Rivet analyses
title: ALICE_2021_I1848990
Measurement of beauty and charm production at 5 TeV
Experiment: ALICE (LHC)
Inspire ID: 1848990
Status: VALIDATED
Authors: - Yonne Lourens - Maria Monalisa De Melo Paulino
References: - JHEP 05 (2021) 220 - DOI:10.1007/JHEP05(2021)220 - arXiv: 2102.13601 - Expt page: ALICE-6677
Beams: p+ p+
Beam energies: (2510.0, 2510.0)GeV
Run details: - Minimum bias events
The $p_\text{T}$-differential production cross sections of prompt and non-prompt (produced in beauty-hadron decays) D mesons were measured by the ALICE experiment at midrapidity ($|y|<0.5$) in proton-proton collisions at $\sqrt{s}$=5.02 TeV. The data sample used in the analysis corresponds to an integrated luminosity of $(19.3\pm0.4)$ nb${}^{-1}$. D mesons were reconstructed from their decays $D^0 \to K^-\pi^+$, $D^+\to K^-\pi^+\pi^+$, and $D^+\text{s} \to \varphi\pi^+\to K^-K^+\pi^+$ and their charge conjugates. Compared to previous measurements in the same rapidity region, the cross sections of prompt $D^+$ and $D^+\text{s}$ mesons have an extended $p_\text{T}$ coverage and total uncertainties reduced by a factor ranging from 1.05 to 1.6, depending on $p_\text{T}$, allowing for a more precise determination of their $p_\text{T}$-integrated cross sections. The results are well described by perturbative QCD calculations. The fragmentation fraction of heavy quarks to strange mesons divided by the one to non-strange mesons, $f_\text{s}/(f_\text{u}+f_\text{d})$, is compatible for charm and beauty quarks and with previous measurements at different centre-of-mass energies and collision systems. The $b\bar{b}$ production cross section per rapidity unit at midrapidity, estimated from non-prompt $D$-meson measurements, is $\text{d}\sigma_{b\bar{b}} / \text{d} y_{|y|<0.5}$ = 34.5 $\pm$ 2.4 (stat) ${}^{+4.7}_{-2.9}$ (tot. syst.) $\mu$b${}^{-1}$. It is compatible with previous measurements at the same centre-of-mass energy and with the cross section predicted by perturbative QCD calculations.
Source code:ALICE_2021_I1848990.cc
```c++ // -- C++ --
include "Rivet/Analysis.hh"
include "Rivet/Projections/UnstableParticles.hh"
namespace Rivet {
/// @brief Measurement of beauty and charm production iat 5 TeV class ALICE_2021_I1848990 : public Analysis { public:
RIVET_DEFAULT_ANALYSIS_CTOR(ALICE_2021_I1848990);
void init() {
const UnstableParticles fs(Cuts::absrap < 0.5);
declare(fs, "fs");
book(_h["npmD0"], 1, 1, 1); // non-prompt D0 production cross section
book(_h["npmDplus"], 2, 1, 1); // non-prompt D+ production cross section
book(_h["npmDS"], 3, 1, 1); // non-prompt DS+ production cross section
book(_h["pmD0"], 4, 1, 1); // prompt D0 production cross section
book(_h["pmDplus"], 5, 1, 1); // prompt D+ production cross section
book(_h["pmDS"], 6, 1, 1); // prompt DS+ production cross section
book(_e["npmD0_pmD0"], 7, 1, 1); // ratio between non-prompt D0 and prompt D0
book(_e["npmDplus_pmDplus"], 8, 1, 1); // ratio between non-prompt D+ and prompt D+
book(_e["npmDS_pmDS"], 9, 1, 1); // ratio between non-prompt DS+ and prompt DS+
book(_e["pmDplus_pmD0"], 10, 1, 1); // ratio between prompt D+ and prompt D0
book(_e["npmDplus_npmD0"], 11, 1, 1); // ratio between non-prompt D+ and non-prompt D0
book(_e["pmDS_pmDplusD0sum"], 12, 1, 1); // ratio between prompt DS+ and sum of prompt D0 and prompt D+
book(_e["npmDS_npmDplusD0sum"], 13, 1,
1); // ratio between non-prompt DS+ and sum of non-prompt D0 and non-prompt D+
book(_h["pmDplusD0sum"], "TMP/_pmDplusD0sum", refData(12, 1, 1));
book(_h["npmDplusD0sum"], "TMP/_npmDplusD0sum", refData(13, 1, 1));
book(_e_frag["pmDS_pmDpD0"], 14, 1, 1); // c-quark fragmentation-fraction ratio
book(_h_frag["pmDS"], "TMP/_fpmDS", refData<YODA::BinnedEstimate<string>>(14, 1, 1));
book(_h_frag["pmDpD0"], "TMP/_fpmDpD0", refData<YODA::BinnedEstimate<string>>(14, 1, 1));
book(_e_frag["npmDS_npmDpD0"], 15, 1, 1); // b-quark fragmentation-fraction ratio
book(_h_frag["npmDS"], "TMP/_npmDS", refData<YODA::BinnedEstimate<string>>(15, 1, 1));
book(_h_frag["npmDpD0"], "TMP/_npmDpD0", refData<YODA::BinnedEstimate<string>>(15, 1, 1));
}
void analyze(const Event& event) {
const UnstableParticles& fs = apply<UnstableParticles>(event, "fs");
for (const Particle& p : fs.particles()) {
if (p.fromBottom()) {
if (p.abspid() == PID::D0) {
_h["npmD0"]->fill(p.pT() / GeV);
_h["npmDplusD0sum"]->fill(p.pT() / GeV);
if (p.pT() >= 2 * GeV) _h_frag["npmDpD0"]->fill("PP --> D (Q=NON-PROMPT) + X"s);
}
else if (p.abspid() == PID::DPLUS) {
_h["npmDplus"]->fill(p.pT() / GeV);
_h["npmDplusD0sum"]->fill(p.pT() / GeV);
if (p.pT() >= 2 * GeV) _h_frag["npmDpD0"]->fill("PP --> D (Q=NON-PROMPT) + X"s);
}
else if (p.abspid() == PID::DSPLUS) {
_h["npmDS"]->fill(p.pT() / GeV);
if (p.pT() >= 2 * GeV) _h_frag["npmDS"]->fill("PP --> D (Q=NON-PROMPT) + X"s);
}
}
else {
if (p.abspid() == PID::D0) {
_h["pmD0"]->fill(p.pT() / GeV);
_h["pmDplusD0sum"]->fill(p.pT() / GeV);
if (p.pT() >= 1 * GeV) _h_frag["pmDpD0"]->fill("PP --> D (Q=PROMPT) + X"s);
}
else if (p.abspid() == PID::DPLUS) {
_h["pmDplus"]->fill(p.pT() / GeV);
_h["pmDplusD0sum"]->fill(p.pT() / GeV);
if (p.pT() >= 1 * GeV) _h_frag["pmDpD0"]->fill("PP --> D (Q=PROMPT) + X"s);
}
else if (p.abspid() == PID::DSPLUS) {
_h["pmDS"]->fill(p.pT() / GeV);
if (p.pT() >= 1 * GeV) _h_frag["pmDS"]->fill("PP --> D (Q=PROMPT) + X"s);
}
}
}
}
void finalize() {
const double sf = crossSection() / (microbarn * 2 * sumOfWeights());
scale(_h, sf);
scale(_h_frag, 0.5 * sf);
for (auto& item : _e) {
size_t delim = item.first.find("_");
YODA::Histo1D num = *_h[item.first.substr(0, delim)];
if (!item.second->binning().isCompatible(num.binning())) {
num = num.clone();
num.rebinXTo(item.second->xEdges());
}
YODA::Histo1D den = *_h[item.first.substr(delim + 1)];
if (!item.second->binning().isCompatible(den.binning())) {
den = den.clone();
den.rebinXTo(item.second->xEdges());
}
divide(num, den, item.second);
}
for (auto& item : _e_frag) {
size_t delim = item.first.find("_");
divide(_h_frag[item.first.substr(0, delim)], _h_frag[item.first.substr(delim + 1)], item.second);
}
}
private:
map<string, Histo1DPtr> _h;
map<string, BinnedHistoPtr<string>> _h_frag;
map<string, Estimate1DPtr> _e;
map<string, BinnedEstimatePtr<string>> _e_frag;
};
RIVET_DECLARE_PLUGIN(ALICE_2021_I1848990);
} ```