ITS/AliCascadeComparison.C

   1 /****************************************************************************
   2  *           Very important, delicate and rather obscure macro.             *
   3  *                                                                          *
   4  *               Creates list of "findable" cascades,                       *
   5  *             calculates efficiency, resolutions etc.                      *
   6  *                                                                          *
   7  *  Origin: Christian Kuhn, IReS, Strasbourg, christian.kuhn@ires.in2p3.fr  *
   8  ****************************************************************************/
   9
  10 #if !defined(__CINT__) || defined(__MAKECINT__)
  11   #include <Riostream.h>
  12   #include <fstream.h>
  13
  14   #include "AliRun.h"
  15   #include "AliHeader.h"
  16   #include "AliRunLoader.h"
  17   #include "AliITSLoader.h"
  18
  19   #include "TH1.h"
  20   #include "TFile.h"
  21   #include "TTree.h"
  22   #include "TObjArray.h"
  23   #include "TStyle.h"
  24   #include "TCanvas.h"
  25   #include "TLine.h"
  26   #include "TText.h"
  27   #include "TParticle.h"
  28   #include "TStopwatch.h"
  29   #include "TPDGCode.h"
  30
  31   #include "AliRun.h"
  32   #include "AliPDG.h"
  33   #include "AliCascadeVertex.h"
  34 #endif
  35
  36 struct GoodCascade {
  37   Int_t nlab,plab;   // V0's daughter labels
  38   Int_t blab;        // Bachelor label
  39   Int_t code;
  40   Float_t px,py,pz;
  41   Float_t x,y,z;
  42 };
  43 Int_t good_cascades(GoodCascade *gt, Int_t max);
  44
  45 extern AliRun *gAlice;
  46
  47 Int_t AliCascadeComparison(Int_t code=3312) {
  48   //code= 3312; //kXiMinus
  49   //code=-3312; //kXiPlusBar
  50   //code= 3334; //kOmegaMinus
  51   //code=-3334; //kOmegaPlusBar
  52
  53    cerr<<"Doing comparison...\n";
  54
  55    TStopwatch timer;
  56
  57    const Double_t cascadeWindow=0.05, cascadeWidth=0.015;
  58    Double_t ptncut=0.12, ptpcut=0.33, kine0cut=0.003;
  59    Double_t ptbcut=0.11, kinecut=0.002;
  60    Double_t cascadeMass=1.32131;
  61    switch (code) {
  62    case kXiMinus:
  63         break;
  64    case kXiPlusBar:
  65         ptncut=0.33; ptpcut=0.12;
  66         break;
  67    case kOmegaMinus:
  68         cascadeMass=1.67245;
  69         kine0cut=0.001;
  70         ptbcut=0.22; kinecut=0.006;
  71         break;
  72    case kOmegaPlusBar:
  73         cascadeMass=1.67245;
  74         kine0cut=0.001;
  75         ptncut=0.33; ptpcut=0.12;
  76         ptbcut=0.22; kinecut=0.006;
  77         break;
  78    default: cerr<<"Invalid PDG code !\n"; return 1;
  79    }
  80
  81    /*** create some histograms ***/
  82    TH1F *hp=new TH1F("hp","Angular Resolution",30,-30.,30.); //phi resolution
  83    hp->SetXTitle("(mrad)"); hp->SetFillColor(2);
  84    TH1F *hl=new TH1F("hl","Lambda Resolution",30,-30,30);
  85    hl->SetXTitle("(mrad)"); hl->SetFillColor(1); hl->SetFillStyle(3013);
  86    TH1F *hpt=new TH1F("hpt","Relative Pt Resolution",30,-10.,10.);
  87    hpt->SetXTitle("(%)"); hpt->SetFillColor(2);
  88
  89    TH1F *hx=new TH1F("hx","Position Resolution (X,Y)",30,-3.,3.); //x res.
  90    hx->SetXTitle("(mm)"); hx->SetFillColor(6);
  91    TH1F *hy=new TH1F("hy","Position Resolution (Y)",30,-3.,3.);   //y res
  92    hy->SetXTitle("(mm)"); hy->SetFillColor(1); hy->SetFillStyle(3013);
  93    TH1F *hz=new TH1F("hz","Position Resolution (Z)",30,-3.,3.);   //z res.
  94    hz->SetXTitle("(mm)"); hz->SetFillColor(6);
  95
  96    Double_t pmin=0.2, pmax=4.2; Int_t nchan=20;
  97    TH1F *hgood=new TH1F("hgood","Good Cascades",nchan,pmin,pmax);
  98    TH1F *hfound=new TH1F("hfound","Found Cascades",nchan,pmin,pmax);
  99    TH1F *hfake=new TH1F("hfake","Fake Cascades",nchan,pmin,pmax);
 100    TH1F *hg=new TH1F("hg","Efficiency for Good Cascades",nchan,pmin,pmax);
 101    hg->SetLineColor(4); hg->SetLineWidth(2);
 102    TH1F *hf=new TH1F("hf","Probability of Fake Cascades",nchan,pmin,pmax);
 103    hf->SetFillColor(1); hf->SetFillStyle(3013); hf->SetLineWidth(2);
 104
 105    Double_t mmin=cascadeMass-cascadeWindow, mmax=cascadeMass+cascadeWindow;
 106    TH1F *cs =new TH1F("cs","Cascade Effective Mass",40, mmin, mmax);
 107    cs->SetXTitle("(GeV)");
 108    cs->SetLineColor(4); cs->SetLineWidth(4);
 109    TH1F *csf =new TH1F("csf","Fake Cascade Effective Mass",40, mmin, mmax);
 110    csf->SetXTitle("(GeV)"); csf->SetFillColor(6);
 111
 112    if (gAlice) {
 113       delete gAlice->GetRunLoader();
 114       delete gAlice;
 115       gAlice=0;
 116    }
 117    AliRunLoader *rl = AliRunLoader::Open("galice.root");
 118    if (!rl) {
 119        cerr<<"AliV0Comparison.C :Can't start sesion !\n";
 120        return 1;
 121    }
 122    AliITSLoader* itsl = (AliITSLoader*)rl->GetLoader("ITSLoader");
 123    if (itsl == 0x0) {
 124        cerr<<"AliV0Comparison.C : Can not find the ITSLoader\n";
 125        delete rl;
 126        return 2;
 127    }
 128
 129    /*** Load reconstructed cascades ***/
 130    TObjArray carray(1000);
 131    itsl->LoadCascades();
 132    TTree *xTree=itsl->TreeX();
 133    TBranch *branch=xTree->GetBranch("cascades");
 134    Int_t nentr=(Int_t)xTree->GetEntries();
 135    for (Int_t i=0; i<nentr; i++) {
 136        AliCascadeVertex *iovertex=new AliCascadeVertex;
 137        branch->SetAddress(&iovertex);
 138        xTree->GetEvent(i);
 139        carray.AddLast(iovertex);
 140    }
 141
 142    /*** Check if the file with the "good" cascades exists ***/
 143    GoodCascade gc[100];
 144    Int_t ngood=0;
 145    ifstream in("good_cascades");
 146    if (in) {
 147       cerr<<"Reading good cascades...\n";
 148       while (in>>gc[ngood].nlab>>gc[ngood].plab>>
 149                  gc[ngood].blab>>gc[ngood].code>>
 150                  gc[ngood].px>>gc[ngood].py>>gc[ngood].pz>>
 151                  gc[ngood].x >>gc[ngood].y >>gc[ngood].z) {
 152          ngood++;
 153          cerr<<ngood<<'\r';
 154          if (ngood==100) {
 155             cerr<<"Too many good cascades !\n";
 156             break;
 157          }
 158       }
 159       if (!in.eof()) cerr<<"Read error (good_cascades) !\n";
 160    } else {
 161      /*** generate a file with the "good" cascades ***/
 162       cerr<<"Marking good cascades (this will take a while)...\n";
 163       ngood=good_cascades(gc,100);
 164       ofstream out("good_cascades");
 165       if (out) {
 166          for (Int_t ngd=0; ngd<ngood; ngd++)
 167             out<<gc[ngd].nlab<<' '<<gc[ngd].plab<<' '<<
 168                  gc[ngd].blab<<' '<<gc[ngd].code<<' '<<
 169                  gc[ngd].px<<' '<<gc[ngd].py<<' '<<gc[ngd].pz<<' '<<
 170                  gc[ngd].x <<' '<<gc[ngd].y <<' '<<gc[ngd].z <<endl;
 171       } else cerr<<"Can not open file (good_cascades) !\n";
 172       out.close();
 173    }
 174
 175    Double_t pxg=0.,pyg=0.,ptg=0.;
 176    Int_t nlab=-1, plab=-1, blab=-1;
 177    Int_t i;
 178    for (i=0; i<nentr; i++) {
 179        AliCascadeVertex *cascade=(AliCascadeVertex*)carray.UncheckedAt(i);
 180        nlab=TMath::Abs(cascade->GetNlabel());
 181        plab=TMath::Abs(cascade->GetPlabel());
 182        blab=TMath::Abs(cascade->GetBlabel());
 183
 184        /** Kinematical cuts **/
 185        Double_t pxn,pyn,pzn; cascade->GetNPxPyPz(pxn,pyn,pzn);
 186        Double_t ptn=TMath::Sqrt(pxn*pxn + pyn*pyn);
 187        if (ptn < ptncut) continue;
 188        Double_t pxp,pyp,pzp; cascade->GetPPxPyPz(pxp,pyp,pzp);
 189        Double_t ptp=TMath::Sqrt(pxp*pxp + pyp*pyp);
 190        if (ptp < ptpcut) continue;
 191        Double_t pxb,pyb,pzb; cascade->GetBPxPyPz(pxb,pyb,pzb);
 192        Double_t ptb=TMath::Sqrt(pxb*pxb + pyb*pyb);
 193        if (ptb < ptbcut) continue;
 194        Double_t kine0;
 195        Double_t kine=cascade->ChangeMassHypothesis(kine0,code);
 196        if (TMath::Abs(kine0)>kine0cut) continue;
 197        //if (TMath::Abs(kine)>kinecut) continue;
 198
 199        Double_t mass=cascade->GetEffMass();
 200        cs->Fill(mass);
 201        csf->Fill(mass);
 202
 203        if (TMath::Abs(mass-cascadeMass)>cascadeWidth) continue;
 204
 205        Int_t j;
 206        for (j=0; j<ngood; j++) {
 207           if (gc[j].code != cascade->GetPdgCode()) continue;
 208           if (gc[j].nlab == nlab)
 209           if (gc[j].plab == plab)
 210           if (gc[j].blab == blab) break;
 211        }
 212
 213        Double_t px,py,pz; cascade->GetPxPyPz(px,py,pz);
 214        Double_t pt=TMath::Sqrt(px*px+py*py);
 215
 216        if (j==ngood) {
 217           hfake->Fill(pt);
 218           cerr<<"Fake cascade: ("<<nlab<<","<<plab<<","<<blab<<")\n";
 219           continue;
 220        }
 221        csf->Fill(mass,-1);
 222
 223        pxg=gc[j].px; pyg=gc[j].py; ptg=TMath::Sqrt(pxg*pxg+pyg*pyg);
 224        Double_t phig=TMath::ATan2(pyg,pxg), phi=TMath::ATan2(py,px);
 225        Double_t lamg=TMath::ATan2(gc[j].pz,ptg), lam=TMath::ATan2(pz,pt);
 226        hp->Fill((phi - phig)*1000.);
 227        hl->Fill((lam - lamg)*1000.);
 228        hpt->Fill((1/pt - 1/ptg)/(1/ptg)*100.);
 229
 230        Double_t x,y,z; cascade->GetXYZ(x,y,z);
 231        hx->Fill((x-gc[j].x)*10);
 232        hy->Fill((y-gc[j].y)*10);
 233        hz->Fill((z-gc[j].z)*10);
 234
 235        hfound->Fill(ptg);
 236        gc[j].nlab=-1;
 237
 238    }
 239    for (i=0; i<ngood; i++) {
 240       if (gc[i].code != code) continue;
 241       pxg=gc[i].px; pyg=gc[i].py; ptg=TMath::Sqrt(pxg*pxg+pyg*pyg);
 242       hgood->Fill(ptg);
 243       nlab=gc[i].nlab; plab=gc[i].plab; blab=gc[i].blab;
 244       if (nlab < 0) continue;
 245      cerr<<"Cascade ("<<nlab<<','<<plab<<","<<blab<<") has not been found !\n";
 246    }
 247
 248    carray.Delete();
 249
 250    Stat_t ng=hgood->GetEntries();
 251    Stat_t nf=hfound->GetEntries();
 252
 253    cerr<<"Number of found cascades: "<<nentr<<" ("<<nf<<" in the peak)\n";
 254    cerr<<"Number of good cascades: "<<ng<<endl;
 255
 256    if (ng!=0)
 257       cerr<<"Integral efficiency is about "<<nf/ng*100.<<" %\n";
 258
 259    gStyle->SetOptStat(111110);
 260    gStyle->SetOptFit(1);
 261
 262    TCanvas *c1=new TCanvas("c1","",0,0,580,610);
 263    c1->Divide(2,2);
 264
 265    c1->cd(1);
 266    gPad->SetFillColor(42); gPad->SetFrameFillColor(10);
 267    //hp->Fit("gaus");
 268    hp->Draw();
 269    hl->Draw("same"); c1->cd();
 270
 271    c1->cd(2);
 272    gPad->SetFillColor(42); gPad->SetFrameFillColor(10);
 273    //hpt->Fit("gaus"); c1->cd();
 274    hpt->Draw(); c1->cd();
 275
 276    c1->cd(3);
 277    gPad->SetFillColor(42); gPad->SetFrameFillColor(10);
 278    //hx->Fit("gaus");
 279    hx->Draw();
 280    hy->Draw("same"); c1->cd();
 281
 282    c1->cd(4);
 283    gPad->SetFillColor(42); gPad->SetFrameFillColor(10);
 284    //hz->Fit("gaus");
 285    hz->Draw();
 286
 287
 288    TCanvas *c2=new TCanvas("c2","",600,0,580,610);
 289    c2->Divide(1,2);
 290
 291    c2->cd(1);
 292    gPad->SetFillColor(42); gPad->SetFrameFillColor(10);
 293    hfound->Sumw2(); hgood->Sumw2(); hfake->Sumw2();
 294    hg->Divide(hfound,hgood,1,1.,"b");
 295    hf->Divide(hfake,hgood,1,1.,"b");
 296    hg->SetMaximum(1.4);
 297    hg->SetYTitle("Cascade reconstruction efficiency");
 298    hg->SetXTitle("Pt (GeV/c)");
 299    hg->Draw();
 300
 301    TLine *line1 = new TLine(pmin,1.0,pmax,1.0); line1->SetLineStyle(4);
 302    line1->Draw("same");
 303    TLine *line2 = new TLine(pmin,0.9,pmax,0.9); line2->SetLineStyle(4);
 304    line2->Draw("same");
 305
 306    hf->SetFillColor(1);
 307    hf->SetFillStyle(3013);
 308    hf->SetLineColor(2);
 309    hf->SetLineWidth(2);
 310    hf->Draw("histsame");
 311    TText *text = new TText(0.461176,0.248448,"Fake cascades");
 312    text->SetTextSize(0.05);
 313    text->Draw();
 314    text = new TText(0.453919,1.11408,"Good cascades");
 315    text->SetTextSize(0.05);
 316    text->Draw();
 317
 318
 319    c2->cd(2);
 320    gPad->SetFillColor(42); gPad->SetFrameFillColor(10);
 321    //cs->Fit("gaus","","",cascadeMass-cascadeWidth,cascadeMass+cascadeWidth);
 322    cs->Draw();
 323    csf->Draw("same");
 324    Double_t max=cs->GetMaximum();
 325    TLine *line3 =
 326       new TLine(cascadeMass-cascadeWidth,0.,cascadeMass-cascadeWidth,max);
 327    line3->Draw("same");
 328    TLine *line4 =
 329       new TLine(cascadeMass+cascadeWidth,0.,cascadeMass+cascadeWidth,max);
 330    line4->Draw("same");
 331
 332    timer.Stop(); timer.Print();
 333
 334    delete rl;
 335
 336    return 0;
 337 }
 338
 339
 340 Int_t good_cascades(GoodCascade *gc, Int_t max) {
 341    Int_t nc=0;
 342    /*** Get information about the cuts ***/
 343    Double_t r2min=0.9*0.9;
 344    Double_t r2max=2.9*2.9;
 345
 346    /*** Get labels of the "good" tracks ***/
 347    Double_t dd; Int_t id, label[15000], ngt=0;
 348    ifstream in("good_tracks_its");
 349    if (!in) {
 350      cerr<<"Can't open the file good_tracks_its \n";
 351      return nc;
 352    }
 353    while (in>>label[ngt]>>id>>dd>>dd>>dd>>dd>>dd>>dd) {
 354      ngt++;
 355      if (ngt>=15000) {
 356        cerr<<"Too many good ITS tracks !\n";
 357        return nc;
 358      }
 359    }
 360    if (!in.eof()) {
 361       cerr<<"Read error (good_tracks_its) !\n";
 362       return nc;
 363    }
 364
 365    /*** Get an access to the kinematics ***/
 366    AliRunLoader *rl =
 367         AliRunLoader::GetRunLoader(AliConfig::fgkDefaultEventFolderName);
 368    if (rl == 0x0) {
 369   ::Fatal("AliCascadeComparison.C::good_cascades","Can not find Run Loader !");
 370    }
 371
 372    AliITSLoader* itsl = (AliITSLoader*)rl->GetLoader("ITSLoader");
 373    if (itsl == 0x0) {
 374        cerr<<"AliITSComparisonV2.C : Can not find TPCLoader\n";
 375        delete rl;
 376        return 1;
 377    }
 378    rl->LoadgAlice();
 379    rl->LoadHeader();
 380    rl->LoadKinematics();
 381    Int_t np = rl->GetHeader()->GetNtrack();
 382
 383    while (np--) {
 384       cerr<<np<<'\r';
 385       TParticle *cp=gAlice->Particle(np);
 386
 387       /*** only these cascades are "good" ***/
 388       Int_t code=cp->GetPdgCode();
 389       if (code!=kXiMinus)    if (code!=kXiPlusBar)
 390       if (code!=kOmegaMinus) if (code!=kOmegaPlusBar) continue;
 391
 392       /*** daughter tracks must be "good" ***/
 393       Int_t v0lab=cp->GetFirstDaughter(), blab=cp->GetLastDaughter();
 394       if (v0lab==blab) continue;
 395       if (v0lab<0) continue;
 396       if (blab<0) continue;
 397
 398       TParticle *p0=gAlice->Particle(v0lab);
 399       TParticle *bp=gAlice->Particle(blab);
 400       if ((p0->GetPdgCode()!=kLambda0) && (p0->GetPdgCode()!=kLambda0Bar)) {
 401          TParticle *p=p0; p0=bp; bp=p;
 402          Int_t i=v0lab; v0lab=blab; blab=i;
 403          if ((p0->GetPdgCode()!=kLambda0) && (p0->GetPdgCode()!=kLambda0Bar))
 404                                                                    continue;
 405       }
 406
 407       /** is the bachelor "good" ? **/
 408       Int_t i;
 409       for (i=0; i<ngt; i++) if (label[i]==blab) break;
 410       if (i==ngt) continue;
 411
 412       /** is the V0 "good" ? **/
 413       Int_t plab=p0->GetFirstDaughter(), nlab=p0->GetLastDaughter();
 414       if (nlab==plab) continue;
 415       if (nlab<0) continue;
 416       if (plab<0) continue;
 417
 418       for (i=0; i<ngt; i++) if (label[i]==nlab) break;
 419       if (i==ngt) continue;
 420       for (i=0; i<ngt; i++) if (label[i]==plab) break;
 421       if (i==ngt) continue;
 422
 423       /*** fiducial volume ***/
 424       Double_t x=bp->Vx(), y=bp->Vy(), r2=x*x+y*y; //bachelor
 425       if (r2<r2min) continue;
 426       if (r2>r2max) continue;
 427       TParticle *pp=gAlice->Particle(plab);
 428       x=pp->Vx(); y=pp->Vy(); r2=x*x+y*y;                      //V0
 429       if (r2<r2min) continue;
 430       if (r2>r2max) continue;
 431
 432       if (gAlice->Particle(plab)->GetPDG()->Charge() < 0.) {
 433          i=plab; plab=nlab; nlab=i;
 434       }
 435
 436       gc[nc].code=code;
 437       gc[nc].plab=plab;   gc[nc].nlab=nlab; gc[nc].blab=blab;
 438       gc[nc].px=cp->Px(); gc[nc].py=cp->Py(); gc[nc].pz=cp->Pz();
 439       gc[nc].x=bp->Vx(); gc[nc].y=bp->Vy(); gc[nc].z=bp->Vz();
 440       nc++;
 441
 442    }
 443
 444    delete rl;
 445
 446    return nc;
 447 }