[u/mrichter/AliRoot.git] / TPC / AliTPCExBBShape.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.                  *
 **************************************************************************/

////////////////////////////////////////////////////////////////////////////
//                                                                        //
// AliExBBShape class                                                     //
// The class calculates the space point distortions due to the B field    //
// shape imperfections using a second order technique based on integrals  //
// over Bz (e.g. int By/Bz) obtained via the AliMagF class                //
// The class allows "effective Omega Tau" corrections.                    //
//                                                                        //
// date: 27/04/2010                                                       //
// Authors: Magnus Mager, Jim Thomas, Stefan Rossegger                    //
//                                                                        //
// Example usage:                                                         //
//  AliMagF mag("mag","mag");                                             //
//  AliTPCExBBShape exb;                                                  //
//  exb.SetBField(&mag);             // use Bfield from AliMagF           //
//  exb.SetOmegaTauT1T2(0.32,1.,1.); // values ideally from OCDB          //
//  // plot dRPhi distortions ...                                         //
//  exb.CreateHistoDRPhiinZR(0,100,100)->Draw("surf2");                   //
////////////////////////////////////////////////////////////////////////////

#include <AliMagF.h>
#include "TGeoGlobalMagField.h"
#include "AliTPCcalibDB.h"
#include "AliTPCParam.h"
#include "AliLog.h"

#include "AliTPCExBBShape.h"

AliTPCExBBShape::AliTPCExBBShape()
  : AliTPCCorrection("exb_bshape","ExB B-shape"),
    fC1(0.),fC2(0.),
    fBField(0)
{
  //
  // default constructor
  //
}

AliTPCExBBShape::~AliTPCExBBShape() {
  //
  // virtual destructor
  //
}

void AliTPCExBBShape::Init() {
  //
  // Initialization funtion
  //
  
  AliMagF* magF= (AliMagF*)TGeoGlobalMagField::Instance()->GetField();
  if (!magF) AliError("Magneticd field - not initialized");
  Double_t bzField = magF->SolenoidField()/10.; //field in T
  SetBField(magF);
  AliTPCParam *param= AliTPCcalibDB::Instance()->GetParameters();
  if (!param) AliError("Parameters - not initialized");
  Double_t vdrift = param->GetDriftV()/1000000.; // [cm/us]   // From dataBase: to be updated: per second (ideally)
  Double_t ezField = 400; // [V/cm]   // to be updated: never (hopefully)
  Double_t wt = -10.0 * (bzField*10) * vdrift / ezField ; 
  // Correction Terms for effective omegaTau; obtained by a laser calibration run
  SetOmegaTauT1T2(wt,fT1,fT2);


}

void AliTPCExBBShape::Update(const TTimeStamp &/*timeStamp*/) {
  //
  // Update function 
  //
  AliMagF* magF= (AliMagF*)TGeoGlobalMagField::Instance()->GetField();
  if (!magF) AliError("Magneticd field - not initialized");
  Double_t bzField = magF->SolenoidField()/10.; //field in T
  SetBField(magF);
  AliTPCParam *param= AliTPCcalibDB::Instance()->GetParameters();
  if (!param) AliError("Parameters - not initialized");
  Double_t vdrift = param->GetDriftV()/1000000.; // [cm/us]   // From dataBase: to be updated: per second (ideally)
  Double_t ezField = 400; // [V/cm]   // to be updated: never (hopefully)
  Double_t wt = -10.0 * (bzField*10) * vdrift / ezField ; 
  // Correction Terms for effective omegaTau; obtained by a laser calibration run
  SetOmegaTauT1T2(wt,fT1,fT2);


}


void AliTPCExBBShape::GetCorrection(const Float_t x[],const Short_t roc,Float_t dx[]) {
  //
  // Calculates the space point corrections of the B field inperfections (B field shape) 
  //

  if (!fBField) {
    for (Int_t j=0;j<3;++j) dx[j]=0.;
    return;
  }

  const Double_t xStart[3]={ x[0], x[1], x[2] };
  const Double_t xEnd[3]={ x[0],  x[1],  roc%36<18?fgkTPCZ0:-fgkTPCZ0 };

  Double_t intBStart[3];
  Double_t intBEnd[3];

  fBField->GetTPCRatInt(xStart,intBStart);
  fBField->GetTPCRatInt(xEnd,  intBEnd  );

  const Float_t intBxOverBz=(intBEnd[0]-intBStart[0]);
  const Float_t intByOverBz=(intBEnd[1]-intBStart[1]);
  
  dx[0]=fC2*intBxOverBz-fC1*intByOverBz;
  dx[1]=fC1*intBxOverBz+fC2*intByOverBz;
  dx[2]=0.;


}

void AliTPCExBBShape::GetBxAndByOverBz(const Float_t x[],const Short_t roc,Float_t BxByOverBz[]) {
  //
  // This function is purely for calibration purposes
  // Returns the via AliMagF obtaind B field integrals  
  // 

  if (!fBField) {
    for (Int_t j=0;j<3;++j) BxByOverBz[j]=0.;
    return;
  }

  const Double_t xStart[3]={ x[0], x[1], x[2] };
  const Double_t xEnd[3]={ x[0],  x[1],  roc%36<18?fgkTPCZ0:-fgkTPCZ0 };

  Double_t intBStart[3];
  Double_t intBEnd[3];

  fBField->GetTPCRatInt(xStart,intBStart);
  fBField->GetTPCRatInt(xEnd,  intBEnd  );

  const Float_t intBxOverBz=(intBEnd[0]-intBStart[0]);
  const Float_t intByOverBz=(intBEnd[1]-intBStart[1]);
  
  BxByOverBz[0]=intBxOverBz;
  BxByOverBz[1]=intByOverBz;

}

void AliTPCExBBShape::Print(Option_t* option) const {
  //
  // Print function to check the settings (e.g. voltage offsets)
  // option=="a" prints details of the B field settings and the 
  // C0 and C1 coefficents (for calibration purposes)
  //
  TString opt = option; opt.ToLower();
  printf("%s\t%s\n - B field settings:\n",GetTitle(),GetName());
  fBField->Print(option);
  //  printf(" - B field: X-Twist: %1.5lf rad, Y-Twist: %1.5lf rad \n",fBField->Print(option));
  if (opt.Contains("a")) { // Print all details  
    printf(" - T1: %1.4f, T2: %1.4f \n",fT1,fT2);
    printf(" - C1: %1.4f, C2: %1.4f \n",fC1,fC2);
  }    
}
Commit	Line	Data
0116859c	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	// //
	18	// AliExBBShape class //
	19	// The class calculates the space point distortions due to the B field //
	20	// shape imperfections using a second order technique based on integrals //
	21	// over Bz (e.g. int By/Bz) obtained via the AliMagF class //
	22	// The class allows "effective Omega Tau" corrections. //
	23	// //
	24	// date: 27/04/2010 //
	25	// Authors: Magnus Mager, Jim Thomas, Stefan Rossegger //
	26	// //
	27	// Example usage: //
	28	// AliMagF mag("mag","mag"); //
	29	// AliTPCExBBShape exb; //
	30	// exb.SetBField(&mag); // use Bfield from AliMagF //
	31	// exb.SetOmegaTauT1T2(0.32,1.,1.); // values ideally from OCDB //
	32	// // plot dRPhi distortions ... //
	33	// exb.CreateHistoDRPhiinZR(0,100,100)->Draw("surf2"); //
	34	////////////////////////////////////////////////////////////////////////////
	35
	36	#include <AliMagF.h>
534fd34a	37	#include "TGeoGlobalMagField.h"
	38	#include "AliTPCcalibDB.h"
	39	#include "AliTPCParam.h"
	40	#include "AliLog.h"
0116859c	41
	42	#include "AliTPCExBBShape.h"
	43
	44	AliTPCExBBShape::AliTPCExBBShape()
	45	: AliTPCCorrection("exb_bshape","ExB B-shape"),
	46	fC1(0.),fC2(0.),
	47	fBField(0)
	48	{
	49	//
	50	// default constructor
	51	//
	52	}
	53
	54	AliTPCExBBShape::~AliTPCExBBShape() {
	55	//
	56	// virtual destructor
	57	//
	58	}
	59
e527a1b9	60	void AliTPCExBBShape::Init() {
e527a1b9	61	//
534fd34a	62	// Initialization funtion
e527a1b9	63	//
e527a1b9	64
534fd34a	65	AliMagF* magF= (AliMagF*)TGeoGlobalMagField::Instance()->GetField();
	66	if (!magF) AliError("Magneticd field - not initialized");
	67	Double_t bzField = magF->SolenoidField()/10.; //field in T
	68	SetBField(magF);
	69	AliTPCParam *param= AliTPCcalibDB::Instance()->GetParameters();
	70	if (!param) AliError("Parameters - not initialized");
	71	Double_t vdrift = param->GetDriftV()/1000000.; // [cm/us] // From dataBase: to be updated: per second (ideally)
e527a1b9	72	Double_t ezField = 400; // [V/cm] // to be updated: never (hopefully)
e527a1b9	73	Double_t wt = -10.0 * (bzField10) vdrift / ezField ;
e527a1b9	74	// Correction Terms for effective omegaTau; obtained by a laser calibration run
534fd34a	75	SetOmegaTauT1T2(wt,fT1,fT2);
e527a1b9	76
	77
	78	}
	79
	80	void AliTPCExBBShape::Update(const TTimeStamp &/timeStamp/) {
	81	//
	82	// Update function
	83	//
534fd34a	84	AliMagF* magF= (AliMagF*)TGeoGlobalMagField::Instance()->GetField();
	85	if (!magF) AliError("Magneticd field - not initialized");
	86	Double_t bzField = magF->SolenoidField()/10.; //field in T
	87	SetBField(magF);
	88	AliTPCParam *param= AliTPCcalibDB::Instance()->GetParameters();
	89	if (!param) AliError("Parameters - not initialized");
	90	Double_t vdrift = param->GetDriftV()/1000000.; // [cm/us] // From dataBase: to be updated: per second (ideally)
e527a1b9	91	Double_t ezField = 400; // [V/cm] // to be updated: never (hopefully)
e527a1b9	92	Double_t wt = -10.0 * (bzField10) vdrift / ezField ;
e527a1b9	93	// Correction Terms for effective omegaTau; obtained by a laser calibration run
534fd34a	94	SetOmegaTauT1T2(wt,fT1,fT2);
e527a1b9	95
	96
	97	}
	98
	99
	100
0116859c	101	void AliTPCExBBShape::GetCorrection(const Float_t x[],const Short_t roc,Float_t dx[]) {
	102	//
	103	// Calculates the space point corrections of the B field inperfections (B field shape)
	104	//
	105
	106	if (!fBField) {
	107	for (Int_t j=0;j<3;++j) dx[j]=0.;
	108	return;
	109	}
	110
	111	const Double_t xStart[3]={ x[0], x[1], x[2] };
b1f0a2a5	112	const Double_t xEnd[3]={ x[0], x[1], roc%36<18?fgkTPCZ0:-fgkTPCZ0 };
0116859c	113
	114	Double_t intBStart[3];
	115	Double_t intBEnd[3];
	116
	117	fBField->GetTPCRatInt(xStart,intBStart);
	118	fBField->GetTPCRatInt(xEnd, intBEnd );
	119
	120	const Float_t intBxOverBz=(intBEnd[0]-intBStart[0]);
	121	const Float_t intByOverBz=(intBEnd[1]-intBStart[1]);
	122
	123	dx[0]=fC2intBxOverBz-fC1intByOverBz;
	124	dx[1]=fC1intBxOverBz+fC2intByOverBz;
	125	dx[2]=0.;
	126
	127
	128	}
	129
	130	void AliTPCExBBShape::GetBxAndByOverBz(const Float_t x[],const Short_t roc,Float_t BxByOverBz[]) {
	131	//
	132	// This function is purely for calibration purposes
	133	// Returns the via AliMagF obtaind B field integrals
	134	//
	135
	136	if (!fBField) {
	137	for (Int_t j=0;j<3;++j) BxByOverBz[j]=0.;
	138	return;
	139	}
	140
	141	const Double_t xStart[3]={ x[0], x[1], x[2] };
b1f0a2a5	142	const Double_t xEnd[3]={ x[0], x[1], roc%36<18?fgkTPCZ0:-fgkTPCZ0 };
0116859c	143
	144	Double_t intBStart[3];
	145	Double_t intBEnd[3];
	146
	147	fBField->GetTPCRatInt(xStart,intBStart);
	148	fBField->GetTPCRatInt(xEnd, intBEnd );
	149
	150	const Float_t intBxOverBz=(intBEnd[0]-intBStart[0]);
	151	const Float_t intByOverBz=(intBEnd[1]-intBStart[1]);
	152
	153	BxByOverBz[0]=intBxOverBz;
	154	BxByOverBz[1]=intByOverBz;
	155
	156	}
	157
	158	void AliTPCExBBShape::Print(Option_t* option) const {
	159	//
	160	// Print function to check the settings (e.g. voltage offsets)
	161	// option=="a" prints details of the B field settings and the
	162	// C0 and C1 coefficents (for calibration purposes)
	163	//
	164	TString opt = option; opt.ToLower();
534fd34a	165	printf("%s\t%s\n - B field settings:\n",GetTitle(),GetName());
0116859c	166	fBField->Print(option);
0116859c	167	// printf(" - B field: X-Twist: %1.5lf rad, Y-Twist: %1.5lf rad \n",fBField->Print(option));
534fd34a	168	if (opt.Contains("a")) { // Print all details
534fd34a	169	printf(" - T1: %1.4f, T2: %1.4f \n",fT1,fT2);
0116859c	170	printf(" - C1: %1.4f, C2: %1.4f \n",fC1,fC2);
0116859c	171	}
0116859c	172	}