X-Git-Url: http://git.uio.no/git/?a=blobdiff_plain;f=STEER%2FAliExternalTrackParam.h;h=0bc5d63ccb8c0e925952bfda5c49b23a25456e98;hb=8e5d5edff11954d3e70fbc1b007bf964626b24ab;hp=be4ce3201cd7ff1d3f919e6a4fe5f4570c9953d6;hpb=0e8460af4805c037ecf4375f3d7618470c7ebc9a;p=u%2Fmrichter%2FAliRoot.git

diff --git a/STEER/AliExternalTrackParam.h b/STEER/AliExternalTrackParam.h
index be4ce3201cd..0bc5d63ccb8 100644
--- a/STEER/AliExternalTrackParam.h
+++ b/STEER/AliExternalTrackParam.h
@@ -25,11 +25,15 @@
 const Double_t kVeryBig=1./kAlmost0;
 const Double_t kMostProbablePt=0.35;
 
-Double_t ApproximateBetheBloch(Double_t);
-
 class AliVVertex;
 class TPolyMarker3D; 
 
+const Double_t kC0max=100*100, // SigmaY<=100cm
+               kC2max=100*100, // SigmaZ<=100cm
+               kC5max=1*1,     // SigmaSin<=1
+               kC9max=1*1,     // SigmaTan<=1
+               kC14max=100*100; // Sigma1/Pt<=100 1/GeV
+
 class AliExternalTrackParam: public AliVTrack {
  public:
   AliExternalTrackParam();
@@ -42,8 +46,17 @@ class AliExternalTrackParam: public AliVTrack {
 			Double_t cv[21],Short_t sign);
   virtual ~AliExternalTrackParam(){}
 
-  void Set(Double_t x,Double_t alpha,
-			const Double_t param[5], const Double_t covar[15]);
+  template <typename T>
+  void Set(T x, T alpha, const T param[5], const T covar[15]) {
+    //  Sets the parameters
+    fX=x; fAlpha=alpha;
+    for (Int_t i = 0; i < 5; i++)  fP[i] = param[i];
+    for (Int_t i = 0; i < 15; i++) fC[i] = covar[i];
+
+    CheckCovariance();
+
+  }
+
   void Set(Double_t xyz[3],Double_t pxpypz[3],Double_t cv[21],Short_t sign);
 
   static void SetMostProbablePt(Double_t pt) { fgMostProbablePt=pt; }
@@ -83,14 +96,14 @@ class AliExternalTrackParam: public AliVTrack {
   // additional functions for AliVParticle
   Double_t Px() const;
   Double_t Py() const;
-  Double_t Pz() const;
+  Double_t Pz() const { return Pt()*GetTgl(); }
   Double_t Pt() const { return TMath::Abs(GetSignedPt()); }
   Double_t P() const { return GetP(); }
   Bool_t   PxPyPz(Double_t p[3]) const { return GetPxPyPz(p); }
   
   Double_t Xv() const;
   Double_t Yv() const;
-  Double_t Zv() const;
+  Double_t Zv() const {return GetZ();}
   Bool_t   XvYvZv(Double_t x[3]) const { return GetXYZ(x); }
 
   Double_t OneOverPt() const { return 1./Pt(); }
@@ -100,7 +113,7 @@ class AliExternalTrackParam: public AliVTrack {
   virtual Double_t M() const;
   Double_t Eta() const;
   virtual Double_t Y() const;
-  Short_t  Charge() const { return (Short_t)GetSign(); }
+  virtual Short_t  Charge() const { return (Short_t)GetSign(); }
   virtual const Double_t *PID() const { return 0x0; }
 
   // additional functions from AliVTrack
@@ -114,17 +127,42 @@ class AliExternalTrackParam: public AliVTrack {
     return (TMath::Abs(fP[4])>kAlmost0) ? 1./fP[4]:TMath::Sign(kVeryBig,fP[4]);
   }
   Double_t Get1P() const;
-  Double_t GetC(Double_t b) const {return fP[4]*b*kB2C;}
+  virtual Double_t GetC(Double_t b) const {return fP[4]*b*kB2C;}
   void GetDZ(Double_t x,Double_t y,Double_t z,Double_t b,Float_t dz[2]) const; 
   Double_t GetD(Double_t xv, Double_t yv, Double_t b) const; 
   Double_t GetLinearD(Double_t xv, Double_t yv) const; 
   Bool_t CorrectForMeanMaterial(Double_t xOverX0, Double_t xTimesRho, 
         Double_t mass,  Bool_t anglecorr=kFALSE,
-	Double_t (*f)(Double_t)=ApproximateBetheBloch);
+	Double_t (*f)(Double_t)=AliExternalTrackParam::BetheBlochSolid);
+
+  //
+  // Bethe-Bloch formula parameterizations
+  //
+  static Double_t BetheBlochAleph(Double_t bg,
+                                  Double_t kp1=0.76176e-1,
+                                  Double_t kp2=10.632,
+                                  Double_t kp3=0.13279e-4,
+                                  Double_t kp4=1.8631,
+                                  Double_t kp5=1.9479
+				  );
+  static Double_t BetheBlochGeant(Double_t bg,
+                                  Double_t kp0=2.33,
+                                  Double_t kp1=0.20,
+                                  Double_t kp2=3.00,
+                                  Double_t kp3=173e-9,
+                                  Double_t kp4=0.49848
+				  );
+    
+  static Double_t BetheBlochSolid(Double_t bg);
+  static Double_t BetheBlochGas(Double_t bg);
+
   Double_t GetPredictedChi2(Double_t p[2],Double_t cov[3]) const;
 
   Double_t 
     GetPredictedChi2(Double_t p[3],Double_t covyz[3],Double_t covxyz[3]) const;
+
+  Double_t GetPredictedChi2(const AliExternalTrackParam *t) const;
+
   Bool_t 
     PropagateTo(Double_t p[3],Double_t covyz[3],Double_t covxyz[3],Double_t b);
 
@@ -132,20 +170,22 @@ class AliExternalTrackParam: public AliVTrack {
   Bool_t Update(Double_t p[2],Double_t cov[3]);
   Bool_t Rotate(Double_t alpha);
   Bool_t PropagateTo(Double_t x, Double_t b);
-  Bool_t Propagate(Double_t alpha, Double_t x, Double_t b) {
-    if (Rotate(alpha))
-      if (PropagateTo(x,b)) return kTRUE;
-    return kFALSE;
-  }
+  Bool_t Propagate(Double_t alpha, Double_t x, Double_t b);
+  Bool_t PropagateBxByBz(Double_t alpha, Double_t x, Double_t b[3]);
   void   Propagate(Double_t len,Double_t x[3],Double_t p[3],Double_t bz) const;
   Bool_t Intersect(Double_t pnt[3], Double_t norm[3], Double_t bz) const;
 
+  static void g3helx3(Double_t qfield, Double_t step, Double_t vect[7]); 
+  Bool_t PropagateToBxByBz(Double_t x, const Double_t b[3]);
+
   void GetHelixParameters(Double_t h[6], Double_t b) const;
   Double_t GetDCA(const AliExternalTrackParam *p, Double_t b,
     Double_t &xthis,Double_t &xp) const;
   Double_t PropagateToDCA(AliExternalTrackParam *p, Double_t b);
   Bool_t PropagateToDCA(const AliVVertex *vtx, Double_t b, Double_t maxd,
                         Double_t dz[2]=0, Double_t cov[3]=0);
+  Bool_t PropagateToDCABxByBz(const AliVVertex *vtx, Double_t b[3], 
+         Double_t maxd, Double_t dz[2]=0, Double_t cov[3]=0);
   
   void GetDirection(Double_t d[3]) const;
   Bool_t GetPxPyPz(Double_t *p) const;
@@ -160,7 +200,7 @@ class AliExternalTrackParam: public AliVTrack {
 
   //Deprecated
   Bool_t CorrectForMaterial(Double_t d, Double_t x0, Double_t mass,
-			    Double_t (*f)(Double_t)=ApproximateBetheBloch);
+	 Double_t (*f)(Double_t)=AliExternalTrackParam::BetheBlochSolid);
 
   Bool_t GetDistance(AliExternalTrackParam *param2, Double_t x, Double_t dist[3], Double_t b);
   Int_t GetIndex(Int_t i, Int_t j) const;
@@ -170,7 +210,13 @@ class AliExternalTrackParam: public AliVTrack {
   //
   virtual void FillPolymarker(TPolyMarker3D *pol, Float_t magf, Float_t minR, Float_t maxR, Float_t stepR);
   virtual void DrawTrack(Float_t magF, Float_t minR, Float_t maxR, Float_t stepR);
- protected:
+
+  virtual Bool_t Translate(Double_t *vTrasl,Double_t *covV);
+
+  void CheckCovariance();
+
+/*  protected: */
+ private:
   Double_t &Par(Int_t i) {return fP[i];}
   Double_t &Cov(Int_t i) {return fC[i];}
   
@@ -189,11 +235,26 @@ inline void AliExternalTrackParam::ResetCovariance(Double_t s2) {
   //
   // Reset the covarince matrix to "something big"
   //
-    fC[0]*= s2;
-    fC[1] = 0.;  fC[2]*= s2;
-    fC[3] = 0.;  fC[4] = 0.;  fC[5]*= s2;
-    fC[6] = 0.;  fC[7] = 0.;  fC[8] = 0.;  fC[9]*= s2;
-    fC[10]= 0.;  fC[11]= 0.;  fC[12]= 0.;  fC[13]= 0.;  fC[14]*=s2;
+
+  s2 = TMath::Abs(s2);
+  Double_t fC0=fC[0]*s2,
+           fC2=fC[2]*s2,
+           fC5=fC[5]*s2,
+           fC9=fC[9]*s2,
+           fC14=fC[14]*s2;
+ 
+  if (fC0>kC0max)  fC0 = kC0max;
+  if (fC2>kC2max)  fC2 = kC2max;
+  if (fC5>kC5max)  fC5 = kC5max;
+  if (fC9>kC9max)  fC9 = kC9max;
+  if (fC14>kC14max)  fC14 = kC14max;
+
+
+    fC[0] = fC0;
+    fC[1] = 0.;  fC[2] = fC2;
+    fC[3] = 0.;  fC[4] = 0.;  fC[5] = fC5;
+    fC[6] = 0.;  fC[7] = 0.;  fC[8] = 0.;  fC[9] = fC9;
+    fC[10]= 0.;  fC[11]= 0.;  fC[12]= 0.;  fC[13]= 0.;  fC[14] = fC14;
 }