#include <TtDecayChannelSelector.h>

Public Types
enum	{ Elec = 0, Muon = 1, Tau = 2 }
	leafs of leptonic decay channel vector decay_ More...

typedef std::vector< int >	Decay
	typedef to simplify the decay vectors More...

Public Member Functions
bool	operator() (const reco::GenParticleCollection &parts, std::string inputType) const
	operator for decay channel selection More...

	TtDecayChannelSelector (const edm::ParameterSet &)
	std contructor More...

	~TtDecayChannelSelector ()
	default destructor More...

Private Member Functions
unsigned int	checkSum (const Decay &vec) const

unsigned int	countProngs (const reco::Candidate &part) const
	count the number of charged particles for tau decays More...

unsigned int	decayChannel () const
	return decay channel to select for from configuration More...

bool	search (reco::GenParticleCollection::const_iterator &part, int pdgId, std::string &inputType) const
	search for particle with pdgId in given listing (for top) More...

bool	search (reco::GenParticle::const_iterator &part, int pdgId, std::string &inputType) const
	search for particle with pdgId in given listing (for top daughters) More...

bool	tauDecay (const reco::Candidate &) const
	check tau decay to be leptonic, 1-prong or 3-prong More...

Private Attributes
bool	allow1Prong_
	allow 1-prong tau decays More...

bool	allow3Prong_
	allow 2-prong tau decays More...

Decay	allowedDecays_

bool	allowElectron_
	allow tau decays into electron More...

bool	allowMuon_
	allow tau decays into muon More...

Decay	decayBranchA_
	top decay branch 1 More...

Decay	decayBranchB_
	top decay branch 2 More...

bool	invert_
	invert selection More...

bool	restrictTauDecays_
	restrict tau decays More...

Detailed Description

Definition at line 8 of file TtDecayChannelSelector.h.

Member Typedef Documentation

typedef std::vector<int> TtDecayChannelSelector::Decay

typedef to simplify the decay vectors

Definition at line 13 of file TtDecayChannelSelector.h.

Member Enumeration Documentation

anonymous enum

leafs of leptonic decay channel vector decay_

Enumerator
Elec
Muon
Tau

Definition at line 11 of file TtDecayChannelSelector.h.

11 { Elec = 0, Muon = 1, Tau = 2 };

Muon

Definition: Muon.py:1

TtDecayChannelSelector::Elec

Definition: TtDecayChannelSelector.h:11

Tau

Definition: Tau.py:1

Constructor & Destructor Documentation

TtDecayChannelSelector::TtDecayChannelSelector ( const edm::ParameterSet & cfg )

std contructor

Definition at line 15 of file TtDecayChannelSelector.cc.

References allow1Prong_, allow3Prong_, allowedDecays_, TtDecayChannelFilter_cfi::allowedTopDecays, allowElectron_, allowMuon_, ztail::d, TtDecayChannelFilter_cfi::decayBranchA, decayBranchA_, TtDecayChannelFilter_cfi::decayBranchB, decayBranchB_, edm::ParameterSet::existsAs(), edm::ParameterSet::getParameter(), kDecayChannels, and restrictTauDecays_.

     : invert_(cfg.getParameter<bool>("invert")),
       allowElectron_(false),
       allowMuon_(false),
       allow1Prong_(false),
       allow3Prong_(false) {
   // tau decays are not restricted if this PSet does not exist at all
   restrictTauDecays_ = cfg.existsAs<edm::ParameterSet>("restrictTauDecays");
   // determine allowed tau decays
   if (restrictTauDecays_) {
     edm::ParameterSet allowedTauDecays = cfg.getParameter<edm::ParameterSet>("restrictTauDecays");
     // tau decays are not restricted if none of the following parameters exists
     restrictTauDecays_ = (allowedTauDecays.existsAs<bool>("electron") || allowedTauDecays.existsAs<bool>("muon") ||
                           allowedTauDecays.existsAs<bool>("oneProng") || allowedTauDecays.existsAs<bool>("threeProng"));
     // specify the different possible restrictions of the tau decay channels
     allowElectron_ =
         (allowedTauDecays.existsAs<bool>("electron") ? allowedTauDecays.getParameter<bool>("electron") : false);
     allowMuon_ = (allowedTauDecays.existsAs<bool>("muon") ? allowedTauDecays.getParameter<bool>("muon") : false);
     allow1Prong_ =
         (allowedTauDecays.existsAs<bool>("oneProng") ? allowedTauDecays.getParameter<bool>("oneProng") : false);
     allow3Prong_ =
         (allowedTauDecays.existsAs<bool>("threeProng") ? allowedTauDecays.getParameter<bool>("threeProng") : false);
   }
   // allowed top decays PSet
   edm::ParameterSet allowedTopDecays = cfg.getParameter<edm::ParameterSet>("allowedTopDecays");
 
   // fill decayBranchA_
   edm::ParameterSet decayBranchA = allowedTopDecays.getParameter<edm::ParameterSet>("decayBranchA");
   decayBranchA_.push_back(decayBranchA.getParameter<bool>("electron"));
   decayBranchA_.push_back(decayBranchA.getParameter<bool>("muon"));
   decayBranchA_.push_back(decayBranchA.getParameter<bool>("tau"));
 
   // fill decay branchB_
   edm::ParameterSet decayBranchB = allowedTopDecays.getParameter<edm::ParameterSet>("decayBranchB");
   decayBranchB_.push_back(decayBranchB.getParameter<bool>("electron"));
   decayBranchB_.push_back(decayBranchB.getParameter<bool>("muon"));
   decayBranchB_.push_back(decayBranchB.getParameter<bool>("tau"));
 
   // fill allowedDecays_
   for (unsigned int d = 0; d < kDecayChannels; ++d) {
     allowedDecays_.push_back(decayBranchA_[d] + decayBranchB_[d]);
   }
 }

TtDecayChannelSelector::~TtDecayChannelSelector ( )

default destructor

Definition at line 59 of file TtDecayChannelSelector.cc.

59 {}

Member Function Documentation

unsigned int TtDecayChannelSelector::checkSum ( const Decay & vec ) const

inlineprivate

Definition at line 69 of file TtDecayChannelSelector.h.

References ztail::d.

Referenced by operator()().

                                                                            {
   unsigned int sum = 0;
   for (unsigned int d = 0; d < vec.size(); ++d) {
     sum += vec[d];
   }
   return sum;
 }

unsigned int TtDecayChannelSelector::countProngs ( const reco::Candidate & part ) const

private

count the number of charged particles for tau decays

Definition at line 186 of file TtDecayChannelSelector.cc.

References reco::Candidate::begin(), reco::Candidate::charge(), reco::Candidate::end(), and reco::Candidate::status().

Referenced by tauDecay().

                                                                                 {
   // if stable, return 1 or 0
   if (part.status() == 1) {
     return (part.charge() != 0);
   }
   // if unstable, call recursively on daughters
   int prong = 0;
   for (reco::Candidate::const_iterator daughter = part.begin(); daughter != part.end(); ++daughter) {
     prong += countProngs(*daughter);
   }
   return prong;
 }

unsigned int TtDecayChannelSelector::decayChannel ( ) const

inlineprivate

return decay channel to select for from configuration

Definition at line 58 of file TtDecayChannelSelector.h.

References KineDebug3::count(), decayBranchA_, and decayBranchB_.

Referenced by operator()().

                                                                {
   unsigned int channel = 0;
   if (std::count(decayBranchA_.begin(), decayBranchA_.end(), 1) > 0) {
     ++channel;
   }
   if (std::count(decayBranchB_.begin(), decayBranchB_.end(), 1) > 0) {
     ++channel;
   }
   return channel;
 }

bool TtDecayChannelSelector::operator()	(	const reco::GenParticleCollection &	parts,
		std::string	inputType
	)		const

operator for decay channel selection

Definition at line 61 of file TtDecayChannelSelector.cc.

References funct::abs(), accept(), allowedDecays_, reco::Candidate::begin(), TopDecayID::bID, checkSum(), decayBranchA_, decayBranchB_, decayChannel(), Elec, TopDecayID::elecID, reco::Candidate::end(), createfilelist::int, invert_, dqm-mbProfile::log, Muon, TopDecayID::muonID, restrictTauDecays_, search(), Tau, tauDecay(), TopDecayID::tauID, TopDecayID::tID, and TopDecayID::WID.

                                                                                                          {
   bool verbose =
       false;  // set this to true for debugging and add TtDecayChannelSelector category to the MessageLogger in your cfg file
   unsigned int iLep = 0;
   unsigned int iTop = 0, iBeauty = 0, iElec = 0, iMuon = 0, iTau = 0;
   for (reco::GenParticleCollection::const_iterator top = parts.begin(); top != parts.end(); ++top) {
     if (search(top, TopDecayID::tID, inputType)) {
       ++iTop;
       for (reco::GenParticle::const_iterator td = top->begin(); td != top->end(); ++td) {
         if (search(td, TopDecayID::bID, inputType)) {
           ++iBeauty;
         }
         if (search(td, TopDecayID::WID, inputType)) {
           for (reco::GenParticle::const_iterator wd = td->begin(); wd != td->end(); ++wd) {
             if (std::abs(wd->pdgId()) == TopDecayID::elecID) {
               ++iElec;
             }
             if (std::abs(wd->pdgId()) == TopDecayID::muonID) {
               ++iMuon;
             }
             if (std::abs(wd->pdgId()) == TopDecayID::tauID) {
               if (restrictTauDecays_) {
                 // count as iTau if it is leptonic, one-prong
                 // or three-prong and ignore increasing iLep
                 // though else
                 if (tauDecay(*wd)) {
                   ++iTau;
                 } else {
                   ++iLep;
                 }
               } else {
                 ++iTau;
               }
             }
           }
         }
       }
     }
   }
   if (verbose) {
     edm::LogVerbatim log("TtDecayChannelSelector");
     log << "----------------------"
         << "\n"
         << " iTop    : " << iTop << "\n"
         << " iBeauty : " << iBeauty << "\n"
         << " iElec   : " << iElec << "\n"
         << " iMuon   : " << iMuon << "\n"
         << " iTau    : " << iTau + iLep;
     if (restrictTauDecays_ && (iTau + iLep) > 0) {
       log << " (" << iTau << ")\n";
     } else {
       log << "\n";
     }
     log << "- - - - - - - - - - - "
         << "\n";
   }
   iLep += iElec + iMuon + iTau;
 
   bool accept = false;
   unsigned int channel = decayChannel();
   if ((iTop == 2) && (iBeauty == 2)) {
     if (channel == iLep) {
       if (channel == 0) {
         // no lepton: accept without restriction we already
         // know that the number of leptons is correct
         accept = true;
       }
       if (channel == 1) {
         // one lepton: check that this one is allowed
         accept = (iElec && allowedDecays_[Elec]) || (iMuon && allowedDecays_[Muon]) || (iTau && allowedDecays_[Tau]);
       }
       if (channel == 2) {
         if (checkSum(allowedDecays_) == channel) {
           // no redundancy
           accept = (allowedDecays_[Elec] == (int)iElec) && (allowedDecays_[Muon] == (int)iMuon) &&
                    (allowedDecays_[Tau] == (int)iTau);
         } else {
           // reject events with wrong tau decays
           if (iElec + iMuon + iTau != channel) {
             accept = false;
           } else {
             if ((iElec == 2) || (iMuon == 2) || (iTau == 2)) {
               // same lepton twice: check that this is allowed.
               accept = (allowedDecays_[Elec] == (int)iElec) || (allowedDecays_[Muon] == (int)iMuon) ||
                        (allowedDecays_[Tau] == (int)iTau);
             } else {
               // two different leptons: look if there is a possible combination
               accept = (((iElec && decayBranchA_[Elec]) &&
                          ((iMuon && decayBranchB_[Muon]) || (iTau && decayBranchB_[Tau]))) ||
                         ((iMuon && decayBranchA_[Muon]) &&
                          ((iElec && decayBranchB_[Elec]) || (iTau && decayBranchB_[Tau]))) ||
                         ((iTau && decayBranchA_[Tau]) &&
                          ((iElec && decayBranchB_[Elec]) || (iMuon && decayBranchB_[Muon]))));
             }
           }
         }
       }
     }
     accept = ((!invert_ && accept) || (!(!invert_) && !accept));
   } else {
     edm::LogWarning("NoVtbDecay") << "Decay is not via Vtb";
   }
   if (verbose)
     edm::LogVerbatim("TtDecayChannelSelector") << " accept  : " << accept;
   return accept;
 }

bool TtDecayChannelSelector::search	(	reco::GenParticleCollection::const_iterator &	part,
		int	pdgId,
		std::string &	inputType
	)		const

private

search for particle with pdgId in given listing (for top)

Definition at line 168 of file TtDecayChannelSelector.cc.

References funct::abs(), kGenParticles, and TopDecayID::unfrag.

Referenced by operator()().

                                                                 {
   if (inputType == kGenParticles) {
     return (std::abs(part->pdgId()) == pdgId && part->status() == TopDecayID::unfrag) ? true : false;
   } else {
     return (std::abs(part->pdgId()) == pdgId) ? true : false;
   }
 }

bool TtDecayChannelSelector::search	(	reco::GenParticle::const_iterator &	part,
		int	pdgId,
		std::string &	inputType
	)		const

private

search for particle with pdgId in given listing (for top daughters)

Definition at line 178 of file TtDecayChannelSelector.cc.

References funct::abs(), kGenParticles, reco::Candidate::pdgId(), reco::Candidate::status(), and TopDecayID::unfrag.

                                                                                                               {
   if (inputType == kGenParticles) {
     return (std::abs(part->pdgId()) == pdgId && part->status() == TopDecayID::unfrag) ? true : false;
   } else {
     return (std::abs(part->pdgId()) == pdgId) ? true : false;
   }
 }

bool TtDecayChannelSelector::tauDecay ( const reco::Candidate & tau ) const

private

check tau decay to be leptonic, 1-prong or 3-prong

Definition at line 199 of file TtDecayChannelSelector.cc.

References funct::abs(), allow1Prong_, allow3Prong_, allowElectron_, allowMuon_, reco::Candidate::begin(), countProngs(), TopDecayID::elecID, reco::Candidate::end(), TopDecayID::muonID, and reco::Candidate::pdgId().

Referenced by operator()().

                                                                     {
   bool electronTau = false;
   bool muonTau = false;
   unsigned int nch = 0;
   // loop on tau decays, check for an elec
   // or muon and count charged particles
   for (reco::Candidate::const_iterator daughter = tau.begin(); daughter != tau.end(); ++daughter) {
     // if the tau daughter is again a tau, this means that the particle has
     // still to be propagated; in that case, return the result of the same
     // method applied on the daughter of the current particle
     if (daughter->pdgId() == tau.pdgId()) {
       return tauDecay(*daughter);
     }
     // check for electron from tau decay
     electronTau |= (std::abs(daughter->pdgId()) == TopDecayID::elecID);
     // check for muon from tau decay
     muonTau |= (std::abs(daughter->pdgId()) == TopDecayID::muonID);
     // count charged particles
     nch += countProngs(*daughter);
   }
   return ((allowElectron_ && electronTau) || (allowMuon_ && muonTau) ||
           (allow1Prong_ && !electronTau && !muonTau && nch == 1) ||
           (allow3Prong_ && !electronTau && !muonTau && nch == 3));
 }