Hadron production in $p+p$, $p+\text{Pb}$, and $\text{Pb}+\text{Pb}$ collisions with the hijing 2.0 model at energies available at the CERN Large Hadron Collider

The Heavy-Ion Jet Interaction Generator (hijing) Monte Carlo model is updated with the latest parton distributions functions and a new set of the parameters in the two-component minijet model that controls the total $p+p$ cross section and the central pseudorapity density. We study hadron spectra and multiplicity distributions using the hijing$2.0$ model and compare to recent experimental data from $p+p$ collisions at the Large Hadron Collider (LHC) energies. We also give predictions of hadron production in $p+p$, $p+\text{Pb}$, and $\text{Pb}+\text{Pb}$ collisions at the full LHC energy.

Figure 1

Total, soft, and jet production cross sections of $\mathit{pp}$ and $p\mathrm{p̄}$ collisions. The histograms in the the upper panel are calculated using hijing 1.0, while the lower histograms are calculated using hijing 2.0. The data are from Refs. [31, 32, 33, 34, 35, 36].

Figure 2

Pseudorapidity distributions of charged particles in NSD $\mathit{pp}$ at $\sqrt{s}=53$ GeV, $p\mathrm{p̄}$ collisions at $\sqrt{s}=200$, 540, 900, and 1800 GeV as compared to experimental data [37, 38].

Figure 3

Invariant inclusive cross sections of charged particles in $\mathit{pp}$ at $\sqrt{s}=53$ GeV, $p\mathrm{p̄}$ collisions at $\sqrt{s}=200$, 500, 900, and 1800 GeV. The data come from Refs. [39, 40, 41]. Both the calculation and experimental data are obtained in the region of $\left|\eta \right|<2.5$ for $\sqrt{s}=200$, 540, and 900 GeV, and $\left|\eta \right|<1.0$ for $\sqrt{s}=53$ and 1800 GeV.

Figure 4

Central pseudorapidity density at $\eta =0$ for charged particles produced in $p+p/\mathrm{p̄}$ collisions as a function of $\sqrt{s}$. The experimental data are from Refs. [37, 42, 43, 44, 45].

Figure 5

Pseudorapidity distribution ${\mathit{dN}}_{\text{ch}}/d\eta$ in inelastic $p+p$ collisions at LHC energies. The experiment data are from UA5 [37], ALICE [45], and CMS [46, 47]. Shown as the short-dashed lines are the hijing results for ALICE-defined $\text{INEL}>0$ events in which at least one charged track is required within $\left|\eta \right|<1$.

Figure 6

Pseudorapidity distribution ${\mathit{dN}}_{\text{ch}}/d\eta$ in NSD $p+p$ collisions at LHC energies. The experiment data are from UA5 [37], ALICE [45], and CMS [46, 47]. The definitions of NSD events in our calculations and the experimental data from ALICE and UA5 follow that in the UA5 experiment, as described in the text. CMS [46, 47] uses a different definition.

Figure 7

Multiplicity distributions for changed hadrons within $\left|\eta \right|<1$ in inelastic $p+p$ collisions at LHC energies from the ALICE [45] experiment compared to hijing results.

Figure 8

Multiplicity distributions for charged hadrons within different pseudorapidity intervals in NSD events of $p+p$ collisions at $\sqrt{s}=2.36$ TeV from the ALICE [45] experiment as compared to hijing results.

Figure 9

Transverse momentum distributions of charged hadron in $p+p$ collisions. The experimental data are from ALICE [49] (open squares) for inelastic $p+p$ collisions and CMS [46] (open and closed circles) for NSD $p+p$ collisions at $\sqrt{s}=0.9$ and 2.36 TeV. The histograms are results from hijing 2.0.

Figure 10

Pseudorapidity density per participant pair as a function of the average number of participants in heavy-ion collisions at different energies from hijing 2.0 calculations. Dashed lines are hijing 1.0 results. The experimental data are from Ref. [59]. Note that a vertical ofset is applied to each curve for clear illustration.

Figure 11

Pseudorapidity distributions of charged hadrons in $d+\text{Au}$ collisions at the RHIC energy $\sqrt{s}=200$ GeV/$n$ (lower panel) and $d+\text{Pb}$ collisions (upper panel) at the LHC energies. The solid lines are hijing 2.0 results with the bands corresponding to the variation of the gluon nuclear shadowing parameter $s_g=0.19$–0.24. Data at the RHIC energy are from the STAR experiment [60].