/**************************************************************************
* 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. *
**************************************************************************/
/* $Id$ */
//
///////////////////////////////////////////////////////////////////////////////
// //
// Time Projection Chamber version 3 -- detailed TPC and slow simulation //
//
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// //
// //
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#include
#include
#include
#include
#include
#include
#include
#include
#include "AliConst.h"
#include "AliRun.h"
#include "AliTPCDigitsArray.h"
#include "AliTPCParam.h"
#include "AliTPCParamSR.h"
#include "AliTPCTrackHitsV2.h"
#include "AliTPCv3.h"
#include "AliMC.h"
#include "TGeoManager.h"
#include "TGeoVolume.h"
#include "TGeoPcon.h"
#include "TGeoTube.h"
#include "TGeoPgon.h"
#include "TGeoTrd1.h"
#include "TGeoCompositeShape.h"
#include "TGeoPara.h"
ClassImp(AliTPCv3)
//_____________________________________________________________________________
AliTPCv3::AliTPCv3():AliTPC(),fIdSens(0)
{
fHitType = 1;
}
//_____________________________________________________________________________
AliTPCv3::AliTPCv3(const char *name, const char *title) :
AliTPC(name, title), fIdSens(0)
{
//
// Standard constructor for Time Projection Chamber version 3
//
SetBufferSize(128000);
if (fTPCParam)
fTPCParam->Write(fTPCParam->GetTitle());
fHitType =1;
}
//_____________________________________________________________________________
void AliTPCv3::CreateGeometry()
{
//
// Creation of the TPC coarse geometry (version 3)
// The whole drift volume is sensitive
// Origin Marek Kowalski Cracow
//
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//----------------------------------------------------------
// This geometry is written using TGeo class
// Firstly the shapes are defined, and only then the volumes
// What is recognized by the MC are volumes
//----------------------------------------------------------
//
// tpc - this will be the mother volume
//
//
// here I define a volume TPC
// retrive the medium name with "TPC_" as a leading string
//
TGeoPcon *tpc = new TGeoPcon(0.,360.,18); //18 sections
tpc->DefineSection(0,-290.,77.,278.);
tpc->DefineSection(1,-259.6,70.,278.);
//
tpc->DefineSection(2,-259.6,68.1,278.);
tpc->DefineSection(3,-253.6,68.1,278.);
//
tpc->DefineSection(4,-253.6,68.,278.);
tpc->DefineSection(5,-74.0,60.8,278.);
//
tpc->DefineSection(6,-74.0,60.1,278.);
tpc->DefineSection(7,-73.3,60.1,278.);
//
tpc->DefineSection(8,-73.3,56.9,278.);
tpc->DefineSection(9,73.3,56.9,278.);
//
tpc->DefineSection(10,73.3,60.1,278.);
tpc->DefineSection(11,74.0,60.1,278.);
//
tpc->DefineSection(12,74.0,60.8,278.);
tpc->DefineSection(13,253.6,65.5,278.);
//
tpc->DefineSection(14,253.6,65.6,278.);
tpc->DefineSection(15,259.6,65.6,278.);
//
tpc->DefineSection(16,259.6,70.0,278.);
tpc->DefineSection(17,290.,77.,278.);
//
TGeoMedium *m1 = gGeoManager->GetMedium("TPC_Air");
TGeoVolume *v1 = new TGeoVolume("TPC_M",tpc,m1);
//
// drift volume - sensitive volume, extended beyond the
// endcaps, because of the alignment
//
TGeoPcon *dvol = new TGeoPcon(0.,360.,6);
dvol->DefineSection(0,-260.,74.5,264.4);
dvol->DefineSection(1,-253.6,74.5,264.4);
//
dvol->DefineSection(2,-253.6,76.6774,258.);
dvol->DefineSection(3,253.6,76.6774,258.);
//
dvol->DefineSection(4,253.6,74.5,264.4);
dvol->DefineSection(5,260.,74.5,264.4);
//
TGeoMedium *m5 = gGeoManager->GetMedium("TPC_Ne-CO2-N-2");
TGeoVolume *v9 = new TGeoVolume("TPC_Drift",dvol,m5);
//
v1->AddNode(v9,1);
//
// outer insulator
//
TGeoPcon *tpco = new TGeoPcon(0.,360.,6); //insulator
//
tpco->DefineSection(0,-256.6,264.8,278.);
tpco->DefineSection(1,-253.6,264.8,278.);
//
tpco->DefineSection(2,-253.6,258.,278.);
tpco->DefineSection(3,250.6,258.,278.);
//
tpco->DefineSection(4,250.6,258.,275.5);
tpco->DefineSection(5,253.6,258.,275.5);
//
TGeoMedium *m2 = gGeoManager->GetMedium("TPC_CO2");
TGeoVolume *v2 = new TGeoVolume("TPC_OI",tpco,m2);
//
// outer containment vessel
//
TGeoPcon *tocv = new TGeoPcon(0.,360.,6); // containment vessel
//
tocv->DefineSection(0,-256.6,264.8,278.);
tocv->DefineSection(1,-253.6,264.8,278.);
//
tocv->DefineSection(2,-253.6,274.8124,278.);
tocv->DefineSection(3,247.6,274.8124,278.);
//
tocv->DefineSection(4,247.6,270.4,278.);
tocv->DefineSection(5,250.6,270.4,278.);
//
TGeoMedium *m3 = gGeoManager->GetMedium("TPC_Al");
TGeoVolume *v3 = new TGeoVolume("TPC_OCV",tocv,m3);
//
TGeoTube *to1 = new TGeoTube(274.8174,277.995,252.1); //epoxy
TGeoTube *to2 = new TGeoTube(274.8274,277.985,252.1); //tedlar
TGeoTube *to3 = new TGeoTube(274.8312,277.9812,252.1);//prepreg2
TGeoTube *to4 = new TGeoTube(274.9062,277.9062,252.1);//nomex
//
TGeoMedium *sm1 = gGeoManager->GetMedium("TPC_Epoxy");
TGeoMedium *sm2 = gGeoManager->GetMedium("TPC_Tedlar");
TGeoMedium *sm3 = gGeoManager->GetMedium("TPC_Prepreg2");
TGeoMedium *sm4 = gGeoManager->GetMedium("TPC_Nomex");
//
TGeoVolume *tov1 = new TGeoVolume("TPC_OCV1",to1,sm1);
TGeoVolume *tov2 = new TGeoVolume("TPC_OCV2",to2,sm2);
TGeoVolume *tov3 = new TGeoVolume("TPC_OCV3",to3,sm3);
TGeoVolume *tov4 = new TGeoVolume("TPC_OCV4",to4,sm4);
//-------------------------------------------------------
// Tpc Outer Field Cage
// daughters - composite (sandwich)
//-------------------------------------------------------
TGeoPcon *tofc = new TGeoPcon(0.,360.,6);
//
tofc->DefineSection(0,-253.6,258.,269.6);
tofc->DefineSection(1,-250.6,258.,269.6);
//
tofc->DefineSection(2,-250.6,258.,260.0676);
tofc->DefineSection(3,250.6,258.,260.0676);
//
tofc->DefineSection(4,250.6,258.,275.5);
tofc->DefineSection(5,253.6,258.,275.5);
//
TGeoVolume *v4 = new TGeoVolume("TPC_TOFC",tofc,m3);
//sandwich
TGeoTube *tf1 = new TGeoTube(258.0,260.0676,252.1); //tedlar
TGeoTube *tf2 = new TGeoTube(258.0038,260.0638,252.1); //prepreg3
TGeoTube *tf3 = new TGeoTube(258.0338,260.0338,252.1);//nomex
//
TGeoMedium *sm5 = gGeoManager->GetMedium("TPC_Prepreg3");
//
TGeoVolume *tf1v = new TGeoVolume("TPC_OFC1",tf1,sm2);
TGeoVolume *tf2v = new TGeoVolume("TPC_OFC2",tf2,sm5);
TGeoVolume *tf3v = new TGeoVolume("TPC_OFC3",tf3,sm4);
//
// outer part - positioning
//
tov1->AddNode(tov2,1); tov2->AddNode(tov3,1); tov3->AddNode(tov4,1);
//
tf1v->AddNode(tf2v,1); tf2v->AddNode(tf3v,1);
//
v3->AddNode(tov1,1,new TGeoTranslation(0.,0.,-1.5)); v4->AddNode(tf1v,1);
//
v2->AddNode(v3,1); v2->AddNode(v4,1);
//
v1->AddNode(v2,1);
//-----------------------------------------------------------
//--------------------------------------------------------------------
// Tpc Inner INsulator (CO2)
// the cones, the central drum and the inner f.c. sandwich with a piece
// of the flane will be placed in the TPC
//--------------------------------------------------------------------
TGeoPcon *tpci = new TGeoPcon(0.,360.,4);
//
tpci->DefineSection(0,-253.6,68.4,76.6774);
tpci->DefineSection(1,-74.0,61.2,76.6774);
//
tpci->DefineSection(2,74.0,61.2,76.6774);
//
tpci->DefineSection(3,253.6,65.9,76.6774);
//
TGeoVolume *v5 = new TGeoVolume("TPC_INI",tpci,m2);
//
// now the inner field cage - only part of flanges (2 copies)
//
TGeoTube *tif1 = new TGeoTube(69.9,76.6774,1.5);
TGeoVolume *v6 = new TGeoVolume("TPC_IFC1",tif1,m3);
//
//---------------------------------------------------------
// Tpc Inner Containment vessel - Muon side
//---------------------------------------------------------
TGeoPcon *tcms = new TGeoPcon(0.,360.,10);
//
tcms->DefineSection(0,-259.1,68.1,74.2);
tcms->DefineSection(1,-253.6,68.1,74.2);
//
tcms->DefineSection(2,-253.6,68.1,68.4);
tcms->DefineSection(3,-74.0,60.9,61.2);
//
tcms->DefineSection(4,-74.0,60.1,61.2);
tcms->DefineSection(5,-73.3,60.1,61.2);
//
tcms->DefineSection(6,-73.3,56.9,61.2);
tcms->DefineSection(7,-73.0,56.9,61.2);
//
tcms->DefineSection(8,-73.0,56.9,58.8);
tcms->DefineSection(9,-71.3,56.9,58.8);
//
TGeoVolume *v7 = new TGeoVolume("TPC_ICVM",tcms,m3);
//-----------------------------------------------
// inner containment vessel - shaft side
//-----------------------------------------------
TGeoPcon *tcss = new TGeoPcon(0.,360.,10);
//
tcss->DefineSection(0,71.3,56.9,58.8);
tcss->DefineSection(1,73.0,56.9,58.8);
//
tcss->DefineSection(2,73.0,56.9,61.2);
tcss->DefineSection(3,73.3,56.9,61.2);
//
tcss->DefineSection(4,73.3,60.1,61.2);
tcss->DefineSection(5,74.0,60.1,61.2);
//
tcss->DefineSection(6,74.0,60.9,61.2);
tcss->DefineSection(7,253.6,65.6,65.9);
//
tcss->DefineSection(8,253.6,65.6,74.2);
tcss->DefineSection(9,258.1,65.6,74.2);
//
TGeoVolume *v8 = new TGeoVolume("TPC_ICVS",tcss,m3);
//-----------------------------------------------
// Inner field cage
// define 4 parts and make an assembly
//-----------------------------------------------
// part1 - Al - 2 copies
TGeoTube *t1 = new TGeoTube(76.6774,78.845,0.75);
TGeoVolume *tv1 = new TGeoVolume("TPC_IFC2",t1,m3);
// sandwich - outermost parts - 2 copies
TGeoTube *t2 = new TGeoTube(76.6774,78.845,74.175); // tedlar 38 microns
TGeoTube *t3 = new TGeoTube(76.6812,78.8412,74.175); // prepreg2 500 microns
TGeoTube *t4 = new TGeoTube(76.7312,78.7912,74.175); // prepreg3 300 microns
TGeoTube *t5 = new TGeoTube(76.7612,78.7612,74.175); // nomex 2 cm
//
TGeoVolume *tv2 = new TGeoVolume("TPC_IFC3",t2,sm2);
TGeoVolume *tv3 = new TGeoVolume("TPC_IFC4",t3,sm3);
TGeoVolume *tv4 = new TGeoVolume("TPC_IFC5",t4,sm5);
TGeoVolume *tv5 = new TGeoVolume("TPC_IFC6",t5,sm4);
//
// middle parts - 2 copies
TGeoTube *t6 = new TGeoTube(76.6774,78.795,5.); // tedlar 38 microns
TGeoTube *t7 = new TGeoTube(76.6812,78.7912,5.); // prepreg2 250 microns
TGeoTube *t8 = new TGeoTube(76.7062,78.7662,5.); // prepreg3 300 microns
TGeoTube *t9 = new TGeoTube(76.7362,78.7362,5.); // nomex 2 cm
//
TGeoVolume *tv6 = new TGeoVolume("TPC_IFC7",t6,sm2);
TGeoVolume *tv7 = new TGeoVolume("TPC_IFC8",t7,sm3);
TGeoVolume *tv8 = new TGeoVolume("TPC_IFC9",t8,sm5);
TGeoVolume *tv9 = new TGeoVolume("TPC_IFC10",t9,sm4);
// central part - 1 copy
TGeoTube *t10 = new TGeoTube(76.6774,78.745,93.75); // tedlar 38 microns
TGeoTube *t11 = new TGeoTube(76.6812,78.7412,93.75); // prepreg3 300 microns
TGeoTube *t12 = new TGeoTube(76.7112,78.7112,93.75); // nomex 2 cm
//
TGeoVolume *tv10 = new TGeoVolume("TPC_IFC11",t10,sm2);
TGeoVolume *tv11 = new TGeoVolume("TPC_IFC12",t11,sm5);
TGeoVolume *tv12 = new TGeoVolume("TPC_IFC13",t12,sm4);
//
// inner part - positioning
//
// creating a sandwich
tv2->AddNode(tv3,1); tv3->AddNode(tv4,1); tv4->AddNode(tv5,1);
//
tv6->AddNode(tv7,1); tv7->AddNode(tv8,1); tv8->AddNode(tv9,1);
//
tv10->AddNode(tv11,1); tv11->AddNode(tv12,1);
//
TGeoVolumeAssembly *tv100 = new TGeoVolumeAssembly("TPC_IFC");
//
tv100->AddNode(tv10,1);
tv100->AddNode(tv6,1,new TGeoTranslation(0.,0.,-98.75));
tv100->AddNode(tv6,2,new TGeoTranslation(0.,0.,98.75));
tv100->AddNode(tv2,1,new TGeoTranslation(0.,0.,-177.925));
tv100->AddNode(tv2,2,new TGeoTranslation(0.,0.,177.925));
tv100->AddNode(tv1,1,new TGeoTranslation(0.,0.,-252.85));
tv100->AddNode(tv1,2,new TGeoTranslation(0.,0.,252.85));
//
v5->AddNode(v6,1, new TGeoTranslation(0.,0.,-252.1));
v5->AddNode(v6,2, new TGeoTranslation(0.,0.,252.1));
v1->AddNode(v5,1); v1->AddNode(v7,1); v1->AddNode(v8,1);
v9->AddNode(tv100,1);
//
// central drum
//
// flange + sandwich
//
TGeoPcon *cfl = new TGeoPcon(0.,360.,6);
cfl->DefineSection(0,-71.1,59.7,61.2);
cfl->DefineSection(1,-68.6,59.7,61.2);
//
cfl->DefineSection(2,-68.6,60.6324,61.2);
cfl->DefineSection(3,68.6,60.6324,61.2);
//
cfl->DefineSection(4,68.6,59.7,61.2);
cfl->DefineSection(5,71.1,59.7,61.2);
//
TGeoVolume *cflv = new TGeoVolume("TPC_CDR",cfl,m3);
// sandwich
TGeoTube *cd1 = new TGeoTube(60.6424,61.19,71.1);
TGeoTube *cd2 = new TGeoTube(60.6462,61.1862,71.1);
TGeoTube *cd3 = new TGeoTube(60.6662,61.1662,71.1);
//
TGeoMedium *sm6 = gGeoManager->GetMedium("TPC_Prepreg1");
TGeoVolume *cd1v = new TGeoVolume("TPC_CDR1",cd1,sm2); //tedlar
TGeoVolume *cd2v = new TGeoVolume("TPC_CDR2",cd2,sm6);// prepreg1
TGeoVolume *cd3v = new TGeoVolume("TPC_CDR3",cd3,sm4); //nomex
//
// seals for central drum 2 copies
//
TGeoTube *cs = new TGeoTube(56.9,61.2,0.1);
TGeoMedium *sm7 = gGeoManager->GetMedium("TPC_Mylar");
TGeoVolume *csv = new TGeoVolume("TPC_CDRS",cs,sm7);
v1->AddNode(csv,1,new TGeoTranslation(0.,0.,-71.));
v1->AddNode(csv,2,new TGeoTranslation(0.,0.,71.));
//
// seal collars
TGeoPcon *se = new TGeoPcon(0.,360.,6);
se->DefineSection(0,-72.8,59.7,61.2);
se->DefineSection(1,-72.3,59.7,61.2);
//
se->DefineSection(2,-72.3,58.85,61.2);
se->DefineSection(3,-71.6,58.85,61.2);
//
se->DefineSection(4,-71.6,59.7,61.2);
se->DefineSection(5,-71.3,59.7,61.2);
//
TGeoVolume *sev = new TGeoVolume("TPC_CDCE",se,m3);
//
TGeoTube *si = new TGeoTube(56.9,58.8,1.);
TGeoVolume *siv = new TGeoVolume("TPC_CDCI",si,m3);
//
// define reflection matrix
//
TGeoRotation *ref = new TGeoRotation("ref",90.,0.,90.,90.,180.,0.);
//
cd1v->AddNode(cd2v,1); cd2v->AddNode(cd3v,1); cflv->AddNode(cd1v,1);
//
v1->AddNode(siv,1,new TGeoTranslation(0.,0.,-69.9));
v1->AddNode(siv,2,new TGeoTranslation(0.,0.,69.9));
v1->AddNode(sev,1); v1->AddNode(sev,2,ref); v1->AddNode(cflv,1);
//
// central membrane - 2 rings and a mylar membrane - assembly
//
TGeoTube *ih = new TGeoTube(81.05,84.05,0.3);
TGeoTube *oh = new TGeoTube(250.,256.,.5);
TGeoTube *mem = new TGeoTube(84.05,250,0.01);
TGeoVolume *ihv = new TGeoVolume("TPC_IHVH",ih,m3);
TGeoVolume *ohv = new TGeoVolume("TPC_OHVH",oh,m3);
TGeoVolume *memv = new TGeoVolume("TPC_HV",mem,sm7);
//
TGeoVolumeAssembly *cm = new TGeoVolumeAssembly("TPC_HVMEM");
cm->AddNode(ihv,1);
cm->AddNode(ohv,1);
cm->AddNode(memv,1);
v9->AddNode(cm,1);
//
// end caps - they are make as an assembly of single segments
// containing both readout chambers
//
Double_t openingAngle = 10.*TMath::DegToRad();
Double_t thick=1.5; // rib
Double_t shift = thick/TMath::Sin(openingAngle);
//
Double_t lowEdge = 86.3; // hole in the wheel
Double_t upEdge = 240.4; // hole in the wheel
//
new TGeoTubeSeg("sec",74.5,264.4,3.,0.,20.);
//
TGeoPgon *hole = new TGeoPgon("hole",0.,20.,1,4);
//
hole->DefineSection(0,-3.5,lowEdge-shift,upEdge-shift);
hole->DefineSection(1,-1.5,lowEdge-shift,upEdge-shift);
//
hole->DefineSection(2,-1.5,lowEdge-shift,upEdge+3.-shift);
hole->DefineSection(3,3.5,lowEdge-shift,upEdge+3.-shift);
//
Double_t ys = shift*TMath::Sin(openingAngle);
Double_t xs = shift*TMath::Cos(openingAngle);
TGeoTranslation *tr = new TGeoTranslation("tr",xs,ys,0.);
tr->RegisterYourself();
TGeoCompositeShape *chamber = new TGeoCompositeShape("sec-hole:tr");
TGeoVolume *sv = new TGeoVolume("TPC_WSEG",chamber,m3);
TGeoPgon *bar = new TGeoPgon("bar",0.,20.,1,2);
bar->DefineSection(0,-3.,131.5-shift,136.5-shift);
bar->DefineSection(1,1.5,131.5-shift,136.5-shift);
TGeoVolume *barv = new TGeoVolume("TPC_WBAR",bar,m3);
TGeoVolumeAssembly *ch = new TGeoVolumeAssembly("TPC_WCH");//empty segment
//
ch->AddNode(sv,1); ch->AddNode(barv,1,tr);
//
// readout chambers
//
// IROC first
//
TGeoTrd1 *ibody = new TGeoTrd1(13.8742,21.3328,4.29,21.15);
TGeoVolume *ibdv = new TGeoVolume("TPC_IROCB",ibody,m3);
// empty space
TGeoTrd1 *emp = new TGeoTrd1(12.3742,19.8328,3.99,19.65);
TGeoVolume *empv = new TGeoVolume("TPC_IROCE",emp,m1);
ibdv->AddNode(empv,1,new TGeoTranslation(0.,-0.3,0.));
//bars
Double_t tga = (19.8328-12.3742)/39.3;
Double_t xmin,xmax;
xmin = 9.55*tga+12.3742;
xmax = 9.95*tga+12.3742;
TGeoTrd1 *ib1 = new TGeoTrd1(xmin,xmax,3.29,0.2);
TGeoVolume *ib1v = new TGeoVolume("TPC_IRB1",ib1,m3);
empv->AddNode(ib1v,1,new TGeoTranslation("tt1",0.,0.7,-9.9));
xmin=19.4*tga+12.3742;
xmax=19.9*tga+12.3742;
TGeoTrd1 *ib2 = new TGeoTrd1(xmin,xmax,3.29,0.25);
TGeoVolume *ib2v = new TGeoVolume("TPC_TRB2",ib2,m3);
empv->AddNode(ib2v,1,new TGeoTranslation(0.,0.7,0.));
xmin=29.35*tga+12.3742;
xmax=29.75*tga+12.3742;
TGeoTrd1 *ib3 = new TGeoTrd1(xmin,xmax,3.29,0.2);
TGeoVolume *ib3v = new TGeoVolume("TPC_IRB3",ib3,m3);
empv->AddNode(ib3v,1,new TGeoTranslation(0.,0.7,9.9));
//
// holes for connectors
//
TGeoBBox *conn = new TGeoBBox(0.4,0.3,4.675); // identical for iroc and oroc
TGeoVolume *connv = new TGeoVolume("TPC_RCCON",conn,m1);
TString fileName(gSystem->Getenv("ALICE_ROOT"));
fileName += "/TPC/conn_iroc.dat";
ifstream in;
in.open(fileName.Data(), ios_base::in); // asci file
for(Int_t i =0;i<86;i++){
Double_t y = 3.99;
Double_t x,z,ang;
in>>x>>z>>ang;
z-=26.5;
TGeoRotation *rrr = new TGeoRotation();
rrr->RotateY(ang);
TGeoCombiTrans *trans = new TGeoCombiTrans("trans",x,y,z,rrr);
ibdv->AddNode(connv,i+1,trans);
}
in.close();
// "cap"
new TGeoTrd1("icap",14.5974,23.3521,1.19,24.825);
// "hole"
new TGeoTrd1("ihole",13.8742,21.3328,1.2,21.15);
TGeoTranslation *tr1 = new TGeoTranslation("tr1",0.,0.,1.725);
tr1->RegisterYourself();
TGeoCompositeShape *ic = new TGeoCompositeShape("icap-ihole:tr1");
TGeoVolume *icv = new TGeoVolume("TPC_IRCAP",ic,m3);
//
// pad plane and wire fixations
//
TGeoTrd1 *pp = new TGeoTrd1(14.5974,23.3521,0.3,24.825); //pad+iso
TGeoMedium *m4 = gGeoManager->GetMedium("TPC_G10");
TGeoVolume *ppv = new TGeoVolume("TPC_IRPP",pp,m4);
TGeoPara *f1 = new TGeoPara(.6,.5,24.825,0.,-10.,0.);
TGeoVolume *f1v = new TGeoVolume("TPC_IRF1",f1,m4);
TGeoPara *f2 = new TGeoPara(.6,.5,24.825,0.,10.,0.);
TGeoVolume *f2v = new TGeoVolume("TPC_IRF2",f2,m4);
//
TGeoVolumeAssembly *iroc = new TGeoVolumeAssembly("TPC_IROC");
//
iroc->AddNode(ibdv,1);
iroc->AddNode(icv,1,new TGeoTranslation(0.,3.1,-1.725));
iroc->AddNode(ppv,1,new TGeoTranslation(0.,4.59,-1.725));
tga =(23.3521-14.5974)/49.65;
Double_t xx = 24.825*tga+14.5974-0.6;
iroc->AddNode(f1v,1,new TGeoTranslation(-xx,5.39,-1.725));
iroc->AddNode(f2v,1,new TGeoTranslation(xx,5.39,-1.725));
//
// OROC
//
TGeoTrd1 *obody = new TGeoTrd1(22.2938,40.5084,4.19,51.65);
TGeoVolume *obdv = new TGeoVolume("TPC_OROCB",obody,m3);
TGeoTrd1 *oemp = new TGeoTrd1(20.2938,38.5084,3.89,49.65);
TGeoVolume *oempv = new TGeoVolume("TPC_OROCE",oemp,m1);
obdv->AddNode(oempv,1,new TGeoTranslation(0.,-0.3,0.));
//horizontal bars
tga=(38.5084-20.2938)/99.3;
xmin=tga*10.2+20.2938;
xmax=tga*10.6+20.2938;
TGeoTrd1 *ob1 = new TGeoTrd1(xmin,xmax,2.915,0.2);
TGeoVolume *ob1v = new TGeoVolume("TPC_ORB1",ob1,m3);
//
xmin=22.55*tga+20.2938;
xmax=24.15*tga+20.2938;
TGeoTrd1 *ob2 = new TGeoTrd1(xmin,xmax,2.915,0.8);
TGeoVolume *ob2v = new TGeoVolume("TPC_ORB2",ob2,m3);
//
xmin=36.1*tga+20.2938;
xmax=36.5*tga+20.2938;
TGeoTrd1 *ob3 = new TGeoTrd1(xmin,xmax,2.915,0.2);
TGeoVolume *ob3v = new TGeoVolume("TPC_ORB3",ob3,m3);
//
xmin=49.0*tga+20.2938;
xmax=50.6*tga+20.2938;
TGeoTrd1 *ob4 = new TGeoTrd1(xmin,xmax,2.915,0.8);
TGeoVolume *ob4v = new TGeoVolume("TPC_ORB4",ob4,m3);
//
xmin=63.6*tga+20.2938;
xmax=64.0*tga+20.2938;
TGeoTrd1 *ob5 = new TGeoTrd1(xmin,xmax,2.915,0.2);
TGeoVolume *ob5v = new TGeoVolume("TPC_ORB5",ob5,m3);
//
xmin=75.5*tga+20.2938;
xmax=77.15*tga+20.2938;
TGeoTrd1 *ob6 = new TGeoTrd1(xmin,xmax,2.915,0.8);
TGeoVolume *ob6v = new TGeoVolume("TPC_ORB6",ob6,m3);
//
xmin=88.7*tga+20.2938;
xmax=89.1*tga+20.2938;
TGeoTrd1 *ob7 = new TGeoTrd1(xmin,xmax,2.915,0.2);
TGeoVolume *ob7v = new TGeoVolume("TPC_ORB7",ob7,m3);
//
oempv->AddNode(ob1v,1,new TGeoTranslation(0.,0.975,-39.25));
oempv->AddNode(ob2v,1,new TGeoTranslation(0.,0.975,-26.3));
oempv->AddNode(ob3v,1,new TGeoTranslation(0.,0.975,-13.35));
oempv->AddNode(ob4v,1,new TGeoTranslation(0.,0.975,0.15));
oempv->AddNode(ob5v,1,new TGeoTranslation(0.,0.975,14.15));
oempv->AddNode(ob6v,1,new TGeoTranslation(0.,0.975,26.7));
oempv->AddNode(ob7v,1,new TGeoTranslation(0.,0.975,39.25));
// vertical bars
TGeoBBox *ob8 = new TGeoBBox(0.8,2.915,5.1);
TGeoBBox *ob9 = new TGeoBBox(0.8,2.915,5.975);
TGeoBBox *ob10 = new TGeoBBox(0.8,2.915,5.775);
TGeoBBox *ob11 = new TGeoBBox(0.8,2.915,6.25);
TGeoBBox *ob12 = new TGeoBBox(0.8,2.915,6.5);
//
TGeoVolume *ob8v = new TGeoVolume("TPC_ORB8",ob8,m3);
TGeoVolume *ob9v = new TGeoVolume("TPC_ORB9",ob9,m3);
TGeoVolume *ob10v = new TGeoVolume("TPC_ORB10",ob10,m3);
TGeoVolume *ob11v = new TGeoVolume("TPC_ORB11",ob11,m3);
TGeoVolume *ob12v = new TGeoVolume("TPC_ORB12",ob12,m3);
//
oempv->AddNode(ob8v,1,new TGeoTranslation(0.,0.975,-44.55));
oempv->AddNode(ob8v,2,new TGeoTranslation(0.,0.975,44.55));
oempv->AddNode(ob9v,1,new TGeoTranslation(0.,0.975,-33.075));
oempv->AddNode(ob9v,2,new TGeoTranslation(0.,0.975,-19.525));
oempv->AddNode(ob10v,1,new TGeoTranslation(0.,0.975,20.125));
oempv->AddNode(ob10v,2,new TGeoTranslation(0.,0.975,33.275));
oempv->AddNode(ob11v,1,new TGeoTranslation(0.,0.975,-6.9));
oempv->AddNode(ob12v,1,new TGeoTranslation(0.,0.975,7.45));
//
// holes for connectors
//
fileName = gSystem->Getenv("ALICE_ROOT");
fileName += "/TPC/conn_oroc.dat";
in.open(fileName.Data(), ios_base::in); // asci file
for(Int_t i =0;i<78;i++){
Double_t y =3.89;
Double_t x,z,ang;
Double_t x1,z1,x2,z2;
in>>x>>z>>ang;
Double_t xr = 4.7*TMath::Sin(ang*TMath::DegToRad());
Double_t zr = 4.7*TMath::Cos(ang*TMath::DegToRad());
//
x1=xr+x; x2=-xr+x; z1=zr+z; z2 = -zr+z;
//
TGeoRotation *rr = new TGeoRotation();
rr->RotateY(ang);
z1-=54.95;
z2-=54.95;
TGeoCombiTrans *trans1 = new TGeoCombiTrans("trans1",x1,y,z1,rr);
TGeoCombiTrans *trans2 = new TGeoCombiTrans("trans2",x2,y,z2,rr);
obdv->AddNode(connv,i+1,trans1);
obdv->AddNode(connv,i+79,trans2);
}
in.close();
// cap
new TGeoTrd1("ocap",23.3874,43.5239,1.09,57.1);
new TGeoTrd1("ohole",22.2938,40.5084,1.09,51.65);
TGeoTranslation *tr5 = new TGeoTranslation("tr5",0.,0.,-2.15);
tr5->RegisterYourself();
TGeoCompositeShape *oc = new TGeoCompositeShape("ocap-ohole:tr5");
TGeoVolume *ocv = new TGeoVolume("TPC_ORCAP",oc,m3);
//
// pad plane and wire fixations
//
TGeoTrd1 *opp = new TGeoTrd1(23.3874,43.5239,0.3,57.1);
TGeoVolume *oppv = new TGeoVolume("TPC_ORPP",opp,m4);
//
tga=(43.5239-23.3874)/114.2;
TGeoPara *f3 = new TGeoPara(.7,.6,57.1,0.,-10.,0.);
TGeoPara *f4 = new TGeoPara(.7,.6,57.1,0.,10.,0.);
xx = 57.1*tga+23.3874-0.7;
TGeoVolume *f3v = new TGeoVolume("TPC_ORF1",f3,m4);
TGeoVolume *f4v = new TGeoVolume("TPC_ORF2",f4,m4);
//
TGeoVolumeAssembly *oroc = new TGeoVolumeAssembly("TPC_OROC");
//
oroc->AddNode(obdv,1);
oroc->AddNode(ocv,1,new TGeoTranslation(0.,3.1,2.15));
oroc->AddNode(oppv,1,new TGeoTranslation(0.,4.49,2.15));
oroc->AddNode(f3v,1,new TGeoTranslation(-xx,5.39,2.15));
oroc->AddNode(f4v,1,new TGeoTranslation(xx,5.39,2.15));
//
// now iroc and oroc are placed into a sector...
//
TGeoVolumeAssembly *secta = new TGeoVolumeAssembly("TPC_SECT"); // a-side
TGeoVolumeAssembly *sectc = new TGeoVolumeAssembly("TPC_SECT"); // c-side
TGeoRotation rot1("rot1",90.,90.,0.);
TGeoRotation rot2("rot2");
rot2.RotateY(10.);
TGeoRotation *rot = new TGeoRotation("rot");
*rot=rot1*rot2;
//
Double_t x0,y0;
x0=110.2*TMath::Cos(openingAngle);
y0=110.2*TMath::Sin(openingAngle);
TGeoCombiTrans *combi1a = new TGeoCombiTrans("combi1",x0,y0,1.09+0.195,rot); //a-side
TGeoCombiTrans *combi1c = new TGeoCombiTrans("combi1",x0,y0,1.09+0.222,rot); //c-side
x0=188.45*TMath::Cos(openingAngle);
y0=188.45*TMath::Sin(openingAngle);
TGeoCombiTrans *combi2a = new TGeoCombiTrans("combi2",x0,y0,0.99+0.195,rot); //a-side
TGeoCombiTrans *combi2c = new TGeoCombiTrans("combi2",x0,y0,0.99+0.222,rot); //c-side
//
// A-side
//
secta->AddNode(ch,1);
secta->AddNode(iroc,1,combi1a);
secta->AddNode(oroc,1,combi2a);
//
// C-side
//
sectc->AddNode(ch,1);
sectc->AddNode(iroc,1,combi1c);
sectc->AddNode(oroc,1,combi2c);
//
// now I try to make wheels...
//
TGeoVolumeAssembly *wheela = new TGeoVolumeAssembly("TPC_ENDCAP");
TGeoVolumeAssembly *wheelc = new TGeoVolumeAssembly("TPC_ENDCAP");
//
for(Int_t i =0;i<18;i++){
Double_t phi = (20.*i);
TGeoRotation *r = new TGeoRotation();
r->RotateZ(phi);
wheela->AddNode(secta,i+1,r);
wheelc->AddNode(sectc,i+1,r);
}
// wheels in the drift volume!
TGeoCombiTrans *combi3 = new TGeoCombiTrans("combi3",0.,0.,256.6,ref);
v9->AddNode(wheela,1,combi3);
v9->AddNode(wheelc,2,new TGeoTranslation(0.,0.,-256.6));
//_____________________________________________________________
// service support wheel
//_____________________________________________________________
TGeoPgon *sw = new TGeoPgon(0.,20.,1,2);
sw->DefineSection(0,-4.,80.5,251.75);
sw->DefineSection(1,4.,80.5,251.75);
TGeoVolume *swv = new TGeoVolume("TPC_SWSEG",sw,m3); //Al
//
thick=1.;
shift = thick/TMath::Sin(openingAngle);
TGeoPgon *sh = new TGeoPgon(0.,20.,1,2);
sh->DefineSection(0,-4.,81.5-shift,250.75-shift);
sh->DefineSection(1,4.,81.5-shift,250.75-shift);
TGeoVolume *shv = new TGeoVolume("TPC_SWS1",sh,m1); //Air
//
TGeoMedium *m9 = gGeoManager->GetMedium("TPC_Si");
TGeoPgon *el = new TGeoPgon(0.,20.,1,2);
el->DefineSection(0,-1.872,81.5-shift,250.75-shift);
el->DefineSection(1,1.872,81.5-shift,250.75-shift);
TGeoVolume *elv = new TGeoVolume("TPC_ELEC",el,m9); //Si
//
shv->AddNode(elv,1);
//
ys = shift*TMath::Sin(openingAngle);
xs = shift*TMath::Cos(openingAngle);
swv->AddNode(shv,1,new TGeoTranslation(xs,ys,0.));
// cover
TGeoPgon *co = new TGeoPgon(0.,20.,1,2);
co->DefineSection(0,-0.5,77.,255.25);
co->DefineSection(1,0.5,77.,255.25);
TGeoVolume *cov = new TGeoVolume("TPC_SWC1",co,m3);//Al
// hole in a cover
TGeoPgon *coh = new TGeoPgon(0.,20.,1,2);
shift=4./TMath::Sin(openingAngle);
coh->DefineSection(0,-0.5,85.-shift,247.25-shift);
coh->DefineSection(1,0.5,85.-shift,247.25-shift);
//
TGeoVolume *cohv = new TGeoVolume("TPC_SWC2",coh,m1);
//
ys = shift*TMath::Sin(openingAngle);
xs = shift*TMath::Cos(openingAngle);
cov->AddNode(cohv,1,new TGeoTranslation(xs,ys,0.));
//
// Sector as an Assembly
//
TGeoVolumeAssembly *swhs = new TGeoVolumeAssembly("TPC_SSWSEC");
swhs->AddNode(swv,1);
swhs->AddNode(cov,1,new TGeoTranslation(0.,0.,-4.5));
swhs->AddNode(cov,2,new TGeoTranslation(0.,0.,4.5));
//
// SSW as an Assembly of sectors
//
TGeoVolumeAssembly *swheel = new TGeoVolumeAssembly("TPC_SSWHEEL");
for(Int_t i =0;i<18;i++){
Double_t phi = (20.*i);
TGeoRotation *r = new TGeoRotation();
r->RotateZ(phi);
swheel->AddNode(swhs,i+1,r);
}
v1->AddNode(swheel,1,new TGeoTranslation(0.,0.,-284.6));
v1->AddNode(swheel,2,new TGeoTranslation(0.,0.,284.6));
//
//----------------------------------------------------------
// TPc Support Rods - MAKROLON
//----------------------------------------------------------
TGeoMedium *m6=gGeoManager->GetMedium("TPC_Makrolon");
TGeoMedium *m7=gGeoManager->GetMedium("TPC_Cu");
// upper and lower rods differ in length!
Double_t *upar;
upar=NULL;
gGeoManager->Volume("TPC_Rod","TUBE",m6->GetId(),upar);
upar=new Double_t [3];
upar[0]=1.8;
upar[1]=2.2;
//
//HV rods - makrolon + 0.58cm (diameter) Cu
TGeoTube *hvr = new TGeoTube(0.,2.2,126.64);
TGeoTube *hvc = new TGeoTube(0.,0.29,126.64);
//
TGeoVolume *hvrv = new TGeoVolume("TPC_HV_Rod",hvr,m6);
TGeoVolume *hvcv = new TGeoVolume("TPC_HV_Cable",hvc,m7);
hvrv->AddNode(hvcv,1);
for(Int_t i=0;i<18;i++){
Double_t angle,x,y;
Double_t z,r;
angle=TMath::DegToRad()*20.*(Double_t)i;
r=81.5;
x=r * TMath::Cos(angle);
y=r * TMath::Sin(angle);
upar[2]=126.64; //lower
z= 126.96;
if(i==15){
v9->AddNode(hvrv,1,new TGeoTranslation(x,y,z));
v9->AddNode(hvrv,2,new TGeoTranslation(x,y,-z));
}
else{
gGeoManager->Node("TPC_Rod",i+1,"TPC_Drift",x,y,z,0,kTRUE,upar,3);//shaft
gGeoManager->Node("TPC_Rod",i+18,"TPC_Drift",x,y,-z,0,kTRUE,upar,3);//muon
}
r=254.25;
x=r * TMath::Cos(angle);
y=r * TMath::Sin(angle);
upar[2]=126.54; //upper
z=127.06;
gGeoManager->Node("TPC_Rod",i+36,"TPC_Drift",x,y,z,0,kTRUE,upar,3);
gGeoManager->Node("TPC_Rod",i+54,"TPC_Drift",x,y,-z,0,kTRUE,upar,3);
}
TGeoVolume *alice = gGeoManager->GetVolume("ALIC");
alice->AddNode(v1,1);
} // end of function
//_____________________________________________________________________________
void AliTPCv3::DrawDetector()
{
//
// Draw a shaded view of the Time Projection Chamber version 3
//
// Set everything unseen
gMC->Gsatt("*", "seen", -1);
//
// Set ALIC mother transparent
gMC->Gsatt("ALIC","SEEN",0);
//
// Set the volumes visible
//
gMC->Gsatt("TPC ","SEEN",0);
gMC->Gsatt("TOIN","SEEN",1);
gMC->Gsatt("TOIN","COLO",7);
gMC->Gsatt("TOCV","SEEN",1);
gMC->Gsatt("TOCV","COLO",4);
gMC->Gsatt("TSA1","SEEN",0);
gMC->Gsatt("TSA2","SEEN",0);
gMC->Gsatt("TSA3","SEEN",0);
gMC->Gsatt("TSA4","SEEN",0);
gMC->Gsatt("TSA5","SEEN",0);
gMC->Gsatt("TOFC","SEEN",1);
gMC->Gsatt("TOFC","COLO",4);
gMC->Gsatt("TSA6","SEEN",0);
gMC->Gsatt("TSA7","SEEN",0);
gMC->Gsatt("TSA8","SEEN",0);
gMC->Gsatt("TIIN","SEEN",1);
gMC->Gsatt("TIIN","COLO",7);
gMC->Gsatt("TII1","SEEN",0);
gMC->Gsatt("TIFC","SEEN",1);
gMC->Gsatt("TIFC","COLO",4);
gMC->Gsatt("TSA9","SEEN",0);
gMC->Gsatt("TS10","SEEN",0);
gMC->Gsatt("TS11","SEEN",0);
gMC->Gsatt("TS12","SEEN",0);
gMC->Gsatt("TS13","SEEN",0);
gMC->Gsatt("TS14","SEEN",0);
gMC->Gsatt("TICC","SEEN",0);
gMC->Gsatt("TICM","SEEN",0);
gMC->Gsatt("TS15","SEEN",0);
gMC->Gsatt("TS16","SEEN",0);
gMC->Gsatt("TS17","SEEN",0);
gMC->Gsatt("TS18","SEEN",0);
gMC->Gsatt("TS19","SEEN",0);
gMC->Gsatt("TPJ1","SEEN",0);
gMC->Gsatt("TPJ2","SEEN",0);
gMC->Gsatt("TICS","SEEN",0);
gMC->Gsatt("TDGS","SEEN",0);
gMC->Gsatt("TIRC","SEEN",0);
gMC->Gsatt("TIC1","SEEN",1);
gMC->Gsatt("TIPP","SEEN",0);
gMC->Gsatt("TIC3","SEEN",0);
gMC->Gsatt("TRCE","SEEN",0);
gMC->Gsatt("TPSC","SEEN",0);
gMC->Gsatt("TPCC","SEEN",0);
gMC->Gsatt("TORC","SEEN",0);
gMC->Gsatt("TOPP","SEEN",0);
gMC->Gsatt("TOC3","SEEN",0);
gMC->Gsatt("TOC1","SEEN",1);
gMC->Gsatt("TSSW","SEEN",1);
gMC->Gsatt("TSWC","SEEN",1);
gMC->Gsatt("TSSW","COLO",3);
gMC->Gsatt("TSWC","COLO",3);
gMC->Gsatt("TSCE","COLO",6);
gMC->Gsatt("TSCE","SEEN",1);
gMC->Gsatt("TWES","SEEN",0);
gMC->Gsatt("TSWB","SEEN",0);
gMC->Gsatt("TPEL","SEEN",0);
gMC->Gsatt("TPMW","SEEN",1);
gMC->Gsatt("TESR","SEEN",1);
gMC->Gsatt("TPMW","COLO",12);
gMC->Gsatt("TIC1","COLO",5);
gMC->Gsatt("TOC1","COLO",5);
gMC->Gsatt("TESB","SEEN",0);
gMC->Gsatt("THVM","SEEN",1);
gMC->Gsatt("THVM","COLO",11);
gMC->Gsatt("THVH","SEEN",0);
gMC->Gsatt("TPSR","SEEN",0);
gMC->Gsatt("THVL","SEEN",0);
gMC->Gsatt("THVC","SEEN",0);
gMC->Gsatt("THVE","SEEN",0);
gMC->Gsatt("THVR","SEEN",0);
//
gMC->Gdopt("hide", "on");
gMC->Gdopt("shad", "on");
gMC->Gsatt("*", "fill", 7);
gMC->SetClipBox(".");
gMC->SetClipBox("TPMW",-300,300,-300,300,254.,270.);
gMC->SetClipBox("TESR",-300,300,-300,300,254.,270.);
gMC->SetClipBox("TSSW",-300,300,-300,300,283.,284.);
gMC->SetClipBox("TSWC",-300,300,-300,300,283.,284.);
gMC->SetClipBox("*", 0, 300, -300, 300, -290, 290);
gMC->DefaultRange();
gMC->Gdraw("alic", 40, 30, 0, 12, 9.5, .025, .025);
gMC->Gdhead(1111, "Time Projection Chamber");
gMC->Gdman(18, 4, "MAN");
gMC->Gdopt("hide","off");
}
//_____________________________________________________________________________
void AliTPCv3::CreateMaterials()
{
//
// Define materials for version 2 of the Time Projection Chamber
//
//
AliTPC::CreateMaterials();
}
//_____________________________________________________________________________
void AliTPCv3::Init()
{
//
// Initialises version 3 of the TPC after that it has been built
//
Int_t *idtmed = fIdtmed->GetArray();
AliTPC::Init();
fIdSens=gMC->VolId("TPC_Drift"); // drift gas as a sensitive volume
gMC->SetMaxNStep(30000); // max. number of steps increased
gMC->Gstpar(idtmed[2],"LOSS",5);
printf("%s: *** TPC version 3 initialized***\n",ClassName());
printf("%s: Maximum number of steps = %d\n",ClassName(),gMC->GetMaxNStep());
// printf("*** TPC version 3 initialized ***\n");
// printf("Maximum number of steps = %d\n",gMC->GetMaxNStep());
//
}
//_____________________________________________________________________________
void AliTPCv3::StepManager()
{
//
// Called for every step in the Time Projection Chamber
//
//
// parameters used for the energy loss calculations
//
const Float_t kprim = 14.35; // number of primary collisions per 1 cm
const Float_t kpoti = 20.77e-9; // first ionization potential for Ne/CO2
const Float_t kwIon = 35.97e-9; // energy for the ion-electron pair creation
const Float_t kbig = 1.e10;
Int_t id,copy;
TLorentzVector pos;
Float_t hits[5];
Int_t vol[2];
vol[1]=0;
vol[0]=0;
//
gMC->SetMaxStep(kbig);
if(!gMC->IsTrackAlive()) return; // particle has disappeared
Float_t charge = gMC->TrackCharge();
if(TMath::Abs(charge)<=0.) return; // take only charged particles
id=gMC->CurrentVolID(copy);
if (id != fIdSens) return;
//
// charged particle is in the sensitive volume
//
if(gMC->TrackStep() > 0) {
Int_t nel = (Int_t)(((gMC->Edep())-kpoti)/kwIon) + 1;
nel=TMath::Min(nel,300); // 300 electrons corresponds to 10 keV
gMC->TrackPosition(pos);
hits[0]=pos[0];
hits[1]=pos[1];
hits[2]=pos[2];
// Get also the track time for pileup simulation
hits[4]=gMC->TrackTime();
//
// check the selected side of the TPC
//
if(fSide && fSide*hits[2]<=0.) return;
hits[3]=(Float_t)nel;
// Add this hit
AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber(), vol,hits); //MI change
}
// Stemax calculation for the next step
Float_t pp;
TLorentzVector mom;
gMC->TrackMomentum(mom);
Float_t ptot=mom.Rho();
Float_t betaGamma = ptot/gMC->TrackMass();
Int_t pid=gMC->TrackPid();
if((pid==kElectron || pid==kPositron) && ptot > 0.002)
{
pp = kprim*1.58; // electrons above 20 MeV/c are on the plateau!
}
else
{
betaGamma = TMath::Max(betaGamma,(Float_t)7.e-3);
pp=kprim*BetheBloch(betaGamma);
if(TMath::Abs(charge) > 1.) pp *= (charge*charge);
}
Double_t rnd = gMC->GetRandom()->Rndm();
gMC->SetMaxStep(-TMath::Log(rnd)/pp);
}
//_____________________________________________________________________________
Float_t AliTPCv3::BetheBloch(Float_t bg)
{
//
// Bethe-Bloch energy loss formula
//
const Double_t kp1=0.76176e-1;
const Double_t kp2=10.632;
const Double_t kp3=0.13279e-4;
const Double_t kp4=1.8631;
const Double_t kp5=1.9479;
Double_t dbg = (Double_t) bg;
Double_t beta = dbg/TMath::Sqrt(1.+dbg*dbg);
Double_t aa = TMath::Power(beta,kp4);
Double_t bb = TMath::Power(1./dbg,kp5);
bb=TMath::Log(kp3+bb);
return ((Float_t)((kp2-aa-bb)*kp1/aa));
}