+2.)/ (sqrt(ptpt+khm[np]*khm[np])+2.0)),12.3)/
	91	fmax2;
	92	return fmtscal*ptpion;
	93	}
	94
	95	//_____________________________________________________________________________
	96	static Double_t ptka( Double_t px, Double_t )
	97	{
	98	//
	99	// pt parametrisation for k
	100	//
	101	return ptscal(*px,2);
	102	}
	103
	104
	105	//_____________________________________________________________________________
	106	static Double_t etapic( Double_t py, Double_t )
	107	{
108	//
109	// eta parametrisation for pi
110	//
111	const Double_t ka1 = 4913.;
112	const Double_t ka2 = 1819.;
113	const Double_t keta1 = 0.22;
114	const Double_t keta2 = 3.66;
115	const Double_t kdeta1 = 1.47;
116	const Double_t kdeta2 = 1.51;
117	Double_t y=TMath::Abs(*py);
118	//
119	Double_t ex1 = (y-keta1)(y-keta1)/(2kdeta1*kdeta1);
120	Double_t ex2 = (y-keta2)(y-keta2)/(2kdeta2*kdeta2);
121	return ka1TMath::Exp(-ex1)+ka2TMath::Exp(-ex2);
122	}
123
124	//_____________________________________________________________________________
125	static Double_t etakac( Double_t py, Double_t )
126	{
127	//
128	// eta parametrisation for ka
129	//
130	const Double_t ka1 = 497.6;
131	const Double_t ka2 = 215.6;
132	const Double_t keta1 = 0.79;
133	const Double_t keta2 = 4.09;
134	const Double_t kdeta1 = 1.54;
135	const Double_t kdeta2 = 1.40;
136	Double_t y=TMath::Abs(*py);
137	//
138	Double_t ex1 = (y-keta1)(y-keta1)/(2kdeta1*kdeta1);
139	Double_t ex2 = (y-keta2)(y-keta2)/(2kdeta2*kdeta2);
140	return ka1TMath::Exp(-ex1)+ka2TMath::Exp(-ex2);
141	}
142
143	static Double_t ptbaryon( Double_t px, Double_t )
144	{
145	// baryons
146	// pt-distribution
147	//____________________________________________________________
148
149	return ptscal(*px,7); // 7==> Baryon in the PtScal function
150	}
151
152	static Double_t etabaryon( Double_t py, Double_t )
153	{
154	// eta-distribution
155	//____________________________________________________________
156	const Float_t p0 = 1.10343e+02;
157	const Float_t p1 = 1.73247e+01;
158	const Float_t p2 = -7.23808e+00;
159	const Float_t p3 = 4.48334e-01;
160	const Double_t y = TMath::Abs(*py);
161	//
162	return (p0+p1y+p2yy+p3yyy)/20.;
163	}
164
165	AliGenHIJINGparaBa::AliGenHIJINGparaBa()
166	:AliGenHIJINGpara()
167	{
168	//
169	// Default constructor
170	//
171	fName="HIGINGparaBa";
172	fTitle="HIJING Parametrisation Particle Generator with Baryons";
173	fETAba = 0;
174	fPtba = 0;
175	}
176
177	//_____________________________________________________________________________
178	AliGenHIJINGparaBa::AliGenHIJINGparaBa(Int_t npart)
179	:AliGenHIJINGpara(npart)
180	{
181	//
182	// Standard constructor
183	//
184	fName="HIGINGparaBa";
185	fTitle="HIJING Parametrisation Particle Generator with Baryons";
186	fETAba = 0;
187	fPtba = 0;
188	}
189
190	//_____________________________________________________________________________
191	AliGenHIJINGparaBa::~AliGenHIJINGparaBa()
192	{
193	//
194	// Standard destructor
195	//
196	delete fPtba;
197	delete fETAba;
198	}
199
200	//_____________________________________________________________________________
201	void AliGenHIJINGparaBa::Init()
202	{
203	//
204	// Initialise the HIJING parametrisation
205	//
206	Float_t etaMin =-TMath::Log(TMath::Tan(
207	TMath::Min((Double_t)fThetaMax/2,TMath::Pi()/2-1.e-10)));
208	Float_t etaMax = -TMath::Log(TMath::Tan(
209	TMath::Max((Double_t)fThetaMin/2,1.e-10)));
210	fPtpi = new TF1("ptpi",&ptpi,0,20,0);
211	fPtka = new TF1("ptka",&ptka,0,20,0);
212	fPtba = new TF1("ptbaryon",&ptbaryon,0,20,0);
213	fETApic = new TF1("etapic",&etapic,etaMin,etaMax,0);
214	fETAkac = new TF1("etakac",&etakac,etaMin,etaMax,0);
215	fETAba = new TF1("etabaryon",&etabaryon,etaMin,etaMax,0);
216
217	TF1 *etaPic0 = new TF1("etapic",&etapic, -7, 7, 0);
218	TF1 *etaKac0 = new TF1("etakac",&etakac, -7, 7, 0);
219	TF1 *etaBar0 = new TF1("etabar",&etabaryon, -7, 7, 0);
220
221	TF1 *ptPic0 = new TF1("ptpi", &ptpi, 0., 15., 0);
222	TF1 *ptKac0 = new TF1("ptka", &ptka, 0., 15., 0);
223	TF1 *ptBar0 = new TF1("ptbar", &ptbaryon, 0., 15., 0);
224
225	Float_t intETApi = etaPic0->Integral(-0.5, 0.5);
226	Float_t intETAka = etaKac0->Integral(-0.5, 0.5);
227	Float_t intETAba = etaBar0->Integral(-0.5, 0.5);
228
229	Float_t scalePi = 6979./(intETApi/1.5);
230	Float_t scaleKa = 657./(intETAka/2.0);
231	Float_t scaleBa = 364./(intETAba/2.0);
232
233	// Fraction of events corresponding to the selected pt-range
234	Float_t intPt = (0.837*ptPic0->Integral(0, 15)+
235	0.105*ptKac0->Integral(0, 15)+
236	0.058*ptBar0->Integral(0, 15));
237	Float_t intPtSel = (0.837*ptPic0->Integral(fPtMin, fPtMax)+
238	0.105*ptKac0->Integral(fPtMin, fPtMax)+
239	0.058*ptBar0->Integral(fPtMin, fPtMax));
240	Float_t ptFrac = intPtSel/intPt;
241
242	// Fraction of events corresponding to the selected eta-range
243	Float_t intETASel = (scalePi*etaPic0->Integral(etaMin, etaMax)+
244	scaleKa*etaKac0->Integral(etaMin, etaMax)+
245	scaleBa*etaBar0->Integral(etaMin, etaMax));
246	// Fraction of events corresponding to the selected phi-range
247	Float_t phiFrac = (fPhiMax-fPhiMin)/2/TMath::Pi();
248
249	fParentWeight = Float_t(fNpart)/(intETASelptFracphiFrac);
250
251	printf("%s: The number of particles in the selected kinematic region corresponds to %f percent of a full event \n",
252	ClassName(),100.*fParentWeight);
253
254	// Issue warning message if etaMin or etaMax are outside the alowed range
255	// of the parametrization
256	if (etaMin < -8.001 \|\| etaMax > 8.001) {
257	printf("\n \n WARNING FROM AliGenHIJINGParaBa !");
258	printf("\n YOU ARE USING THE PARAMETERISATION OUTSIDE ");
259	printf("\n THE ALLOWED PSEUDORAPIDITY RANGE (-8. - 8.)");
260	printf("\n YOUR LIMITS: %f %f \n \n ", etaMin, etaMax);
261	}
262	}
263
264	//_____________________________________________________________________________
265	void AliGenHIJINGparaBa::Generate()
266	{
267	//
268	// Generate one trigger
269	//
270
271
272	const Float_t kBorne1 = 0.837;
273	const Float_t kBorne2 = kBorne1+0.105;
274
275	Float_t polar[3]= {0,0,0};
276	//
277	const Int_t kPions[3] = {kPi0, kPiPlus, kPiMinus};
278	const Int_t kKaons[4] = {kK0Long, kK0Short, kKPlus, kKMinus};
279	const Int_t kBaryons[4] = {kProton, kProtonBar, kNeutron, kNeutronBar};
280	//
281	Float_t origin[3];
282	Float_t pt, pl, ptot;
283	Float_t phi, theta;
284	Float_t p[3];
285	Int_t i, part, nt, j;
286	//
287	TF1 *ptf;
288	TF1 *etaf;
289	//
290	Float_t random[6];
291	//
292	for (j=0;j<3;j++) origin[j]=fOrigin[j];
293
294	if(fVertexSmear == kPerEvent) {
295	Float_t dv[3];
296	dv[2] = 1.e10;
297	while(TMath::Abs(dv[2]) > fCutVertexZ*fOsigma[2]) {
298	Rndm(random,6);
299	for (j=0; j < 3; j++) {
300	dv[j] = fOsigma[j]TMath::Cos(2random[2j]TMath::Pi())*
301	TMath::Sqrt(-2TMath::Log(random[2j+1]));
302	}
303	}
304	for (j=0; j < 3; j++) origin[j] += dv[j];
305	} // if kPerEvent
306	TArrayF eventVertex;
307	eventVertex.Set(3);
308	eventVertex[0] = origin[0];
309	eventVertex[1] = origin[1];
310	eventVertex[2] = origin[2];
311
312	for(i=0;i<fNpart;i++) {
313	while(1) {
314	Rndm(random,3);
315	if(random[0] < kBorne1) {
316	part = kPions[Int_t (random[1]*3)];
317	ptf = fPtpi;
318	etaf = fETApic;
319	} else if (random[0] < kBorne2) {
320	part = kKaons[Int_t (random[1]*4)];
321	ptf = fPtka;
322	etaf = fETAkac;
323	} else {
324	part = kBaryons[Int_t (random[1]*4)];
325	ptf = fPtba;
326	etaf = fETAba;
327	}
328
329	phi=fPhiMin+random[2]*(fPhiMax-fPhiMin);
330	theta=2*TMath::ATan(TMath::Exp(-etaf->GetRandom()));
331	if(theta<fThetaMin \|\| theta>fThetaMax) continue;
332	pt=ptf->GetRandom();
333	pl=pt/TMath::Tan(theta);
334	ptot=TMath::Sqrt(ptpt+plpl);
335	if(ptot<fPMin \|\| ptot>fPMax) continue;
336	p[0]=pt*TMath::Cos(phi);
337	p[1]=pt*TMath::Sin(phi);
338	p[2]=pl;
339	if(fVertexSmear==kPerTrack) {
340	Rndm(random,6);
341	for (j=0;j<3;j++) {
342	origin[j]=fOrigin[j]+fOsigma[j]TMath::Cos(2random[2j]TMath::Pi())*
343	TMath::Sqrt(-2TMath::Log(random[2j+1]));
344	}
345	}
346	SetTrack(fTrackIt,-1,part,p,origin,polar,0,kPPrimary,nt,fParentWeight);
347	break;
348	} // while(1)
349	} // Particle loop
350	// Header
351	AliGenEventHeader* header = new AliGenEventHeader("HIJINGparam");
352	// Event Vertex
353	header->SetPrimaryVertex(eventVertex);
354	gAlice->SetGenEventHeader(header);
355	}
356
357
358