1 #ifndef ALI_TPC_EXB_TWIST_H
2 #define ALI_TPC_EXB_TWIST_H
4 /* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
5 * See cxx source for full Copyright notice */
7 ////////////////////////////////////////////////////////////////////////////
9 // AliTPCExBTwist class //
10 // The class calculates the space point distortions due to a mismatch //
11 // of the E and B field axis (original code from STAR) //
12 // The class allows "effective Omega Tau" corrections. //
14 // date: 27/04/2010 //
15 // Authors: Jim Thomas, Magnus Mager, Stefan Rossegger //
16 ////////////////////////////////////////////////////////////////////////////
18 #include "AliTPCCorrection.h"
20 class AliTPCExBTwist : public AliTPCCorrection {
23 virtual ~AliTPCExBTwist();
25 // initialization and update functions
27 virtual void Update(const TTimeStamp &timeStamp);
30 // common setters and getters for ExB
31 virtual void SetOmegaTauT1T2(Float_t omegaTau,Float_t t1,Float_t t2) {
32 const Float_t wt1=t1*omegaTau;
34 const Float_t wt2=t2*omegaTau;
35 fC2=wt2*wt2/(1.+wt2*wt2);
37 void SetC1C2(Float_t c1,Float_t c2) {fC1=c1;fC2=c2;} // CAUTION: USE WITH CARE
38 Float_t GetC1() const {return fC1;}
39 Float_t GetC2() const {return fC2;}
41 // setters and getters for twist
42 void SetXTwist(Float_t xTwist) {fXTwist=xTwist;}
43 void SetYTwist(Float_t yTwist) {fYTwist=yTwist;}
44 Float_t GetXTwist() const {return fXTwist;}
45 Float_t GetYTwist() const {return fYTwist;}
47 virtual void Print(Option_t* option="") const;
50 virtual void GetCorrection(const Float_t x[],const Short_t roc,Float_t dx[]);
53 Float_t fC1; // coefficient C1 (compare Jim Thomas's notes for definitions)
54 Float_t fC2; // coefficient C2 (compare Jim Thomas's notes for definitions)
56 Float_t fXTwist; // Twist of E to B field in X-Z [rad]
57 Float_t fYTwist; // Twist of E to B field in Y-Z [rad]
59 ClassDef(AliTPCExBTwist,1);