[code]// main05.cc is a part of the PYTHIA event generator.
// Copyright © 2014 Torbjorn Sjostrand.
// PYTHIA is licenced under the GNU GPL version 2, see COPYING for details.
// Please respect the MCnet Guidelines, see GUIDELINES for details.
// This is a simple test program.
// It studies jet production at the LHC, using SlowJet and CellJet.
// Note: the two finders are intended to construct approximately the same
// jet properties, but provides output in slightly different format,
// and have here not been optimized to show maximum possible agreement.
#include “TH1.h”
#include “TVirtualPad.h”
#include “TApplication.h”
// ROOT, for saving file.
#include “TFile.h”
#include "Pythia8/Pythia.h"
using namespace Pythia8;
int main(int argc, char* argv[]) {
// Create the ROOT application environment.
TApplication theApp(“hist”, &argc, argv);
// Create file on which histogram(s) can be saved.
TFile* outFile = new TFile(“hist.root”, “RECREATE”);
// Book histogram.
TH1F *hist1 = new TH1F(“eTdiffC”,“eT difference between jets”, 100, -0.5, 799.5);
// Number of events, generated and listed ones.
int nEvent = 500;
int nListJets = 2;
// Generator. LHC process and output selection. Initialization.
Pythia pythia;
pythia.readString(“Beams:frameType = 4”);
pythia.readString("ProcessLevel:all = off");
pythia.readString("Beams:LHEF=unweighted_events.lhe");
// pythia.readString(“Beams:eCM = 14000.”);
//pythia.readString(“HardQCD:all = on”);
pythia.readString(“PhaseSpace:pTHatMin = 200.”);
pythia.readString(“Next:numberShowInfo = 0”);
pythia.readString(“Next:numberShowProcess = 0”);
pythia.readString(“Next:numberShowEvent = 0”);
pythia.init();
// Common parameters for the two jet finders.
double etaMax = 25.;
double radius = 0.7;
double pTjetMin = 10.;
// Exclude neutrinos (and other invisible) from study.
int nSel = 1;
// Range and granularity of CellJet jet finder.
int nEta = 80;
int nPhi = 64;
// Set up SlowJet jet finder, with anti-kT clustering
// and pion mass assumed for non-photons…
SlowJet slowJet( -1, radius, pTjetMin, etaMax, nSel, 1);
// Set up CellJet jet finder.
CellJet cellJet( etaMax, nEta, nPhi, nSel);
// Histograms. Note similarity in names, even when the two jet finders
// do not calculate identically the same property (pT vs. ET, y vs. eta).
Hist nJetsS(“number of jets, SlowJet”, 50, -0.5, 49.5);
Hist nJetsC(“number of jets, CellJet”, 50, -0.5, 49.5);
Hist nJetsD(“number of jets, CellJet - SlowJet”, 45, -22.5, 22.5);
Hist eTjetsS(“pT for jets, SlowJet”, 100, 0., 500.);
Hist eTjetsC(“eT for jets, CellJet”, 100, 0., 500.);
Hist etaJetsS(“y for jets, SlowJet”, 100, -5., 5.);
Hist etaJetsC(“eta for jets, CellJet”, 100, -5., 5.);
Hist phiJetsS(“phi for jets, SlowJwt”, 100, -M_PI, M_PI);
Hist phiJetsC(“phi for jets, CellJet”, 100, -M_PI, M_PI);
Hist distJetsS(“R distance between jets, SlowJet”, 100, 0., 10.);
Hist distJetsC(“R distance between jets, CellJet”, 100, 0., 10.);
Hist eTdiffS(“pT difference, SlowJet”, 100, -100., 400.);
//Hist eTdiffC(“eT difference, CellJet”, 100, -100., 400.);
// Begin event loop. Generate event. Skip if error.
for (int iEvent = 0; iEvent < nEvent; ++iEvent) {
if (!pythia.next()) continue;
// Analyze Slowet jet properties. List first few.
slowJet. analyze( pythia.event );
if (iEvent < nListJets) slowJet.list();
// Fill SlowJet inclusive jet distributions.
nJetsS.fill( slowJet.sizeJet() );
for (int i = 0; i < slowJet.sizeJet(); ++i) {
eTjetsS.fill( slowJet.pT(i) );
etaJetsS.fill( slowJet.y(i) );
phiJetsS.fill( slowJet.phi(i) );
}
// Fill SlowJet distance between jets.
for (int i = 0; i < slowJet.sizeJet() - 1; ++i)
for (int j = i +1; j < slowJet.sizeJet(); ++j) {
double dEta = slowJet.y(i) - slowJet.y(j);
double dPhi = abs( slowJet.phi(i) - slowJet.phi(j) );
if (dPhi > M_PI) dPhi = 2. * M_PI - dPhi;
double dR = sqrt( pow2(dEta) + pow2(dPhi) );
distJetsS.fill( dR );
}
// Fill SlowJet pT-difference between jets (to check ordering of list).
for (int i = 1; i < slowJet.sizeJet(); ++i)
eTdiffS.fill( slowJet.pT(i-1) - slowJet.pT(i) );
// Analyze CellJet jet properties. List first few.
cellJet. analyze( pythia.event, pTjetMin, radius );
if (iEvent < nListJets) cellJet.list();
// Fill CellJet inclusive jet distributions.
nJetsC.fill( cellJet.size() );
for (int i = 0; i < cellJet.size(); ++i) {
eTjetsC.fill( cellJet.eT(i) );
etaJetsC.fill( cellJet.etaWeighted(i) );
phiJetsC.fill( cellJet.phiWeighted(i) );
}
// Fill CellJet distance between jets.
for (int i = 0; i < cellJet.size() - 1; ++i)
for (int j = i +1; j < cellJet.size(); ++j) {
double dEta = cellJet.etaWeighted(i)
- cellJet.etaWeighted(j);
double dPhi = abs( cellJet.phiWeighted(i)
- cellJet.phiWeighted(j) );
if (dPhi > M_PI) dPhi = 2. * M_PI - dPhi;
double dR = sqrt( pow2(dEta) + pow2(dPhi) );
distJetsC.fill( dR );
}
// Fill CellJet ET-difference between jets (to check ordering of list).
for (int i = 1; i < cellJet.size(); ++i)
hist1->Fill( cellJet.eT(i-1) - cellJet.eT(i) );
// Compare number of jets for the two finders.
nJetsD.fill( cellJet.size() - slowJet.sizeJet() );
// End of event loop. Statistics. Histograms.
}
pythia.stat();
cout << nJetsS << nJetsC<< eTjetsC<< eTjetsS
<< etaJetsS << etaJetsC << phiJetsS << phiJetsC
<< distJetsS << distJetsC << eTdiffS;
// Show histogram. Possibility to close it.
//eTdiffC -> Draw();
std::cout << “\nDouble click on the histogram window to quit.\n”;
gPad->WaitPrimitive();
// Save histogram on file and close file.
// -> Write();
//delete outFile;
// Done.
return 0;
}[/code]
i am getting the following error:
Double click on the histogram window to quit.
*** Break *** segmentation violation