main26
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// main26.cc is a part of the PYTHIA event generator.
// Copyright (C) 2024 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.
// Authors:
// Stefan Ask
// Contact: Nishita Desai <nishita.desai@tifr.res.in>
// Keywords:
// Extra dimensions
// BSM
// This is a test program for the extra dimensions processes.
// Documentation: S. Ask et al., arXiv:0809.4750 and arXiv:0912.4233
#include "Pythia8/Pythia.h"
using namespace Pythia8;
// The main program.
int main() {
// Test cases
// 1 = Jet + G (real G emission)
// 2 = Jet + U (real U emission)
// 3 = Z + G (real G emission)
// 4 = Z + U (real U emission)
// 5 = gamma gamma (LED G* exchange)
// 6 = l lbar (LED U* exchange).
// Note: charged leptons only!
// 7 = Z_KK/gamma_KK (TEV ED resonance)
// 8 = G* (RS resonance, SM on the TeV brane)
// 9 = kk-gluon* (RS resonance)
int nTest = 1;
// Number of events to generate. Max number of errors.
int nEvent = 1000;
int nAbort = 50;
// Pythia generator.
Pythia pythia;
// PYTHIA paramters:
pythia.readString("PhaseSpace:showViolation = off");
// Test case parameters
if (nTest == 1) {
pythia.readString("ExtraDimensionsLED:monojet = on");
pythia.readString("ExtraDimensionsLED:n = 4");
pythia.readString("ExtraDimensionsLED:MD = 4000.");
pythia.readString("ExtraDimensionsLED:CutOffmode = 3");
pythia.readString("ExtraDimensionsLED:t = 2");
pythia.readString("5000039:m0 = 2500.");
pythia.readString("5000039:mWidth = 1500.");
pythia.readString("5000039:mMin = 1.");
pythia.readString("5000039:mMax = 13990.");
pythia.readString("PhaseSpace:pTHatMin = 700.");
} else if (nTest == 2){
pythia.readString("ExtraDimensionsUnpart:gg2Ug = off");
pythia.readString("ExtraDimensionsUnpart:qg2Uq = on");
pythia.readString("ExtraDimensionsUnpart:qqbar2Ug = on");
pythia.readString("ExtraDimensionsUnpart:spinU = 1");
pythia.readString("ExtraDimensionsUnpart:dU = 1.2");
pythia.readString("ExtraDimensionsUnpart:LambdaU = 1000");
pythia.readString("ExtraDimensionsUnpart:lambda = 1.0");
pythia.readString("ExtraDimensionsUnpart:CutOffmode = 0");
pythia.readString("5000039:m0 = 300.");
pythia.readString("5000039:mWidth = 500.");
pythia.readString("5000039:mMin = 1.");
pythia.readString("5000039:mMax = 13990.");
pythia.readString("PhaseSpace:pTHatMin = 700.");
} else if (nTest == 3){
pythia.readString("ExtraDimensionsLED:ffbar2GZ = on");
pythia.readString("ExtraDimensionsLED:n = 6");
pythia.readString("ExtraDimensionsLED:MD = 2000.");
pythia.readString("ExtraDimensionsLED:CutOffmode = 1");
pythia.readString("5000039:m0 = 3000.");
pythia.readString("5000039:mWidth = 1500.");
pythia.readString("5000039:mMin = 1.");
pythia.readString("5000039:mMax = 13990.");
pythia.readString("PhaseSpace:pTHatMin = 50.");
} else if (nTest == 4){
pythia.readString("ExtraDimensionsUnpart:ffbar2UZ = on");
pythia.readString("ExtraDimensionsUnpart:spinU = 1");
pythia.readString("ExtraDimensionsUnpart:dU = 2.0");
pythia.readString("ExtraDimensionsUnpart:LambdaU = 1000");
pythia.readString("ExtraDimensionsUnpart:lambda = 1.000");
pythia.readString("ExtraDimensionsUnpart:CutOffmode = 0");
pythia.readString("5000039:m0 = 500.");
pythia.readString("5000039:mWidth = 1000.");
pythia.readString("5000039:mMin = 1.");
pythia.readString("5000039:mMax = 13990.");
pythia.readString("PhaseSpace:pTHatMin = 50.");
} else if (nTest == 5){
pythia.readString("ExtraDimensionsLED:ffbar2gammagamma = on");
pythia.readString("ExtraDimensionsLED:gg2gammagamma = on");
pythia.readString("ExtraDimensionsLED:LambdaT = 3300.");
pythia.readString("PhaseSpace:mHatMin = 800.");
} else if (nTest == 6){
pythia.readString("ExtraDimensionsUnpart:ffbar2llbar = on");
pythia.readString("ExtraDimensionsUnpart:gg2llbar = off");
pythia.readString("ExtraDimensionsUnpart:spinU = 1");
pythia.readString("ExtraDimensionsUnpart:dU = 1.3");
pythia.readString("ExtraDimensionsUnpart:LambdaU = 1000");
pythia.readString("ExtraDimensionsUnpart:lambda = 1.0");
pythia.readString("ExtraDimensionsUnpart:gXX = 0");
pythia.readString("ExtraDimensionsUnpart:gXY = 0");
pythia.readString("PhaseSpace:mHatMin = 300.");
} else if (nTest == 7){
pythia.readString("ExtraDimensionsTEV:ffbar2mu+mu- = on");
pythia.readString("ExtraDimensionsTEV:gmZmode = 3");
pythia.readString("ExtraDimensionsTEV:nMax = 100");
pythia.readString("ExtraDimensionsTEV:mStar = 4000");
pythia.readString("PhaseSpace:mHatMin = 1000");
pythia.readString("PhaseSpace:mHatMax = 6000");
pythia.readString("5000023:isResonance = false");
} else if (nTest == 8){
pythia.readString("ExtraDimensionsG*:all = on");
} else if (nTest == 9){
pythia.readString("ExtraDimensionsG*:qqbar2KKgluon* = on");
pythia.readString("ExtraDimensionsG*:KKintMode = 2");
pythia.readString("ExtraDimensionsG*:KKgqR = -0.2");
pythia.readString("ExtraDimensionsG*:KKgqL = -0.2");
pythia.readString("ExtraDimensionsG*:KKgbR = -0.2");
pythia.readString("ExtraDimensionsG*:KKgbL = 1.0");
pythia.readString("ExtraDimensionsG*:KKgtR = 5.0");
pythia.readString("ExtraDimensionsG*:KKgtL = 1.0");
pythia.readString("5100021:m0 = 2000");
}
// Switch off sophisticated tau treatment: not yet matched to SUSY.
pythia.readString("TauDecays:mode = 0");
// Initialization for LHC.
pythia.readString("Beams:eCM = 14000.");
pythia.init();
// Validation histograms
Hist hEtjet("dN/dETjet: monojet check", 100, 0., 7000.);
Hist hMass("dN/m: graviton mass spectrum", 100, 0., 7000.);
// Begin event loop.
int iAbort = 0;
for (int iEvent = 0; iEvent < nEvent; ++iEvent) {
// Generate events. Quit if many failures.
if (!pythia.next()) {
if (++iAbort < nAbort) continue;
std::cout << " Event generation aborted prematurely, owing to error!\n";
break;
}
// Checked particle index
int tmp_monojet = -1;
// Particle loop
for (int iPart = 0; iPart < pythia.event.size(); ++iPart) {
// From hard process (inital = 21, interm.=22, final=23 state)
if (pythia.event[iPart].statusAbs() == 22) {
// Find Z_KK/gamma_KK or kk-gluon
if( pythia.event[iPart].idAbs() == 5000023
|| pythia.event[iPart].idAbs() == 5100021
|| pythia.event[iPart].idAbs() == 5100039){
hMass.fill( pythia.event[iPart].m() );
}
} else if ( pythia.event[iPart].statusAbs() == 23 ) {
// Find graviton/unparticle
if( pythia.event[iPart].idAbs() == 5000039){
hMass.fill( pythia.event[iPart].m() );
}
// Find mono-jets
if (nTest == 1 || nTest == 2) {
if ( pythia.event[iPart].idAbs() <= 6
|| pythia.event[iPart].idAbs() == 21 ){
if (tmp_monojet >= 0) {
std::cout << "More than one (hard process) mono-jet ! \n";
} else {
tmp_monojet = iPart;
}
}
}
}
}
// Validation mono-jet wrt G.Giudice et al. paper [hep-ph/9811291v2]
if (tmp_monojet >= 0) {
double tmp_eta = pythia.event[tmp_monojet].eta();
double tmp_et = pythia.event[tmp_monojet].eT();
double tmp_et_cut = 1000;
if ( tmp_et >= tmp_et_cut && abs(tmp_eta) < 3 ) {
hEtjet.fill( abs(tmp_et) );
}
}
}
// Final statistics.
pythia.stat();
cout << hMass << hEtjet;
return 0;
}