9 #include "AliITStrack.h"
10 #include "AliGenerator.h"
15 AliITStrack::AliITStrack() {
16 //Origin A. Badala' and G.S. Pappalardo: e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
17 // default constructor
20 fmCovariance = new TMatrix(5,5);
21 flistCluster = new TObjArray;
26 fErrorVertex.ResizeTo(3);
28 ClusterInTrack = new TMatrix(6,9);
29 for(Int_t i=0; i<6; i++) (*ClusterInTrack)(i,6)=(*ClusterInTrack)(i,7)=
30 (*ClusterInTrack)(i,8)=-1.;
32 //alphaprov=-50.; //provvisorio
40 AliITStrack::AliITStrack(const AliITStrack &cobj) {
41 //Origin A. Badala' and G.S. Pappalardo: e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
44 fmCovariance = new TMatrix(5,5);
45 ClusterInTrack = new TMatrix(6,9);
46 for(Int_t i=0; i<6; i++) (*ClusterInTrack)(i,6)=(*ClusterInTrack)(i,7)=
47 (*ClusterInTrack)(i,8)=-1.;
48 flistCluster = new TObjArray;
50 fErrorVertex.ResizeTo(3);
51 fVertex = cobj.fVertex;
52 fErrorVertex = cobj.fErrorVertex;
55 fTPCtrack = cobj.fTPCtrack;
56 fNumClustInTrack = cobj.fNumClustInTrack;
58 fvTrack = cobj.fvTrack;
70 //alphaprov=cobj.alphaprov; //provvisorio
72 *fmCovariance = *cobj.fmCovariance;
74 *ClusterInTrack = *cobj.ClusterInTrack;
76 for(Int_t i=0; i<cobj.flistCluster->GetSize(); i++)
77 flistCluster->AddLast(cobj.flistCluster->At(i));
81 AliITStrack::AliITStrack(AliTPCtrack &obj)
83 //Origin A. Badala' and G.S. Pappalardo: e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
88 fErrorVertex.ResizeTo(3);
93 AliGenerator *gener = gAlice->Generator();
95 gener->GetOrigin(Vxg,Vyg,Vzg);
98 fVertex(0)=(Double_t)Vxg;
99 fVertex(1)=(Double_t)Vyg;
100 fVertex(2)=(Double_t)Vzg;
103 fmCovariance = new TMatrix(5,5);
104 ClusterInTrack = new TMatrix(6,9);
105 for(Int_t i=0; i<6; i++) (*ClusterInTrack)(i,6)=(*ClusterInTrack)(i,7)=
106 (*ClusterInTrack)(i,8)=-1.;
107 flistCluster = new TObjArray;
108 fNumClustInTrack = 0;
113 AliITStrack::~AliITStrack() {
117 if(fmCovariance) delete fmCovariance;
118 if(flistCluster) delete flistCluster;
119 if(ClusterInTrack) delete ClusterInTrack;
125 void AliITStrack::LmTPC() {
127 // Transform the TPC state vector from TPC-local to master and build a new state vector ITS-type
128 // The covariance matrix is also modified accordingly
129 //Origin A. Badala' and G.S. Pappalardo: e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
133 Double_t Alpha = fTPCtrack->GetAlpha();
135 //printf("LmTPC: Alpha %f\n",Alpha);
137 tpctrack(0) = fTPCtrack->GetY();
138 tpctrack(1) = fTPCtrack->GetZ();
139 tpctrack(2) = fTPCtrack->GetC();
140 tpctrack(3) = fTPCtrack->GetEta();
141 tpctrack(4) = fTPCtrack->GetTgl();
142 //cout<< " tpctracks = "<<tpctrack(0)<<" "<<tpctrack(1)<<" "<<tpctrack(2)<<" "<<tpctrack(3)<<" "<<tpctrack(4)<<
146 Double_t sina = TMath::Sin(Alpha);
147 Double_t cosa = TMath::Cos(Alpha);
148 Double_t xl= fTPCtrack->GetX();
149 xm = xl * cosa - tpctrack(0)*sina;
150 ym = xl * sina + tpctrack(0)*cosa;
152 //cout<<" xl e alpha = "<<xl<<" "<<Alpha<<"\n"; getchar();
156 ///////////////////////////////////// determine yo //////////////////////////////////////////////////
157 Double_t Vxl=fVertex(0)*cosa+fVertex(1)*sina;
158 Double_t Vyl= -fVertex(0)*sina+fVertex(1)*cosa;
159 Double_t Xo,Yo, signy;
160 Double_t R = 1./tpctrack(2);
161 Xo = tpctrack(3) / tpctrack(2);
163 Double_t Yo1, Yo2, diffsq1, diffsq2;
164 Yo1 = tpctrack(0) + TMath::Sqrt(R*R - (xl-Xo)*(xl-Xo));
165 Yo2 = tpctrack(0) - TMath::Sqrt(R*R - (xl-Xo)*(xl-Xo));
166 diffsq1=TMath::Abs((Yo1-Vyl)*(Yo1-Vyl)+(Xo-Vxl)*(Xo-Vxl)-R*R);
167 diffsq2=TMath::Abs((Yo2-Vyl)*(Yo2- Vyl)+(Xo-Vxl)*(Xo-Vxl)-R*R);
168 if(diffsq1<diffsq2) {Yo=Yo1; signy=1.;} else {Yo=Yo2; signy=-1.;};
169 ////////////////////////////////////////////////////////////////////////////////////////////////////
171 x0m = Xo * cosa - Yo * sina;
172 y0m = Xo * sina + Yo * cosa;
174 rtrack=TMath::Sqrt(xm*xm+ym*ym);
175 Double_t pigre=TMath::Pi();
177 if(ym == 0. || xm == 0.) {
178 if(ym == 0. && xm == 0.) {cout << " Error in AliITStrack::LmTPC x=0 and y=0 \n"; getchar();}
179 if(ym ==0. && xm>0.) phi=0.;
180 if(ym==0. && xm<0.) phi=pigre;
181 if(xm==0 && ym>0.) phi=pigre/2.;
182 if(xm==0 && ym<0.) phi=1.5*pigre;
185 if (xm>0. && ym>0.) phi=TMath::ATan(ym/xm);
186 if (xm<0. && ym>0.) phi=pigre+TMath::ATan(ym/xm);
187 if (xm<0. && ym<0.) phi=pigre+TMath::ATan(ym/xm);
188 if (xm>0. && ym<0.) phi=(2*pigre)+TMath::ATan(ym/xm);
190 if(phi<0. || phi>(2*pigre)) {cout<<"attention error on phi in AliITStrack:LmTPC \n"; getchar();}
194 fvTrack(3)=tpctrack(4);
195 fvTrack(4)=tpctrack(2);
198 alphaprov=pigre-PhiDef(x0m,y0m)-PhiDef(fVertex(0),fVertex(1));
199 if(alphaprov<0.) alphaprov=alphaprov+2.*pigre;
200 //cout<<" PhiDef(x0m,y0m) ="<<PhiDef(x0m,y0m)<<"\n";
201 //cout<<" PhiDef(fVertex(0),fVertex(1)) = "<<PhiDef(fVertex(0),fVertex(1))<<"\n";
202 //cout<<"alphaprov = "<<alphaprov<<"\n"; getchar();
203 //cout<<" fvTrack(0) prima = "<<fvTrack(0)<<"\n";
204 fvTrack(0)-=alphaprov;
205 if(fvTrack(0)<0.) fvTrack(0)+= 2.*pigre;
206 //cout<<" fvTrack(0) dopo = "<<fvTrack(0)<<" alphaprov = "<<alphaprov<<"\n";
207 cout<<" fvertex = "<<fVertex(0)<<" "<<fVertex(1)<<" "<<fVertex(2)<<"\n";
210 ///////////////////////////////////////////////////////////////////////////////////////////////////
213 Double_t dd=TMath::Sqrt((x0m-fVertex(0))*(x0m-fVertex(0))+(y0m-fVertex(1))*(y0m-fVertex(1)));
215 if (R>0) signdd=1.; else signdd=-1.;
216 fvTrack(2)=signdd*dd-R;
217 //cout<<" fvertex = "<<fVertex(0)<<" "<<fVertex(1)<<" "<<fVertex(2)<<"\n";
218 //cout<<" fvTrack(2) ="<<fvTrack(2)<<"\n"; getchar();
222 fTPCtrack->GetCovariance(cov);
228 localM(1,0)=localM(0,1)=cov[1];
229 localM(2,0)=localM(0,2)=cov[3];
230 localM(2,1)=localM(1,2)=cov[4];
231 localM(3,0)=localM(0,3)=cov[6];
232 localM(3,1)=localM(1,3)=cov[7];
233 localM(3,2)=localM(2,3)=cov[8];
234 localM(4,0)=localM(0,4)=cov[10];
235 localM(4,1)=localM(1,4)=cov[11];
236 localM(4,2)=localM(2,4)=cov[12];
237 localM(4,3)=localM(3,4)=cov[13];
241 Double_t dfidy, dDdy, dDdC, dDdeta;
243 dfidy=(xm*cosa+ym*sina)/(rtrack*rtrack);
244 dDdy=signdd*((y0m-fVertex(1))*cosa-(x0m-fVertex(0))*sina)/dd;
245 Double_t dyodr=signy*(R+(xl-Xo)*tpctrack(3))/TMath::Sqrt(R*R-(xl-Xo)*(xl-Xo));
246 Double_t dyomdr=sina*tpctrack(3)+cosa*dyodr;
247 Double_t dxomdr=cosa*tpctrack(3)-sina*dyodr;
248 Double_t ddddR=((x0m-fVertex(0))*dxomdr+(y0m-fVertex(1))*dyomdr)/dd;
249 dDdC=-R*R*(signdd*ddddR-1.);
250 Double_t dyoldxol=signy*(xl-Xo)/TMath::Sqrt(R*R-(xl-Xo)*(xl-Xo));
251 Double_t dxomdeta=R*(cosa-sina*dyoldxol);
252 Double_t dyomdeta=R*(sina+cosa*dyoldxol);
253 dDdeta=signdd*((x0m-fVertex(0))*dxomdeta+(y0m-fVertex(1))*dyomdeta)/dd;
255 F(0,1)=F(0,2)=F(0,3)=F(0,4)=0.;
257 F(1,0)=F(1,2)=F(1,3)=F(1,4)=0.;
262 F(3,0)=F(3,1)=F(3,2)=F(3,3)=0.;
264 F(4,0)=F(4,1)=F(4,3)=F(4,4)=0.;
266 // cout<<" Matrice F \n";
267 // F.Print(); getchar();
268 TMatrix Ft(TMatrix::kTransposed,F);
269 TMatrix temp(localM);
272 B*=temp; // B=F*localM*Ft
273 // cout<<" Matrice C\n";
274 // B.Print(); getchar();
279 AliITStrack &AliITStrack::operator=(AliITStrack obj) {
280 //Origin A. Badala' and G.S. Pappalardo: e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
284 delete ClusterInTrack;
285 fmCovariance = new TMatrix(5,5);
286 ClusterInTrack = new TMatrix(6,9);
287 flistCluster = new TObjArray;
289 fTPCtrack = obj.fTPCtrack;
291 fNumClustInTrack = obj.fNumClustInTrack;
294 fErrorVertex=obj.fErrorVertex;
295 fvTrack = obj.fvTrack;
305 //alphaprov=obj.alphaprov; //proviisorio
307 *fmCovariance = *obj.fmCovariance;
308 *ClusterInTrack = *obj.ClusterInTrack;
309 for(Int_t i=0; i<obj.flistCluster->GetSize(); i++) flistCluster->AddLast(obj.flistCluster->At(i));
315 void AliITStrack::PutCluster(Int_t layerc, TVector vecclust) {
316 //Origin A. Badala' and G.S. Pappalardo: e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
318 (*ClusterInTrack)(layerc,0) = vecclust(0);
319 (*ClusterInTrack)(layerc,1) = vecclust(1);
320 (*ClusterInTrack)(layerc,2) = vecclust(2);
321 (*ClusterInTrack)(layerc,3) = vecclust(3);
322 (*ClusterInTrack)(layerc,4) = vecclust(4);
323 (*ClusterInTrack)(layerc,5) = vecclust(5);
324 (*ClusterInTrack)(layerc,6) = vecclust(6);
325 (*ClusterInTrack)(layerc,7) = vecclust(7);
326 (*ClusterInTrack)(layerc,8) = vecclust(8);
331 void AliITStrack::GetClusters() {
333 TMatrix A(*ClusterInTrack);
335 for(Int_t i=0;i<6; i++){
336 B(i,0)=A(i,6); B(i,1)=A(i,7); B(i,2)=A(i,8);
344 TVector AliITStrack::GetLabTrack(Int_t lay) {
346 VecLabel(0)=( (Float_t) (*ClusterInTrack)(lay,6) );
347 VecLabel(1)=( (Float_t) (*ClusterInTrack)(lay,7) );
348 VecLabel(2)=( (Float_t) (*ClusterInTrack)(lay,8) );
352 void AliITStrack::Search(TVector VecTotLabref, Long_t &labref, Int_t &freq){
353 //Origin A. Badala' and G.S. Pappalardo: e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
358 for(Int_t i=0; i<18; i++) vecfreq[i]=0;
360 for(Int_t i=0; i<18; i++) {
361 for(Int_t j=0; j<18; j++) {
362 if(VecTotLabref(i) == 0.) VecTotLabref(i)=-3.;
363 if( (VecTotLabref(i)>=0.) && (VecTotLabref(i)==VecTotLabref(j)) ) vecfreq[i]++;
367 Long_t labdefault= (Long_t)1000000.;
369 for(Int_t i=0; i<18; i++) {
370 if(vecfreq[i]>freq) {freq=vecfreq[i]; imax=i;}
372 if(imax<0) labref=labdefault; else labref=(Long_t) VecTotLabref(imax);
376 void AliITStrack::Propagation(Double_t rk) {
377 //Origin A. Badala' and G.S. Pappalardo: e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
378 //Propagation of track
379 Double_t duepi=2.*TMath::Pi();
380 Double_t rkm1=rtrack;
381 //cout<<" rk e rkm1 dentro Propagation "<<rk<<" "<<rkm1<<"\n";
384 Double_t Ak=argA(rk), Akm1=argA(rkm1);
385 Double_t ak=arga(rk), akm1=arga(rkm1);
386 fvTrack(0)+=TMath::ASin(Ak)-TMath::ASin(Akm1);
387 if(fvTrack(0)>duepi) fvTrack(0)-=duepi;
388 if(fvTrack(0)<0.) fvTrack(0)+=duepi;
390 Double_t tgl=fvTrack(3);
391 Double_t C=fvTrack(4);
392 Double_t D=fvTrack(2);
394 fvTrack(1)+=tgl/Cy*(TMath::ASin(ak)-TMath::ASin(akm1));
396 //cout<<"fvTrack(0) fvTrack(1) e rtrack dentro Propagation = "<<fvTrack(0)<<" "<<fvTrack(1)<<" "<<rtrack<<"\n";
399 Double_t Bk=argB(rk), Bkm1=argB(rkm1);
400 Double_t Ck=argC(rk), Ckm1=argC(rkm1);
402 F(0,2)=Ck/TMath::Sqrt(1.-Ak*Ak) - Ckm1/TMath::Sqrt(1.-Akm1*Akm1);
403 F(0,4)=Bk/TMath::Sqrt(1.-Ak*Ak) - Bkm1/TMath::Sqrt(1.-Akm1*Akm1);
404 F(1,2)=tgl*D*(1./rk - 1./rkm1);
406 F(0,0)=F(1,1)=F(2,2)=F(3,3)=F(4,4)=1.;
408 TMatrix Ft(TMatrix::kTransposed,F);
409 TMatrix temp(*fmCovariance);
410 //cout<<" C Matrix prima propagation =\n";
411 //temp.Print(); getchar();
415 //cout<<" C Matrix dopo propagation =\n"; // B=F*C*Ft
416 //B.Print(); getchar();
420 void AliITStrack::AddEL(Double_t signdE, Bool_t flagtot, Double_t mass=0.1396) {
421 //Origin A. Badala' and G.S. Pappalardo: e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
425 s(0)=0.0026+0.00283; s(1)=0.018; s(2)=0.0094; s(3)=0.0095; s(4)=0.0091; s(5)=0.0087;
426 //0.00277 is added in the first layer to take into account the energy loss in the beam pipe
428 Double_t cl=1.+fvTrack(3)*fvTrack(3); // cl=1/(cosl)**2 = 1 + (tgl)**2
429 Double_t sqcl=TMath::Sqrt(cl);
432 Double_t p2=pt*pt*cl;
433 Double_t E=TMath::Sqrt(p2+mass*mass);
434 Double_t beta2=p2/(p2+mass*mass);
438 Double_t stot=s(0)+s(1)+s(2)+s(3)+s(4)+s(5);
439 dE=0.153/beta2*(log(5940*beta2/(1-beta2)) - beta2)*stot*21.82*sqcl;
441 dE=0.153/beta2*(log(5940*beta2/(1-beta2)) - beta2)*s(fLayer-1)*21.82*sqcl;
446 Double_t p=TMath::Sqrt(E*E-mass*mass);
448 if((fvTrack)(4) < 0.) sign=-1.;
450 Double_t CC=(0.3*0.2)/(pt*100.);
455 void AliITStrack::Correct(Double_t rk) {
456 //Origin A. Badala' and G.S. Pappalardo: e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
457 // correct track to take into account real geometry detector
459 Double_t duepi=2.*TMath::Pi();
460 Double_t rkm1=rtrack;
461 Double_t Ak=argA(rk), Akm1=argA(rkm1);
462 Double_t ak=arga(rk), akm1=arga(rkm1);
464 fvTrack(0)+=TMath::ASin(Ak)-TMath::ASin(Akm1);
465 if(fvTrack(0)>duepi) fvTrack(0)-=duepi;
466 if(fvTrack(0)<0.) fvTrack(0)+=duepi;
468 Double_t tgl=fvTrack(3);
469 Double_t C=fvTrack(4);
471 fvTrack(1)+=tgl/Cy*(TMath::ASin(ak)-TMath::ASin(akm1));
476 void AliITStrack::AddMS() {
478 ////////// Modification of the covariance matrix to take into account multiple scattering ///////////
479 //Origin A. Badala' and G.S. Pappalardo: e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
483 s(0)=0.0026+0.00283; s(1)=0.018; s(2)=0.0094; s(3)=0.0095; s(4)=0.0091; s(5)=0.0087;
484 //0.00277 is added in the first layer to take into account the energy loss in the beam pipe
485 Double_t mass=0.1396;
486 Int_t layer=(Int_t)GetLayer();
488 Double_t tgl=fvTrack(3);
489 Double_t cosl=TMath::Cos(TMath::ATan(tgl));
490 Double_t D=fvTrack(2);
491 Double_t C=fvTrack(4);
493 Double_t Q20=1./(cosl*cosl);
496 Double_t Q40=Cy*(rtrack*rtrack-D*D)/(1.+ 2.*Cy*D);
497 Double_t dd=D+Cy*D*D-Cy*rtrack*rtrack;
498 Double_t Q41=-1./cosl*TMath::Sqrt(rtrack*rtrack - dd*dd)/(1.+ 2.*Cy*D);
501 Double_t xk=rtrack*TMath::Cos(fvTrack(0));
502 Double_t yk=rtrack*TMath::Sin(fvTrack(0));
503 Double_t rvertex=TMath::Sqrt((xk-fVertex(0))*(xk-fVertex(0)) + (yk-fVertex(1))*(yk-fVertex(1)));
504 Double_t Q40=Cy*(rvertex*rvertex-D*D)/(1.+ 2.*Cy*D);
505 Double_t dd=D+Cy*D*D-Cy*rvertex*rvertex;
506 Double_t Q41=-1./cosl*TMath::Sqrt(rvertex*rvertex - dd*dd)/(1.+ 2.*Cy*D);
510 J(0,0)=0.; J(0,1)=0.;
511 J(1,0)=0.; J(1,1)=0.;
514 J(3,0)=Q20; J(3,1)=0.;
515 J(4,0)=Q30; J(4,1)=0.;
517 Double_t p2=(GetPt()*GetPt())/(cosl*cosl);
518 Double_t beta2=p2/(p2+mass*mass);
519 Double_t theta2=14.1*14.1/(beta2*p2*1.e6)*(s(layer-1)/cosl);
521 TMatrix Jt(TMatrix::kTransposed,J);
522 TMatrix Q(J,TMatrix::kMult,Jt);
529 void AliITStrack::PrimaryTrack() {
530 //Origin A. Badala' and G.S. Pappalardo: e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
531 // calculation of part of covariance matrix for vertex constraint
535 Rlayer[0]=4.; Rlayer[1]=7.; Rlayer[2]=14.9; Rlayer[3]=23.8;
536 Rlayer[4]=39.1; Rlayer[5]=43.6;
538 Double_t Cy=fvTrack(4)/2.;
539 Double_t tgl=(fvTrack(1)-Zv)*Cy/TMath::ASin(Cy*rtrack);
542 fvTrack(1)=rtrack*tgl;
547 newC(4,4)=(*fmCovariance)(4,4);
548 (*fmCovariance)=newC;
551 for (Int_t i=0; i<6; i++) {
552 Propagation(Rlayer[i]);
554 d2(i)=(*fmCovariance)(2,2);
555 tgl2(i)=(*fmCovariance)(3,3);
556 dtgl(i)=(*fmCovariance)(2,3);
563 Int_t AliITStrack::DoNotCross(Double_t rk) const{
564 Double_t C=fvTrack(4);
565 Double_t D=fvTrack(2);
567 return (TMath::Abs((Cy*rk+(1.+Cy*D)*D/rk)/(1.+2.*Cy*D))>=1.)?1:0;
571 Double_t AliITStrack::argA(Double_t rk) const {
572 Double_t C=fvTrack(4);
573 Double_t D=fvTrack(2);
575 Double_t arg=(Cy*rk + (1 + Cy*D)*D/rk)/(1.+ 2.*Cy*D);
576 if (TMath::Abs(arg) < 1.) return arg;
577 //cout<<"class AliITSTrack: argA out of range !\n";/* getchar();*/
578 return (arg>0) ? 1. : -1.;
581 Double_t AliITStrack::arga(Double_t rk) const {
582 Double_t C=fvTrack(4);
583 Double_t D=fvTrack(2);
585 Double_t arg=(rk*rk - D*D)/(1.+ 2.*Cy*D);
586 if (arg<0.) {/*cout<<"class AliITSTrack: arga out of range !\n";*/ arg=0.;}
587 return Cy*TMath::Sqrt(arg);
590 Double_t AliITStrack::argB(Double_t rk) const {
591 Double_t C=fvTrack(4);
592 Double_t D=fvTrack(2);
594 return (rk*rk - D*D)/(rk*(1.+ 2.*Cy*D)*(1.+ 2.*Cy*D));
597 Double_t AliITStrack::argC(Double_t rk) const {
598 Double_t C=fvTrack(4);
599 Double_t D=fvTrack(2);
601 return (1./rk - 2.*Cy*argA(rk)/(1.+ 2.*Cy*D));
604 Double_t AliITStrack::PhiDef(Double_t x, Double_t y){
605 Double_t pigre= TMath::Pi();
607 if(y == 0. || x == 0.) {
608 if(y == 0. && x == 0.) {
609 cout << " Error in AliITStracking::PhiDef x=0 and y=0 \n"; getchar();
611 if(y==0. && x>0.) phi=0.;
612 if(y==0. && x<0.) phi=pigre;
613 if(x==0 && y>0.) phi=pigre/2.;
614 if(x==0 && y<0.) phi=1.5*pigre;
617 if (x>0. && y>0.) phi=TMath::ATan(y/x);
618 if (x<0. && y>0.) phi=pigre+TMath::ATan(y/x);
619 if (x<0. && y<0.) phi=pigre+TMath::ATan(y/x);
620 if (x>0. && y<0.) phi=(2.*pigre)+TMath::ATan(y/x);
622 if(phi<0. || phi>(2*pigre)) {
623 cout<<" Error on phi in AliITStracking::PhiDef \n"; getchar();