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B to D pre study using fast simulation

Updated on Thu, 2016-12-08 02:02. Originally created by xlchen on 2016-07-27 21:02.

 The Common cuts:
        bool isGoodTrack = t->kRPt>0.3 && fabs(t->kREta)<1 && t->pRPt>0.3 && fabs(t->pREta)<1;
        bool passTpc = t->kTpc>0 && t->pTpc>0;
        bool passHft = t->kHft > 0 && t->pHft > 0;

// use ultimate 2 topology cut 
D0 Dca histograph cuts:
       t->pRDca > anaCuts::pDca[ptIndex]

       && t->kRDca > anaCuts::kDca[ptIndex]
       && t->dca12 < anaCuts::dcaDaughters[ptIndex]
       && t->decayLength > anaCuts::decayLength[ptIndex]

pi Dca histograph cuts:

      t->kRDca > anaCuts::kDca[ptIndex]
      && t->dca12 < anaCuts::dcaDaughters[ptIndex]
      && t->decayLength > anaCuts::decayLength[ptIndex]

k Dca histograph cuts:

     t->pRDca > anaCuts::pDca[ptIndex]
     && t->dca12 < anaCuts::dcaDaughters[ptIndex]
     && t->decayLength > anaCuts::decayLength[ptIndex]

dcaDaughters histograph cuts:
     t->pRDca > anaCuts::pDca[ptIndex]

     && t->kRDca > anaCuts::kDca[ptIndex]
     && t->decayLength > anaCuts::decayLength[ptIndex]
 

decay length histograph cuts:
     t->pRDca > anaCuts::pDca[ptIndex]

     && t->kRDca > anaCuts::kDca[ptIndex]
     && t->dca12 < anaCuts::dcaDaughters[ptIndex]
 

cosTheta histograph cuts:
     t->pRDca > anaCuts::pDca[ptIndex]

     && t->kRDca > anaCuts::kDca[ptIndex]
     && t->dca12 < anaCuts::dcaDaughters[ptIndex]
     && t->decayLength > anaCuts::decayLength[ptIndex]

Scale the D0 from B+/- and B0 to 1/5 of prompt D0
Conclusions:
     1. The prompt D0 Dca can have strong seperation with B decayed D0
     2. The cosTheta from B decayed D0 is broader than prompt D0,  so the cosTheta > 0.95 cut in picoD0 may be not suitable 
 

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