| 1 | // $Id: SoftDrop.cc 686 2014-06-14 03:25:09Z jthaler $
|
|---|
| 2 | //
|
|---|
| 3 | // Copyright (c) 2014-, Gregory Soyez, Jesse. Thaler
|
|---|
| 4 | // based on arXiv:1402.2657 by Andrew J. Larkoski, Simone Marzani,
|
|---|
| 5 | // Gregory Soyez, Jesse Thaler
|
|---|
| 6 | //
|
|---|
| 7 | //----------------------------------------------------------------------
|
|---|
| 8 | // This file is part of FastJet contrib.
|
|---|
| 9 | //
|
|---|
| 10 | // It is free software; you can redistribute it and/or modify it under
|
|---|
| 11 | // the terms of the GNU General Public License as published by the
|
|---|
| 12 | // Free Software Foundation; either version 2 of the License, or (at
|
|---|
| 13 | // your option) any later version.
|
|---|
| 14 | //
|
|---|
| 15 | // It is distributed in the hope that it will be useful, but WITHOUT
|
|---|
| 16 | // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
|---|
| 17 | // or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
|
|---|
| 18 | // License for more details.
|
|---|
| 19 | //
|
|---|
| 20 | // You should have received a copy of the GNU General Public License
|
|---|
| 21 | // along with this code. If not, see <http://www.gnu.org/licenses/>.
|
|---|
| 22 | //----------------------------------------------------------------------
|
|---|
| 23 |
|
|---|
| 24 | #include "SoftDrop.hh"
|
|---|
| 25 | #include <cmath>
|
|---|
| 26 | #include <sstream>
|
|---|
| 27 |
|
|---|
| 28 | using namespace std;
|
|---|
| 29 |
|
|---|
| 30 | FASTJET_BEGIN_NAMESPACE // defined in fastjet/internal/base.hh
|
|---|
| 31 |
|
|---|
| 32 | namespace contrib{
|
|---|
| 33 |
|
|---|
| 34 | //----------------------------------------------------------------------
|
|---|
| 35 | // TODO:
|
|---|
| 36 | //
|
|---|
| 37 | // - implement reclustering (at the moment we assume it's C/A as for mMDT
|
|---|
| 38 | //
|
|---|
| 39 | // - what is returned if no substructure is found? [and for negativeve
|
|---|
| 40 | // pt, m2 or other situations where mMDT currentlty returns an empty
|
|---|
| 41 | // PseudoJet]
|
|---|
| 42 | //
|
|---|
| 43 | // GS.: mMDT seeks substructure so it makes sense for it to return
|
|---|
| 44 | // an empry PseudoJet when no substructure is found (+ it is the
|
|---|
| 45 | // original behaviour). For SoftDrop, in grooming mode (beta>0), if
|
|---|
| 46 | // would make sense to return a jet with a single particle. In
|
|---|
| 47 | // tagging mode (beta<0), the situation is less clear. At the level
|
|---|
| 48 | // of the implementation, having a virtual function could work
|
|---|
| 49 | // (with a bit of care to cover the -ve pt or m2 cases)
|
|---|
| 50 | //
|
|---|
| 51 | // - Do we include Andrew and Simone in the "contrib-author" list
|
|---|
| 52 | // since they are on the paper? Do we include Gavin in the author's
|
|---|
| 53 | // list since he started this contrib?
|
|---|
| 54 | //
|
|---|
| 55 | //----------------------------------------------------------------------
|
|---|
| 56 |
|
|---|
| 57 | //----------------------------------------------------------------------
|
|---|
| 58 | double SoftDrop::symmetry_cut_fn(const PseudoJet & p1,
|
|---|
| 59 | const PseudoJet & p2) const{
|
|---|
| 60 | return _symmetry_cut * pow(p1.squared_distance(p2)/_R0sqr, 0.5*_beta);
|
|---|
| 61 | }
|
|---|
| 62 |
|
|---|
| 63 | //----------------------------------------------------------------------
|
|---|
| 64 | string SoftDrop::symmetry_cut_description() const {
|
|---|
| 65 | ostringstream ostr;
|
|---|
| 66 | ostr << _symmetry_cut << " (theta/" << sqrt(_R0sqr) << ")^" << _beta << " [SoftDrop]";
|
|---|
| 67 | return ostr.str();
|
|---|
| 68 | }
|
|---|
| 69 |
|
|---|
| 70 | } // namespace contrib
|
|---|
| 71 |
|
|---|
| 72 | FASTJET_END_NAMESPACE
|
|---|
