EIC code displayed by LXR master/​include/​fastjet/​contrib/​ModifiedMassDropTagger.hh	Source navigation Diff markup Identifier search General search
	Version: master test Revert   Change

File indexing completed on 2025-01-18 09:57:14

 // $Id: ModifiedMassDropTagger.hh 1032 2017-07-31 14:20:03Z gsoyez $
 //
 // Copyright (c) 2014-, Gavin P. Salam
 // based on arXiv:1307.007 by Mrinal Dasgupta, Simone Marzani and Gavin P. Salam
 //
 //----------------------------------------------------------------------
 // This file is part of FastJet contrib.
 //
 // It is free software; you can redistribute it and/or modify it under
 // the terms of the GNU General Public License as published by the
 // Free Software Foundation; either version 2 of the License, or (at
 // your option) any later version.
 //
 // It is distributed in the hope that it will be useful, but WITHOUT
 // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 // or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
 // License for more details.
 //
 // You should have received a copy of the GNU General Public License
 // along with this code. If not, see <http://www.gnu.org/licenses/>.
 //----------------------------------------------------------------------
 
 #ifndef __FASTJET_CONTRIB_MODIFIEDMASSDROPTAGGER_HH__
 #define __FASTJET_CONTRIB_MODIFIEDMASSDROPTAGGER_HH__
 
 #include "RecursiveSymmetryCutBase.hh"
 
 FASTJET_BEGIN_NAMESPACE      // defined in fastjet/internal/base.hh
 
 namespace contrib{
 
 //------------------------------------------------------------------------
 /// \class ModifiedMassDropTagger
 /// An implementation of the modified Mass-Drop Tagger from arXiv:1307.0007.
 ///
 class ModifiedMassDropTagger : public RecursiveSymmetryCutBase {
 public:
   
   /// Simplified constructor, which takes just a symmetry cut (applied
   /// on the scalar_z variable) and an optional subtractor.
   ///
   /// In this incarnation the ModifiedMassDropTagger is a bit of a
   /// misnomer, because there is no mass-drop condition
   /// applied. Recursion into the jet structure chooses the prong with
   /// largest pt. (Results from arXiv:1307.0007 were based on the
   /// largest mt, but this only makes a difference for values of the
   /// symmetry_cut close to 1/2).
   ///
   /// If the (optional) pileup subtractor can be supplied, then see
   /// also the documentation for the set_input_jet_is_subtracted() member
   /// function.
   ///
   /// NB: The configuration of MMDT provided by this constructor is
   /// probably the most robust for use with subtraction.
   ModifiedMassDropTagger(double symmetry_cut, 
                          const FunctionOfPseudoJet<PseudoJet> * subtractor = 0
                          ) :
     RecursiveSymmetryCutBase(scalar_z,  // the default SymmetryMeasure
                              std::numeric_limits<double>::infinity(), // the default is no mass drop
                              larger_pt, // the default RecursionChoice
                              subtractor),
     _symmetry_cut(symmetry_cut)
   {}
 
   /// Full constructor, which takes the following parameters:
   ///
   /// \param symmetry_cut       the value of the cut on the symmetry measure
   /// \param symmetry_measure   the choice of measure to use to estimate the symmetry
   /// \param mu_cut             the maximal allowed value of mass drop variable mu = m_heavy/m_parent 
   /// \param recursion_choice   the strategy used to decide which subjet to recurse into
   /// \param subtractor         an optional pointer to a pileup subtractor (ignored if zero)
   ///
   /// To obtain the mMDT as discussed in arXiv:1307.0007, use an
   /// symmetry_measure that's one of the following
   ///
   /// - RecursiveSymmetryCutBase::y         (for a cut on y)
   /// - RecursiveSymmetryCutBase::scalar_z  (for a cut on z)
   ///
   /// and use the default recursion choice of
   /// RecursiveSymmetryCutBase::larger_pt (larger_mt will give something
   /// very similar, while larger_m will give the behaviour of the
   /// original, but now deprecated MassDropTagger)
   ///
   /// Notes: 
   ///
   /// - By default the ModifiedMassDropTagger will relcuster the jets
   ///   with the C/A algorithm (if needed).
   ///
   /// - the mu_cut parameter is mostly irrelevant when it's taken
   ///   larger than about 1/2: the tagger is then one that cuts
   ///   essentially on the (a)symmetry of the jet's momentum
   ///   sharing. The default value of infinity turns off its use
   ///   entirely
   ModifiedMassDropTagger(double           symmetry_cut, 
                          SymmetryMeasure  symmetry_measure,
                          double           mu_cut = std::numeric_limits<double>::infinity(), 
                          RecursionChoice  recursion_choice = larger_pt,
                          const FunctionOfPseudoJet<PseudoJet> * subtractor = 0
                          ) : 
     RecursiveSymmetryCutBase(symmetry_measure, mu_cut, recursion_choice, subtractor),
     _symmetry_cut(symmetry_cut)
   {}
 
   /// default destructor
   virtual ~ModifiedMassDropTagger(){}
 
   //----------------------------------------------------------------------
   // access to class info
   double symmetry_cut() const { return _symmetry_cut; }
   
 protected:
 
   /// The symmetry cut function for MMDT returns just a constant, since the cut value
   /// has no dependence on the subjet kinematics
   virtual double symmetry_cut_fn(const PseudoJet & /* p1 */, 
                                  const PseudoJet & /* p2 */,
                                  void *extra_parameters = 0
                                  ) const {return _symmetry_cut;}
   virtual std::string symmetry_cut_description() const;
 
   double           _symmetry_cut;
 };
 
 } // namespace contrib
 
 FASTJET_END_NAMESPACE
 
 #endif  // __FASTJET_CONTRIB_MODIFIEDMASSDROPTAGGER_HH__

This page was automatically generated by the 2.3.7 LXR engine. The LXR team