algorithms/reco/InclusiveKinematicsJB.cc

0001 // SPDX-License-Identifier: LGPL-3.0-or-later
0002 // Copyright (C) 2022 Wouter Deconinck
0003
0004 #include <edm4eic/EDM4eicVersion.h>
0005 #if EDM4EIC_VERSION_MAJOR >= 6
0006
0007 #include <Math/GenVector/LorentzVector.h>
0008 #include <Math/GenVector/PxPyPzE4D.h>
0009 #include <Math/Vector4Dfwd.h>
0010 #include <edm4eic/HadronicFinalStateCollection.h>
0011 #include <edm4eic/InclusiveKinematicsCollection.h>
0012 #include <fmt/core.h>
0013 #include <cmath>
0014 #include <gsl/pointers>
0015
0016 #include "Beam.h"
0017 #include "InclusiveKinematicsJB.h"
0018
0019 using ROOT::Math::PxPyPzEVector;
0020
0021 namespace eicrecon {
0022
0023 void InclusiveKinematicsJB::init() {}
0024
0025 void InclusiveKinematicsJB::process(const InclusiveKinematicsJB::Input& input,
0026                                     const InclusiveKinematicsJB::Output& output) const {
0027
0028   const auto [mcparts, escat, hfs] = input;
0029   auto [kinematics]                = output;
0030
0031   // Get incoming electron beam
0032   const auto ei_coll = find_first_beam_electron(mcparts);
0033   if (ei_coll.empty()) {
0034     debug("No beam electron found");
0035     return;
0036   }
0037   const PxPyPzEVector ei(round_beam_four_momentum(ei_coll[0].getMomentum(),
0038                                                   m_particleSvc.particle(ei_coll[0].getPDG()).mass,
0039                                                   {-5.0, -10.0, -18.0}, 0.0));
0040
0041   // Get incoming hadron beam
0042   const auto pi_coll = find_first_beam_hadron(mcparts);
0043   if (pi_coll.empty()) {
0044     debug("No beam hadron found");
0045     return;
0046   }
0047   const PxPyPzEVector pi(round_beam_four_momentum(pi_coll[0].getMomentum(),
0048                                                   m_particleSvc.particle(pi_coll[0].getPDG()).mass,
0049                                                   {41.0, 100.0, 275.0}, m_crossingAngle));
0050
0051   // Get hadronic final state variables
0052   if (hfs->empty()) {
0053     debug("No hadronic final state found");
0054     return;
0055   }
0056   auto sigma_h = hfs->at(0).getSigma();
0057   auto ptsum   = hfs->at(0).getPT();
0058
0059   // Sigma zero or negative
0060   if (sigma_h <= 0) {
0061     debug("Sigma zero or negative");
0062     return;
0063   }
0064
0065   // Calculate kinematic variables
0066   static const auto m_proton = m_particleSvc.particle(2212).mass;
0067   const auto y_jb            = sigma_h / (2. * ei.energy());
0068   const auto Q2_jb           = ptsum * ptsum / (1. - y_jb);
0069   const auto x_jb            = Q2_jb / (4. * ei.energy() * pi.energy() * y_jb);
0070   const auto nu_jb           = Q2_jb / (2. * m_proton * x_jb);
0071   const auto W_jb            = sqrt(m_proton * m_proton + 2 * m_proton * nu_jb - Q2_jb);
0072   auto kin                   = kinematics->create(x_jb, Q2_jb, W_jb, y_jb, nu_jb);
0073   if (escat->empty()) {
0074     debug("No scattered electron found");
0075   } else {
0076     kin.setScat(escat->at(0));
0077   }
0078
0079   debug("x,Q2,W,y,nu = {},{},{},{},{}", kin.getX(), kin.getQ2(), kin.getW(), kin.getY(),
0080         kin.getNu());
0081 }
0082
0083 } // namespace eicrecon
0084 #endif