Rivet analyses
Measurement of ATLAS track jet properties at 7 TeV
Experiment: ATLAS (LHC)
Inspire ID: 919017
Status: VALIDATED
Authors: - Seth Zenz - Andy Buckley
References: - Expt page: ATLAS-STDM-2010-14 - Phys.Rev.D 84 (2011) 054001 - DOI: 10.1103/PhysRevD.84.054001 - arXiv: 1107.3311 - Expt page: ATLAS-STDM-2010-14 - CERN-PH-EP-2011-110
Beams: p+ p+
Beam energies: (3500.0, 3500.0)GeV
Run details: - Min bias QCD at 7 TeV.
ATLAS measurement of track jet pT, multiplicity per jet, longitudinal fragmentation, transverse momentum, radius w.r.t jet axis distributions, with jets constructed from charged tracks with pT > 300 MeV, using the anti-kT jet algorithm with R = 0.4, 0.6.
Source
code:ATLAS_2011_I919017.cc
// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/ChargedFinalState.hh"
#include "Rivet/Projections/FastJets.hh"
namespace Rivet {
namespace {
inline double calcz(const Jet& j, const Particle& p) {
const double num = j.p3().dot(p.p3());
const double den = j.p3().mod2();
return min(num/den, 0.999999);
}
inline double calcptrel(const Jet& j, const Particle& p) {
const double num = j.p3().cross(p.p3()).mod();
const double den = j.p3().mod();
return num/den;
}
inline double calcr(const Jet& j, const Particle& p) {
return deltaR(j.rapidity(), j.phi(), p.rapidity(), p.phi());
}
// For annulus area kludge
/// @todo Improve somehow... need normalisation *without* bin width factors!
inline double calcrweight(const Jet& j, const Particle& p) {
size_t nBins_r = 26;
double bins_r[] = { 0.00, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10,
0.12, 0.14, 0.16, 0.18, 0.20, 0.22, 0.24, 0.26, 0.28, 0.30,
0.35, 0.40, 0.45, 0.50, 0.55, 0.60 };
double r = calcr(j,p);
for (size_t bin = 0 ; bin < nBins_r ; bin++) {
if (r < bins_r[bin+1]) {
double up = bins_r[bin+1];
double down = bins_r[bin];
return ((up-down)/(M_PI*(up*up-down*down)));
}
}
return 1.0;
}
}
class ATLAS_2011_I919017 : public Analysis {
public:
/// @name Constructors etc.
/// @{
/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(ATLAS_2011_I919017);
/// @}
public:
/// @name Analysis methods
/// @{
/// Book histograms and initialise projections before the run
void init() {
ChargedFinalState cfs((Cuts::etaIn(-2.5, 2.5) && Cuts::pT >= 0.3*GeV));
FastJets trkjets04(cfs, JetAlg::ANTIKT, 0.4);
FastJets trkjets06(cfs, JetAlg::ANTIKT, 0.6);
declare(trkjets04, "Jets04");
declare(trkjets06, "Jets06");
// Book histograms
const vector<string> rapbins{"00_05_", "05_10_", "10_15_", "15_19_"};
const vector<string> ptbins{"04_06", "06_10", "10_15", "15_24", "24_40"};
for (const string R : {"04_", "06_"}) {
size_t iy = (R == "04_")? 1 : 2;
book(_c[R+"sumw"], "/TMP/"+R+"sumw");
size_t irap = 0;
for (const string& rapbin : rapbins) {
++irap;
book(_hinc[R+rapbin], irap, 1, iy);
size_t ipt = 0;
for (const string& ptbin : ptbins) {
++ipt;
const string suff = R + rapbin + ptbin;
if (irap == 1) {
size_t offset = rapbins.size();
book(_h["N"+R+"00_19_"+ptbin], offset+ipt, 1, iy);
offset += ptbins.size()*ptbins.size();
book(_h["z"+R+"00_19_"+ptbin], offset+ipt, 1, iy);
offset += ptbins.size()*ptbins.size();
book(_h["ptrel"+R+"00_19_"+ptbin], offset+ipt, 1, iy);
offset += ptbins.size()*ptbins.size();
book(_h["rdA"+R+"00_19_"+ptbin], offset+ipt, 1, iy);
book(_c["numjets"+R+"00_19_"+ptbin], "/TMP/numjets"+R+"00_19_"+ptbin);
}
size_t offset = rapbins.size() + irap*ptbins.size();
book(_h["N"+suff], offset+ipt, 1, iy);
offset = rapbins.size() + (irap+ptbins.size())*ptbins.size();
book(_h["z"+suff], offset+ipt, 1, iy);
offset = rapbins.size() + (irap+2*ptbins.size())*ptbins.size();
book(_h["ptrel"+suff], offset+ipt, 1, iy);
offset = rapbins.size() + (irap+3*ptbins.size())*ptbins.size();
book(_h["rdA"+suff], offset+ipt, 1, iy);
book(_c["numjets"+suff], "/TMP/numjets"+suff);
}
}
}
}
/// Perform the per-event analysis
void analyze(const Event& event) {
doCollection("04", event);
doCollection("06", event);
}
void doCollection(const string& Rval, const Event& event) {
const Jets& jets = apply<JetFinder>(event, "Jets"+Rval).jets();
if (jets.empty()) return;
const string R = Rval+"_";
_c[R+"sumw"]->fill();
for (const Jet& j : jets) {
const double jetpt = j.pT()/GeV;
const double jetrap = j.absrap();
string rapbin, ptbin;
if (jetrap >= 1.9) continue;
if (jetrap < 0.5) rapbin = "00_05_";
else if (jetrap < 1.0) rapbin = "05_10_";
else if (jetrap < 1.5) rapbin = "10_15_";
else rapbin = "15_19_";
_hinc[R+rapbin]->fill(jetpt);
if (inRange(jetpt, 4., 6.)) ptbin = "04_06";
else if (inRange(jetpt, 6., 10.)) ptbin = "06_10";
else if (inRange(jetpt, 10., 15.)) ptbin = "10_15";
else if (inRange(jetpt, 15., 24.)) ptbin = "15_24";
else if (inRange(jetpt, 24., 40.)) ptbin = "24_40";
else continue;
fillgroup(j, R+"00_19_"+ptbin);
fillgroup(j, R+rapbin+ptbin);
} // each jet
}
void fillgroup(const Jet& j, const string& suff) {
_c["numjets"+suff]->fill();
_h["N"+suff]->fill(j.particles().size());
for (const Particle& p : j.particles()) {
_h["z"+suff]->fill(calcz(j, p));
_h["ptrel"+suff]->fill(calcptrel(j, p));
_h["rdA"+suff]->fill(calcr(j, p), calcrweight(j, p));
}
}
/// Normalise histograms etc., after the run
void finalize() {
const double xsec = crossSection()/microbarn;
for (auto& item : _hinc) {
if (item.first.substr(0,2) == "04") {
double sf = _c["04_sumw"]->val();
if (item.first.substr(3,2) == "15") sf *= 0.8;
if (sf) scale(item.second, xsec/sf);
else normalize(item.second, 0.0);
}
else {
double sf = _c["06_sumw"]->val();
if (item.first.substr(3,2) == "15") sf *= 0.8;
if (sf) scale(item.second, xsec/sf);
else normalize(item.second, 0.0);
}
}
for (auto& item : _h) {
const string suff = item.first.substr(item.first.size()-14);
const double sf = _c["numjets"+suff]->val();
if (sf) scale(item.second, 1.0/sf);
else normalize(item.second, 0.0);
}
}
/// @}
private:
/// @name Histograms
/// @{
map<string,CounterPtr> _c;
map<string,Histo1DPtr> _h, _hinc;
/// @}
};
RIVET_DECLARE_PLUGIN(ATLAS_2011_I919017);
}