2 ///////////////////////////////////////////////////////////////////////////////
4 // Description: header file for the computation of jet area //
5 // This file is part of the SISCone project. //
6 // For more details, see http://projects.hepforge.org/siscone //
8 // Copyright (c) 2006 Gavin Salam and Gregory Soyez //
10 // This program is free software; you can redistribute it and/or modify //
11 // it under the terms of the GNU General Public License as published by //
12 // the Free Software Foundation; either version 2 of the License, or //
13 // (at your option) any later version. //
15 // This program is distributed in the hope that it will be useful, //
16 // but WITHOUT ANY WARRANTY; without even the implied warranty of //
17 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the //
18 // GNU General Public License for more details. //
20 // You should have received a copy of the GNU General Public License //
21 // along with this program; if not, write to the Free Software //
22 // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA //
24 // $Revision:: 149 $//
25 // $Date:: 2007-03-15 00:13:58 +0100 (Thu, 15 Mar 2007) $//
26 ///////////////////////////////////////////////////////////////////////////////
28 #ifndef __SISCONE_AREA_H__
29 #define __SISCONE_AREA_H__
38 * real Jet information, including its area(s)
40 * This class contains information for one single jet.
41 * That is, first, its momentum carrying information
42 * about its centre and pT, and second, its particle
44 * Compared to the Cjet class, it also includes the
45 * passive and active areas of the jet computed using
48 class Cjet_area : public Cjet{
53 /// jet-initialised ctor
60 double passive_area; ///< passive area
61 double active_area; ///< active area
66 * class for the computation of jet areas.
68 * This is the class user should use whenever you want to compute
69 * the jet area (passive and active). .
70 * It uses the SISCone algorithm to perform the jet analysis.
72 class Carea : public Csiscone{
81 * compute the jet areas from a given particle set.
82 * The parameters of this method are the ones which control the jet clustering alghorithn.
83 * Note that the pt_min is not allowed here soince the jet-area determination involves soft
84 * particles/jets and thus is used internally.
85 * \param _particles list of particles
86 * \param _radius cone radius
87 * \param _f shared energy threshold for splitting&merging
88 * \param _n_pass_max maximum number of passes (0=full search, the default)
89 * \param _split_merge_scale the scale choice for the split-merge procedure
90 * NOTE: SM_pt leads to IR unsafety for some events with momentum conservation.
91 * SM_Et is IR safe but not boost invariant and not implemented(!)
92 * SM_mt is IR safe for hadronic events, but not for decays of two
93 * back-to-back particles of identical mass
95 * is always IR safe, and also boost invariant (default)
96 * \param _hard_only when this is set on, only hard jets are computed
97 * and not the purely ghosted jets (default: false)
98 * \return the number of jets (including pure-ghost ones if they are included)
100 int compute_areas(std::vector<Cmomentum> &_particles, double _radius, double _f,
101 int _n_pass_max=0, Esplit_merge_scale _split_merge_scale=SM_pttilde,
102 bool _hard_only=false);
105 * compute the jet active areas from a given particle set.
106 * The parameters of this method are the ones which control the jet clustering alghorithn.
107 * Note that the pt_min is not allowed here soince the jet-area determination involves soft
108 * particles/jets and thus is used internally.
109 * See compute_areas for paramters definition.
110 * \return the number of jets (including pure-ghost ones if they are included)
112 int compute_active_areas(std::vector<Cmomentum> &_particles, double _radius, double _f,
113 int _n_pass_max=0, Esplit_merge_scale _split_merge_scale=SM_pttilde,
114 bool _hard_only=false);
117 * compute the jet passive areas from a given particle set.
118 * The parameters of this method are the ones which control the jet clustering alghorithn.
119 * Note that the pt_min is not allowed here soince the jet-area determination involves soft
120 * particles/jets and thus is used internally.
121 * See compute_areas for paramters definition.
123 int compute_passive_areas(std::vector<Cmomentum> &_particles, double _radius, double _f,
124 int _n_pass_max=0, Esplit_merge_scale _split_merge_scale=SM_pttilde);
126 int grid_size; ///< size of the grid we add soft particles on (N_soft=(grid_size^2))
127 double grid_eta_max; ///< maximal value of eta we add soft particles on
128 double grid_shift; ///< fractional (random) displacement of the points om the grid
130 double pt_soft; ///< pt of the soft particles added
131 double pt_shift; ///< amplitude of the pt random shift
132 double pt_soft_min; ///< pt_min used in SM to compute passive areas
134 /// jets with their areas
135 std::vector<Cjet_area> jet_areas;