Rivet analyses

title: TOTEM_2014_I1328627

Forward charged particle pseudorapidity density in $pp$ collisions at $\sqrt{s} = 8 \TeV$ using a displaced interaction point

Experiment: TOTEM (LHC)

Inspire ID: 1328627

Status: VALIDATED

Authors: - Sercan Sen

References: - EPJ C75,126 - CERN-PH-EP-2014-260 - arXiv: 1411.4963

Beams: p+ p+

Beam energies: (4000.0, 4000.0)GeV

Run details: - $pp$ QCD interactions at 8 TeV.

The pseudorapidity density of charged particles $\mathrm{d}N_\mathrm{ch}/\mathrm{d}\eta$ is measured by the TOTEM experiment in $pp$ collisions at $\sqrt{s} = 8$ TeV within the ranges $3.9 < \eta < 4.7$ and $-6.95 < \eta < -6.9$. Data were collected in a low intensity LHC run with collisions occurring at a distance of 11.25\,m from the nominal interaction point. The data sample is expected to include 96--97\% of the inelastic proton--proton interactions. The measurement reported here considers charged particles with $p_T > 0$ MeV/$c$, produced in inelastic interactions with at least one charged particle in $-7 < \eta < -6$ or $3.7 < \eta < 4.8$. The $\mathrm{d}N_\mathrm{ch}/\mathrm{d}\eta$ has been found to decrease with $|\eta|$, from $5.11 \pm 0.73$ at $\eta = 3.95$ to $1.81 \pm 0.56$ at $\eta = -6.925$.

Source code:TOTEM_2014_I1328627.cc

```c++ // -- C++ --

include "Rivet/Analysis.hh"

include "Rivet/Projections/ChargedFinalState.hh"

namespace Rivet {

class TOTEM_2014_I1328627 : public Analysis { public:

RIVET_DEFAULT_ANALYSIS_CTOR(TOTEM_2014_I1328627);


void init() {
  ChargedFinalState cfsm(Cuts::etaIn(-7.0, -6.0));
  ChargedFinalState cfsp(Cuts::etaIn(3.7, 4.8));
  declare(cfsm, "CFSM");
  declare(cfsp, "CFSP");

  book(_h_eta, 1, 1, 1);
  book(_sumofweights, "sumofweights");
}


void analyze(const Event& event) {
  const ChargedFinalState cfsm = apply<ChargedFinalState>(event, "CFSM");
  const ChargedFinalState cfsp = apply<ChargedFinalState>(event, "CFSP");
  if (cfsm.size() == 0 && cfsp.size() == 0) vetoEvent;

  _sumofweights->fill();
  for (const Particle& p : cfsm.particles() + cfsp.particles()) {
    _h_eta->fill(p.abseta());
  }
}


void finalize() {
  scale(_h_eta, 1. / *_sumofweights);
}

private:

CounterPtr _sumofweights;
Histo1DPtr _h_eta;

};

RIVET_DECLARE_PLUGIN(TOTEM_2014_I1328627);

} ```