- Double_t x1=fX, x2=x1+(xk-x1), dx=x2-x1, y1=fY, z1=fZ;
- Double_t c1=fC*x1 - fE, r1=sqrt(1.- c1*c1);
- Double_t c2=fC*x2 - fE, r2=sqrt(1.- c2*c2);
-
- fY += dx*(c1+c2)/(r1+r2);
- fZ += dx*(c1+c2)/(c1*r2 + c2*r1)*fT;
-
- //f = F - 1
- Double_t rr=r1+r2, cc=c1+c2, xx=x1+x2;
- Double_t f02= dx*(rr*xx + cc*(c1*x1/r1+c2*x2/r2))/(rr*rr);
- Double_t f03=-dx*(2*rr + cc*(c1/r1 + c2/r2))/(rr*rr);
- Double_t cr=c1*r2+c2*r1;
- Double_t f12= dx*fT*(cr*xx-cc*(r1*x2-c2*c1*x1/r1+r2*x1-c1*c2*x2/r2))/(cr*cr);
- Double_t f13=-dx*fT*(2*cr + cc*(c2*c1/r1-r1 + c1*c2/r2-r2))/(cr*cr);
- Double_t f14= dx*cc/cr;
-
- //b = C*ft
- Double_t b00=f02*fCcy + f03*fCey, b01=f12*fCcy + f13*fCey + f14*fCty;
- Double_t b10=f02*fCcz + f03*fCez, b11=f12*fCcz + f13*fCez + f14*fCtz;
- Double_t b20=f02*fCcc + f03*fCec, b21=f12*fCcc + f13*fCec + f14*fCtc;
- Double_t b30=f02*fCec + f03*fCee, b31=f12*fCec + f13*fCee + f14*fCte;
- Double_t b40=f02*fCtc + f03*fCte, b41=f12*fCtc + f13*fCte + f14*fCtt;
-
- //a = f*b = f*C*ft
- Double_t a00=f02*b20+f03*b30,a01=f02*b21+f03*b31,a11=f12*b21+f13*b31+f14*b41;
-
- //F*C*Ft = C + (a + b + bt)
- fCyy += a00 + 2*b00;
- fCzy += a01 + b01 + b10;
- fCcy += b20;
- fCey += b30;
- fCty += b40;
- fCzz += a11 + 2*b11;
- fCcz += b21;
- fCez += b31;
- fCtz += b41;
-
- fX=x2;
-
- //Multiple scattering******************
- Double_t d=sqrt((x1-fX)*(x1-fX)+(y1-fY)*(y1-fY)+(z1-fZ)*(z1-fZ));
- Double_t p2=GetPt()*GetPt()*(1.+fT*fT);
- Double_t beta2=p2/(p2 + pm*pm);
-
- Double_t ey=fC*fX - fE, ez=fT;
- Double_t xz=fC*ez, zz1=ez*ez+1, xy=fE+ey;
-
- Double_t theta2=14.1*14.1/(beta2*p2*1e6)*d/x0*rho;
- fCcc += xz*xz*theta2;
- fCec += xz*ez*xy*theta2;
- fCtc += xz*zz1*theta2;
- fCee += (2*ey*ez*ez*fE+1-ey*ey+ez*ez+fE*fE*ez*ez)*theta2;
- fCte += ez*zz1*xy*theta2;
- fCtt += zz1*zz1*theta2;
-
- //Energy losses************************
- Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2)*d*rho;
- if (x1 < x2) dE=-dE;
- cc=fC;
- fC*=(1.- sqrt(p2+pm*pm)/p2*dE);
- fE+=fX*(fC-cc);
-
- return 1;
+ Double_t bz=GetBz();
+ if (!AliExternalTrackParam::PropagateTo(xk,bz)) return kFALSE;
+
+ Double_t d = TMath::Sqrt((GetX()-oldX)*(GetX()-oldX) +
+ (GetY()-oldY)*(GetY()-oldY) +
+ (GetZ()-oldZ)*(GetZ()-oldZ));
+ if (IsStartedTimeIntegral() && GetX()>oldX) AddTimeStep(d);
+
+ if (oldX < xk) d = -d;
+ if (!AliExternalTrackParam::CorrectForMaterial(d*rho/x0,x0,GetMass()))
+ return kFALSE;
+
+ return kTRUE;