TopKinFitter/interface/TtFullLepKinSolver.h

0001 #ifndef TtFullLepKinSolver_h
0002 #define TtFullLepKinSolver_h
0003
0004 #include "AnalysisDataFormats/TopObjects/interface/TtDilepEvtSolution.h"
0005 #include "DataFormats/Candidate/interface/LeafCandidate.h"
0006
0007 #include "TLorentzVector.h"
0008 #include "TMath.h"
0009
0010 class TF2;
0011
0012 /*
0013   \class   TtFullLepKinSolver TtFullLepKinSolver.h "TopQuarkAnalysis/TopKinFitter/interface/TtFullLepKinSolver.h"
0014
0015   \brief   Class to calculate solutions for neutrino momenta in dileptonic ttbar events and related probability weights
0016
0017   Class to calculate solutions for neutrino momenta in dileptonic ttbar events and related probability weights.
0018   A fourth-order polynomial in p_x(nu) is used with coefficients that are functions of the top-quark mass.
0019   If physical (non-imaginary) solutions are found, the neutrino momenta are compared to the expected neutrino spectrum
0020   (from simulation) to obtain a probability weight for each solution.
0021   This class is based on a code by Jan Valenta.
0022
0023 **/
0024
0025 class TtFullLepKinSolver {
0026 public:
0027   ///
0028   struct NeutrinoSolution {
0029     double weight;
0030     reco::LeafCandidate neutrino;
0031     reco::LeafCandidate neutrinoBar;
0032   };
0033
0034   /// default constructor
0035   TtFullLepKinSolver();
0036   /// constructor with parameters to configure the top-mass scan and the neutrino spectrum
0037   TtFullLepKinSolver(
0038       const double, const double, const double, const std::vector<double>&, const double = 80.4, const double = 4.8);
0039   /// destructor
0040   ~TtFullLepKinSolver();
0041
0042   ///
0043   inline void useWeightFromMC(bool useMC) { useMCforBest_ = useMC; }
0044   ///
0045   TtDilepEvtSolution addKinSolInfo(TtDilepEvtSolution* asol);
0046   ///
0047   void SetConstraints(const double xx = 0, const double yy = 0);
0048   ///
0049   NeutrinoSolution getNuSolution(const TLorentzVector& LV_l,
0050                                  const TLorentzVector& LV_l_,
0051                                  const TLorentzVector& LV_b,
0052                                  const TLorentzVector& LV_b_);
0053
0054 private:
0055   ///
0056   void FindCoeff(const TLorentzVector& al,
0057                  const TLorentzVector& l,
0058                  const TLorentzVector& b_al,
0059                  const TLorentzVector& b_l,
0060                  const double mt,
0061                  const double mat,
0062                  const double pxboost,
0063                  const double pyboost,
0064                  double* q_coeff);
0065   ///
0066   void TopRec(const TLorentzVector& al,
0067               const TLorentzVector& l,
0068               const TLorentzVector& b_al,
0069               const TLorentzVector& b_l,
0070               const double sol);
0071   ///
0072   double WeightSolfromMC() const;
0073   /// use the parametrized event shape to obtain the solution weight.
0074   double WeightSolfromShape() const;
0075   ///
0076   int quartic(double* q_coeff, double* q_sol) const;
0077   ///
0078   int cubic(const double* c_coeff, double* c_sol) const;
0079   ///
0080   double sqr(const double x) const { return (x * x); }
0081   ///
0082   void SWAP(double& realone, double& realtwo) const;
0083
0084 private:
0085   ///
0086   const double topmass_begin;
0087   ///
0088   const double topmass_end;
0089   ///
0090   const double topmass_step;
0091   ///
0092   const double mw;
0093   ///
0094   const double mb;
0095   ///
0096   double pxmiss_, pymiss_;
0097
0098   double C;
0099   double D;
0100   double F;
0101   double pom;
0102   double k16;
0103   double k26;
0104   double k36;
0105   double k46;
0106   double k56;
0107   double k51;
0108   double k61;
0109   double m1;
0110   double m2;
0111   double m3;
0112   double n1;
0113   double n2;
0114   double n3;
0115
0116   ///
0117   TLorentzVector LV_n, LV_n_, LV_t, LV_t_, LV_tt_t, LV_tt_t_;
0118   /// provisional
0119   TLorentzVector genLV_n, genLV_n_;
0120
0121   /// flag to swith from WeightSolfromMC() to WeightSolfromShape()
0122   bool useMCforBest_;
0123   /// Event shape
0124   TF2* EventShape_;
0125 };
0126
0127 #endif