Skip to content
Snippets Groups Projects
Commit 7bde2666 authored by Whitney Armstrong's avatar Whitney Armstrong
Browse files

modified: dis/src/pythia_dis.cc

parent 58fb453c
Branches
Tags
No related merge requests found
Hide whitespace changes
Inline Side-by-side
Showing
with 34 additions and 111 deletions
dis/src/pythia_dis.cc
+ 34
− 111
View file @ 7bde2666
<<<<<<< HEAD
// main45.cc is a part of the PYTHIA event generator.
// Copyright (C) 2020 Torbjorn Sjostrand.
// PYTHIA is licenced under the GNU GPL v2 or later, see COPYING for details.
// Please respect the MCnet Guidelines, see GUIDELINES for details.
// Author: Stefan Prestel <stefan.prestel@thep.lu.se>.
// Keywords: LHE file; hepmc;
// This program (main45.cc) illustrates how a file with HepMC3 events can be
// generated by Pythia8. See main44.cc for how to ouput HepMC2 events instead.
// Note: both main44.cc and main45.cc can use the same main44.cmnd input card.
#include "Pythia8/Pythia.h"
#include "Pythia8Plugins/HepMC3.h"
#include <unistd.h>
using namespace Pythia8;
//==========================================================================
// Example main programm to illustrate merging.
int main( int argc, char* argv[] ){
// Check that correct number of command-line arguments
if (argc != 2) {
cerr << " Unexpected number of command-line arguments ("<<argc<<"). \n"
<< " You are expected to provide the arguments" << endl
<< " 1. Output file for HepMC events" << endl
<< " Program stopped. " << endl;
return 1;
}
// Beam energies, minimal Q2, number of events to generate.
double eProton = 250.;
double eElectron = 10.0;
double Q2min = 5.;
int nEvent = 10000;
=======
#include "Pythia8/Pythia.h"
#include "Pythia8Plugins/HepMC3.h"
#include <unistd.h>
......@@ -147,13 +106,11 @@ int main(int argc, char* argv[]) {
return 0;
}
// Beam energies, minimal Q2, number of events to generate.
// Beam energies, minimal Q2, number of events to generate.
double eProton = s.E_ion;
double eElectron = s.E_electron;
double Q2min = s.Q2_min;
int nEvent = s.N_events;
>>>>>>> 5c96bf0c8bedda31e7d1c8a8f1d24ceb5722db3a
// Generator. Shorthand for event.
Pythia pythia;
......@@ -162,11 +119,7 @@ int main(int argc, char* argv[]) {
// Set up incoming beams, for frame with unequal beam energies.
pythia.readString("Beams:frameType = 2");
// BeamA = proton.
<<<<<<< HEAD
pythia.readString("Beams:idA = 2212");
=======
pythia.readString("Beams:idA = " +std::to_string(s.ion_PID));
>>>>>>> 5c96bf0c8bedda31e7d1c8a8f1d24ceb5722db3a
pythia.readString("Beams:idA = " + std::to_string(s.ion_PID));
pythia.settings.parm("Beams:eA", eProton);
// BeamB = electron.
pythia.readString("Beams:idB = 11");
......@@ -176,11 +129,7 @@ int main(int argc, char* argv[]) {
// Neutral current (with gamma/Z interference).
pythia.readString("WeakBosonExchange:ff2ff(t:gmZ) = on");
// Uncomment to allow charged current.
<<<<<<< HEAD
//pythia.readString("WeakBosonExchange:ff2ff(t:W) = on");
=======
// pythia.readString("WeakBosonExchange:ff2ff(t:W) = on");
>>>>>>> 5c96bf0c8bedda31e7d1c8a8f1d24ceb5722db3a
// Phase-space cut: minimal Q2 of process.
pythia.settings.parm("PhaseSpace:Q2Min", Q2min);
......@@ -205,23 +154,6 @@ int main(int argc, char* argv[]) {
cout << endl << endl << endl;
// Histograms.
<<<<<<< HEAD
double Wmax = sqrt(4.* eProton * eElectron);
Hist Qhist("Q [GeV]", 100, 0., 50.);
Hist Whist("W [GeV]", 100, 0., Wmax);
Hist xhist("x", 100, 0., 1.);
Hist yhist("y", 100, 0., 1.);
Hist pTehist("pT of scattered electron [GeV]", 100, 0., 50.);
Hist pTrhist("pT of radiated parton [GeV]", 100, 0., 50.);
Hist pTdhist("ratio pT_parton/pT_electron", 100, 0., 5.);
double sigmaTotal(0.), errorTotal(0.);
bool wroteRunInfo = false;
// Get the inclusive x-section by summing over all process x-sections.
double xs = 0.;
for (int i=0; i < pythia.info.nProcessesLHEF(); ++i)
xs += pythia.info.sigmaLHEF(i);
=======
double Wmax = sqrt(4. * eProton * eElectron);
Hist Qhist("Q [GeV]", 100, 0., 50.);
Hist Whist("W [GeV]", 100, 0., Wmax);
......@@ -235,13 +167,14 @@ int main(int argc, char* argv[]) {
bool wroteRunInfo = false;
// Get the inclusive x-section by summing over all process x-sections.
double xs = 0.;
for (int i = 0; i < pythia.info.nProcessesLHEF(); ++i)
for (int i = 0; i < pythia.info.nProcessesLHEF(); ++i) {
xs += pythia.info.sigmaLHEF(i);
>>>>>>> 5c96bf0c8bedda31e7d1c8a8f1d24ceb5722db3a
}
// Begin event loop.
for (int iEvent = 0; iEvent < nEvent; ++iEvent) {
if (!pythia.next()) continue;
if (!pythia.next())
continue;
double sigmaSample = 0., errorSample = 0.;
......@@ -252,35 +185,37 @@ int main(int argc, char* argv[]) {
Vec4 pPhoton = peIn - peOut;
// Q2, W2, Bjorken x, y.
double Q2 = - pPhoton.m2Calc();
double W2 = (pProton + pPhoton).m2Calc();
double x = Q2 / (2. * pProton * pPhoton);
double y = (pProton * pPhoton) / (pProton * peIn);
double Q2 = -pPhoton.m2Calc();
double W2 = (pProton + pPhoton).m2Calc();
double x = Q2 / (2. * pProton * pPhoton);
double y = (pProton * pPhoton) / (pProton * peIn);
// Fill kinematics histograms.
Qhist.fill( sqrt(Q2) );
Whist.fill( sqrt(W2) );
xhist.fill( x );
yhist.fill( y );
pTehist.fill( event[6].pT() );
Qhist.fill(sqrt(Q2));
Whist.fill(sqrt(W2));
xhist.fill(x);
yhist.fill(y);
pTehist.fill(event[6].pT());
// pT spectrum of partons being radiated in shower.
for (int i = 0; i < event.size(); ++i) if (event[i].statusAbs() == 43) {
pTrhist.fill( event[i].pT() );
pTdhist.fill( event[i].pT() / event[6].pT() );
}
for (int i = 0; i < event.size(); ++i)
if (event[i].statusAbs() == 43) {
pTrhist.fill(event[i].pT());
pTdhist.fill(event[i].pT() / event[6].pT());
}
// Get event weight(s).
double evtweight = pythia.info.weight();
double evtweight = pythia.info.weight();
// Do not print zero-weight events.
if ( evtweight == 0. ) continue;
if (evtweight == 0.)
continue;
// Create a GenRunInfo object with the necessary weight names and write
// them to the HepMC3 file only once.
if (!wroteRunInfo) {
shared_ptr<HepMC3::GenRunInfo> genRunInfo;
genRunInfo = make_shared<HepMC3::GenRunInfo>();
genRunInfo = make_shared<HepMC3::GenRunInfo>();
vector<string> weight_names = pythia.info.weightNameVector();
genRunInfo->set_weight_names(weight_names);
ascii_io.set_run_info(genRunInfo);
......@@ -288,52 +223,40 @@ int main(int argc, char* argv[]) {
wroteRunInfo = true;
}
// Construct new empty HepMC event.
HepMC3::GenEvent hepmcevt;
// Work with weighted (LHA strategy=-4) events.
double normhepmc = 1.;
if (abs(pythia.info.lhaStrategy()) == 4)
normhepmc = 1. / double(1e9*nEvent);
normhepmc = 1. / double(1e9 * nEvent);
// Work with unweighted events.
else
normhepmc = xs / double(1e9*nEvent);
normhepmc = xs / double(1e9 * nEvent);
// Set event weight
//hepmcevt.weights().push_back(evtweight*normhepmc);
// hepmcevt.weights().push_back(evtweight*normhepmc);
// Fill HepMC event
toHepMC.fill_next_event( pythia, &hepmcevt );
toHepMC.fill_next_event(pythia, &hepmcevt);
// Add the weight of the current event to the cross section.
sigmaTotal += evtweight*normhepmc;
sigmaSample += evtweight*normhepmc;
errorTotal += pow2(evtweight*normhepmc);
errorSample += pow2(evtweight*normhepmc);
sigmaTotal += evtweight * normhepmc;
sigmaSample += evtweight * normhepmc;
errorTotal += pow2(evtweight * normhepmc);
errorSample += pow2(evtweight * normhepmc);
// Report cross section to hepmc
shared_ptr<HepMC3::GenCrossSection> xsec;
xsec = make_shared<HepMC3::GenCrossSection>();
// First add object to event, then set cross section. This order ensures
// that the lengths of the cross section and the weight vector agree.
hepmcevt.set_cross_section( xsec );
xsec->set_cross_section( sigmaTotal*1e9, pythia.info.sigmaErr()*1e9 );
hepmcevt.set_cross_section(xsec);
xsec->set_cross_section(sigmaTotal * 1e9, pythia.info.sigmaErr() * 1e9);
// Write the HepMC event to file. Done with it.
ascii_io.write_event(hepmcevt);
<<<<<<< HEAD
=======
>>>>>>> 5c96bf0c8bedda31e7d1c8a8f1d24ceb5722db3a
// End of event loop. Statistics and histograms.
}
pythia.stat();
cout << Qhist << Whist << xhist << yhist << pTehist << pTrhist << pTdhist;
return 0;
<<<<<<< HEAD
}
=======
}
>>>>>>> 5c96bf0c8bedda31e7d1c8a8f1d24ceb5722db3a
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Please register or to comment