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Probing small Bjorken-$x$ nuclear gluonic structure via coherent J/$\psi$ photoproduction in ultraperipheral PbPb collisions at $\sqrt{s_\mathrm{NN}}$ = 5.02 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
Phys.Rev.Lett. 131 (2023) 262301, 2023.
Inspire Record 2648536 DOI 10.17182/hepdata.138867

Quasireal photons exchanged in relativistic heavy ion interactions are powerful probes of the gluonic structure of nuclei. The coherent J/$\psi$ photoproduction cross section in ultraperipheral lead-lead collisions is measured as a function of photon-nucleus center-of-mass energies per nucleon (W$^\text{Pb}_{\gamma\text{N}}$), over a wide range of 40 $\lt$ W$^\text{Pb}_{\gamma\text{N}}$$\lt$ 400 GeV. Results are obtained using data at the nucleon-nucleon center-of-mass energy of 5.02 TeV collected by the CMS experiment at the CERN LHC, corresponding to an integrated luminosity of 1.52 nb$^{-1}$. The cross section is observed to rise rapidly at low W$^\text{Pb}_{\gamma\text{N}}$, and plateau above W$^\text{Pb}_{\gamma\text{N}}$$\approx$ 40 GeV, up to 400 GeV, a new regime of small Bjorken-$x$ ($\approx$ 6 $\times$ 10$^{-5}$) gluons being probed in a heavy nucleus. The observed energy dependence is not predicted by current quantum chromodynamic models.

16 data tables

The differential coherent $\mathrm{J}/\psi$ photoproduction cross section as a function of rapidity, in different neutron multiplicity classes: 0n0n, 0nXn, XnXn , and AnAn.

The differential coherent $\mathrm{J}/\psi$ photoproduction cross section as a function of rapidity, in different neutron multiplicity classes: 0n0n, 0nXn, XnXn , and AnAn.

The total coherent $\mathrm{J}/\psi$ photoproduction cross section as a function of photon-nuclear center-of-mass energy per nucleon $W_{\gamma \mathrm{N}}^{\mathrm{Pb}}$, measured in PbPb ultra-peripheral collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV. The $W_{\gamma \mathrm{N}}^{\mathrm{Pb}}$ values used correspond to the center of each rapidity range. The theoretical uncertainties is due to the uncertainties in the photon flux.

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Study of Drell-Yan dimuon production in proton-lead collisions at $\sqrt{s_\mathrm{NN}} =$ 8.16 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 05 (2021) 182, 2021.
Inspire Record 1849180 DOI 10.17182/hepdata.88292

Differential cross sections for the Drell-Yan process, including Z boson production, using the dimuon decay channel are measured in proton-lead (pPb) collisions at a nucleon-nucleon centre-of-mass energy of 8.16 TeV. A data sample recorded with the CMS detector at the LHC is used, corresponding to an integrated luminosity of 173 nb$^{-1}$. The differential cross section as a function of the dimuon mass is measured in the range 15-600 GeV, for the first time in proton-nucleus collisions. It is also reported as a function of dimuon rapidity over the mass ranges 15-60 GeV and 60-120 GeV, and ratios for the p-going over the Pb-going beam directions are built. In both mass ranges, the differential cross sections as functions of the dimuon transverse momentum $p_\mathrm{T}$ and of a geometric variable $\phi^*$ are measured, where $\phi^*$ highly correlates with $p_\mathrm{T}$ but is determined with higher precision. In the Z mass region, the rapidity dependence of the data indicate a modification of the distribution of partons within a lead nucleus as compared to the proton case. The data are more precise than predictions based upon current models of parton distributions.

28 data tables

Differential fiducial cross section (without the acceptance correction) for the DY process measured in the muon channel, as a function of dimuon invariant mass. The quoted error is the quadratic sum of the statistical and systematic uncertainties. The global normalisation uncertainty of 3.5% is listed separately.

Differential fiducial cross section (without the acceptance correction) for the DY process measured in the muon channel, as a function of rapidity in the centre-of-mass frame for $15<m_{\mu\mu}<60$ GeV. The quoted error is the quadratic sum of the statistical and systematic uncertainties. The global normalisation uncertainty of 3.5% is listed separately.

Differential fiducial cross section (without the acceptance correction) for the DY process measured in the muon channel, as a function of rapidity in the centre-of-mass frame for $60<m_{\mu\mu}<120$ GeV. The quoted error is the quadratic sum of the statistical and systematic uncertainties. The global normalisation uncertainty of 3.5% is listed separately.

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Evidence for top quark production in nucleus-nucleus collisions

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev.Lett. 125 (2020) 222001, 2020.
Inspire Record 1802092 DOI 10.17182/hepdata.93878

Ultrarelativistic heavy ion collisions recreate in the laboratory the thermodynamical conditions prevailing in the early universe up to 10$^{-6}$ seconds, thereby allowing the study of the quark-gluon plasma (QGP), a state of quantum chromodynamics (QCD) matter with deconfined partons. The top quark, the heaviest elementary particle known, is accessible in nucleus-nucleus collisions at the CERN LHC, and constitutes a novel probe of the QGP. Here, we report the first-ever evidence for the production of top quarks in nucleus-nucleus collisions, using lead-lead collision data at a nucleon-nucleon centre-of-mass energy of 5.02 TeV recorded by the CMS experiment. Two methods are used to measure the cross section for top quark pair production ($\sigma_\mathrm{t\bar{t}}$) via the decay into charged leptons (electrons or muons) and bottom quarks. One method relies on the leptonic information alone, and the second one exploits, in addition, the presence of bottom quarks. The measured cross sections, $\sigma_\mathrm{t\bar{t}} = $ 2.54 $^{+0.84}_{-0.74}$ and 2.03 $^{+0.71}_{-0.64}$ $\mu$b, respectively, are compatible with expectations from scaled proton-proton data and QCD predictions.

1 data table

Inclusive $\mathrm{t\bar{t}}$ cross sections measured with two methods, relying on the leptonic information alone ($2\ell_{\mathrm{OS}}$), and the second one exploits, in addition, the presence of bottom quarks ($2\ell_{\mathrm{OS}}+N_{\mathrm{b-tag}}$), in the combined $\mathrm{e}^+\mathrm{e}^-$, $\mu^+\mu^-$, and $\mathrm{e}^\pm\mu^\mp$ final states in PbPb collisions at 5.02 TeV, and pp results at $\sqrt{\smash[b]{s}}=5.02$ TeV (scaled by $A^2$) from JHEP 03 (2018) 115. The measurements are compared with theoretical predictions at NNLO+NNLL accuracy in QCD. The inner (outer) experimental uncertainty bars include statistical (statistical and systematic, added in quadrature) uncertainties. The inner (outer) theoretical uncertainty bands correspond to nuclear or free-nucleon PDF (PDF and scale, added in quadrature) uncertainties.


Measurement of the central exclusive production of charged particle pairs in proton-proton collisions at $\sqrt{s} = 200$ GeV with the STAR detector at RHIC

The STAR collaboration Adam, Jaroslav ; Adamczyk, Leszek ; Adams, Joseph ; et al.
JHEP 07 (2020) 178, 2020.
Inspire Record 1792394 DOI 10.17182/hepdata.94264

We report on the measurement of the Central Exclusive Production of charged particle pairs $h^{+}h^{-}$ ($h = \pi, K, p$) with the STAR detector at RHIC in proton-proton collisions at $\sqrt{s} = 200$ GeV. The charged particle pairs produced in the reaction $pp\to p^\prime+h^{+}h^{-}+p^\prime$ are reconstructed from the tracks in the central detector, while the forward-scattered protons are measured in the Roman Pot system. Differential cross sections are measured in the fiducial region, which roughly corresponds to the square of the four-momentum transfers at the proton vertices in the range $0.04~\mbox{GeV}^2 < -t_1 , -t_2 < 0.2~\mbox{GeV}^2$, invariant masses of the charged particle pairs up to a few GeV and pseudorapidities of the centrally-produced hadrons in the range $|\eta|<0.7$. The measured cross sections are compared to phenomenological predictions based on the Double Pomeron Exchange (DPE) model. Structures observed in the mass spectra of $\pi^{+}\pi^{-}$ and $K^{+}K^{-}$ pairs are consistent with the DPE model, while angular distributions of pions suggest a dominant spin-0 contribution to $\pi^{+}\pi^{-}$ production. The fiducial $\pi^+\pi^-$ cross section is extrapolated to the Lorentz-invariant region, which allows decomposition of the invariant mass spectrum into continuum and resonant contributions. The extrapolated cross section is well described by the continuum production and at least three resonances, the $f_0(980)$, $f_2(1270)$ and $f_0(1500)$, with a possible small contribution from the $f_0(1370)$. Fits to the extrapolated differential cross section as a function of $t_1$ and $t_2$ enable extraction of the exponential slope parameters in several bins of the invariant mass of $\pi^+\pi^-$ pairs. These parameters are sensitive to the size of the interaction region.

47 data tables

Differential fiducial cross section for CEP of $\pi^+\pi^-$ pairs as a function of the invariant mass of the pair. Systematic uncertainties assigned to data points are strongly correlated between bins and should be treated as allowed collective variation of all data points. There are two components of the total systematic uncertainty. The systematic uncertainty related to the experimental tools and analysis method is labeled "syst. (experimental)". The systematic uncertainty related to the integrated luminosity (fully correlated between all data points) is labeled "syst. (luminosity)". Fiducial region definition: * central state $\pi^+$, $\pi^-$ - $p_{\mathrm{T}} > 0.2~\mathrm{GeV}$ - $|\eta| < 0.7$ * intact forward-scattered beam protons $p'$ - $p_x > -0.2~\mathrm{GeV}$ - $0.2~\mathrm{GeV} < |p_{y}| < 0.4~\mathrm{GeV}$ - $(p_x+0.3~\mathrm{GeV})^2 + p_y^2 < 0.25~\mathrm{GeV}^2$

Differential fiducial cross section for CEP of $K^+K^-$ pairs as a function of the invariant mass of the pair. Systematic uncertainties assigned to data points are strongly correlated between bins and should be treated as allowed collective variation of all data points. There are two components of the total systematic uncertainty. The systematic uncertainty related to the experimental tools and analysis method is labeled "syst. (experimental)". The systematic uncertainty related to the integrated luminosity (fully correlated between all data points) is labeled "syst. (luminosity)". Fiducial region definition: * central state $K^+$, $K^-$ - $p_{\mathrm{T}} > 0.3~\mathrm{GeV}$ - $min(p_{\mathrm{T}}(K^+), p_{\mathrm{T}}(K^-)) < 0.7~\mathrm{GeV}$ - $|\eta| < 0.7$ * intact forward-scattered beam protons $p'$ - $p_x > -0.2~\mathrm{GeV}$ - $0.2~\mathrm{GeV} < |p_{y}| < 0.4~\mathrm{GeV}$ - $(p_x+0.3~\mathrm{GeV})^2 + p_y^2 < 0.25~\mathrm{GeV}^2$

Differential fiducial cross section for CEP of $p\bar{p}$ pairs as a function of the invariant mass of the pair. Systematic uncertainties assigned to data points are strongly correlated between bins and should be treated as allowed collective variation of all data points. There are two components of the total systematic uncertainty. The systematic uncertainty related to the experimental tools and analysis method is labeled "syst. (experimental)". The systematic uncertainty related to the integrated luminosity (fully correlated between all data points) is labeled "syst. (luminosity)". Fiducial region definition: * central state $p$, $\bar{p}$ - $p_{\mathrm{T}} > 0.4~\mathrm{GeV}$ - $min(p_{\mathrm{T}}(p), p_{\mathrm{T}}(\bar{p})) < 1.1~\mathrm{GeV}$ - $|\eta| < 0.7$ * intact forward-scattered beam protons $p'$ - $p_x > -0.2~\mathrm{GeV}$ - $0.2~\mathrm{GeV} < |p_{y}| < 0.4~\mathrm{GeV}$ - $(p_x+0.3~\mathrm{GeV})^2 + p_y^2 < 0.25~\mathrm{GeV}^2$

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Results on Total and Elastic Cross Sections in Proton-Proton Collisions at $\sqrt{s} = 200$ GeV

The STAR collaboration Adam, Jaroslav ; Adamczyk, Leszek ; Adams, Joseph ; et al.
Phys.Lett.B 808 (2020) 135663, 2020.
Inspire Record 1791591 DOI 10.17182/hepdata.94263

We report results on the total and elastic cross sections in proton-proton collisions at $\sqrt{s}=200$ GeV obtained with the Roman Pot setup of the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The elastic differential cross section was measured in the squared four-momentum transfer range $0.045 \leq -t \leq 0.135$ GeV$^2$. The value of the exponential slope parameter $B$ of the elastic differential cross section $d\sigma/dt \sim e^{-Bt}$ in the measured $-t$ range was found to be $B = 14.32 \pm 0.09 (stat.)^{\scriptstyle +0.13}_{\scriptstyle -0.28} (syst.)$ GeV$^{-2}$. The total cross section $\sigma_{tot}$, obtained from extrapolation of the $d\sigma/dt$ to the optical point at $-t = 0$, is $\sigma_{tot} = 54.67 \pm 0.21 (stat.) ^{\scriptstyle +1.28}_{\scriptstyle -1.38} (syst.)$ mb. We also present the values of the elastic cross section $\sigma_{el} = 10.85 \pm 0.03 (stat.) ^{\scriptstyle +0.49}_{\scriptstyle -0.41}(syst.)$ mb, the elastic cross section integrated within the STAR $t$-range $\sigma^{det}_{el} = 4.05 \pm 0.01 (stat.) ^{\scriptstyle+0.18}_{\scriptstyle -0.17}(syst.)$ mb, and the inelastic cross section $\sigma_{inel} = 43.82 \pm 0.21 (stat.) ^{\scriptstyle +1.37}_{\scriptstyle -1.44} (syst.)$ mb. The results are compared with the world data.

3 data tables

The proton-proton elastic differential cross-section $d\sigma_{el}/dt$ in the t-range 0.045<|t|<0.135 $GeV^{2}$ at sqrt(s) = 200 GeV.

The B-slope of the exponential fit A*exp(-B*|t|) to the single differential proton-proton elastic cross-section in the t-range 0.045<|t|<0.135 GeV**2 at sqrt(s) = 200 GeV.

The total, elastic and inelastic cross-sections for proton-proton scattering at sqrt(s)=200 GeV, the elastic cross-section measured in the t-range 0.045<|t|<0.135 GeV^2 and the value of the differential cross-section extrapolated to |t| = 0.


Underlying Event properties in pp collisions at $\sqrt{s}$ = 13 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
JHEP 04 (2020) 192, 2020.
Inspire Record 1762350 DOI 10.17182/hepdata.94414

This article reports measurements characterizing the Underlying Event (UE) associated with hard scatterings at midrapidity in pp collisions at $\sqrt{s}=13$ TeV. The hard scatterings are identified by the leading particle, the charged particle with the highest transverse momentum ($p_{\rm T}^{\rm leading}$) in the event. Charged-particle number and summed transverse-momentum densities are measured in different azimuthal regions defined with respect to the leading particle direction: Toward, Transverse, and Away. The Toward and Away regions contain the fragmentation products of the hard scatterings in addition to the UE contribution, whereas particles in the Transverse region are expected to originate predominantly from the UE. The study is performed as a function of $p_{\rm T}^{\rm leading}$ with three different $p_{\rm T}$ thresholds for the associated particles, $p_{\rm T}^{\rm min} >$ 0.15, 0.5, and 1.0 GeV/$c$. The charged-particle density in the Transverse region rises steeply for low values of $p_{\rm T}^{\rm leading}$ and reaches a plateau. The results confirm the trend that the charged-particle density in the Transverse region shows a stronger increase with $\sqrt{s}$ than the inclusive charged-particle density at midrapidity. The UE activity is increased by approximately 20% when going from 7 to 13 TeV. The plateau in the Transverse region ($5 < p_{\rm T}^{\rm leading} < ~ 40$ GeV/$c$ ) is further characterized by the probability distribution of its charged-particle multiplicity normalized to its average value (relative transverse activity, $R_{T}$) and the mean transverse momentum as a function of $R_{T}$. Experimental results are compared to model calculations using PYTHIA 8 and EPOS LHC. The overall agreement between models and data is within 30%. These measurements provide new insights on the interplay between hard scatterings and the associated UE in pp collisions.

5 data tables

Fig. 3: Number density $N_{ch}$ (left) and $\\Sigma p_{T}$ (right) distributions as a function of $p_{T}^{leading}$ in Toward, Transverse, and Away regions for $p_{T}^{track} >$ 0.15 GeV/$c$. The shaded areas represent the systematic uncertainties and vertical error bars indicate statistical uncertainties.

Fig. 9: R_T probability distribution in the Transverse region for $p_{T}^{track} >$ 0.15 GeV/$c$ and $|\\eta|<$ 0.8. The result (solid circles) is compared to the PYTHIA 8 and EPOS LHC calculations (lines). The red line represents the result of the NBD fit, where the multiplicity is scaled by its mean value, m. The parameter k is related to the standard deviation of the distribution via $\\sigma$ = $\\sqrt{ \\frac{1}{m} + \\frac{1}{k} }$. The open boxes represent the systematic uncertainties and vertical error bars indicate statistical uncertainties. No uncertainties are shown for the MC calculations. The bottom panel shows the ratio between the NBD fit, as well as those of the MC to the data.

Fig. 10: $<p_{T}>$ in the Transverse region as a function of $R_{T}$ for $p_{T}^{track} >$ 0.15 GeV/$c$ and $|\\eta|<$ 0.8. Data (solid circles) are compared to the results of PYTHIA 8 and EPOS LHC calculations (lines). The open boxes represent the systematic uncertainties and vertical error bars indicate statistical uncertainties. No uncertainties are shown for the MC calculations. The bottom panel shows the ratio of the MC to data.

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Multiplicity dependence of K*(892)$^{0}$ and $\phi$(1020) production in pp collisions at $\sqrt{s}$ = 13 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
Phys.Lett.B 807 (2020) 135501, 2020.
Inspire Record 1762348 DOI 10.17182/hepdata.96957

Measurements of identified hadrons as a function of the charged-particle multiplicity in pp collisions enable a search for the onset of collective effects in small collision systems. With such measurements, it is possible to study the mechanisms that determine the shapes of hadron transverse momentum ($p_{\rm{T}}$) spectra, to search for possible modifications of the yields of short-lived hadronic resonances due to scattering effects in the hadron-gas phase, and to investigate different explanations for the multiplicity evolution of strangeness production provided by phenomenological models. In this paper, these topics are addressed through measurements of the $\rm{K}^{*}(892)^{0}$ and $\phi(1020)$ mesons at midrapidity in pp collisions at $\sqrt{s}$ = 13 TeV as a function of the charged-particle multiplicity. The results include the $p_{\rm{T}}$ spectra, $p_{\rm{T}}$-integrated yields, mean transverse momenta, and the ratios of the yields of these resonances to those of longer-lived hadrons. Comparisons with results from other collision systems and energies, as well as predictions from phenomenological models, are also discussed.

60 data tables

K$^{*0}$ transverse momentum spectrum - V0M multiplicity class I, average of particle and antiparticle

K$^{*0}$ transverse momentum spectrum - V0M multiplicity class II, average of particle and antiparticle

K$^{*0}$ transverse momentum spectrum - V0M multiplicity class III, average of particle and antiparticle

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Version 2
Multiplicity dependence of (multi-)strange hadron production in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adhya, Souvik Priyam ; et al.
Eur.Phys.J.C 80 (2020) 167, 2020.
Inspire Record 1748157 DOI 10.17182/hepdata.93535

The production rates and the transverse momentum distribution of strange hadrons at mid-rapidity ($\ |y\ | < 0.5$) are measured in proton-proton collisions at $\sqrt{s}$ = 13 TeV as a function of the charged particle multiplicity, using the ALICE detector at the LHC. The production rates of $\rm{K}^{0}_{S}$, $\Lambda$, $\Xi$, and $\Omega$ increase with the multiplicity faster than what is reported for inclusive charged particles. The increase is found to be more pronounced for hadrons with a larger strangeness content. Possible auto-correlations between the charged particles and the strange hadrons are evaluated by measuring the event-activity with charged particle multiplicity estimators covering different pseudorapidity regions. When comparing to lower energy results, the yields of strange hadrons are found to depend only on the mid-rapidity charged particle multiplicity. Several features of the data are reproduced qualitatively by general purpose QCD Monte Carlo models that take into account the effect of densely-packed QCD strings in high multiplicity collisions. However, none of the tested models reproduce the data quantitatively. This work corroborates and extends the ALICE findings on strangeness production in proton-proton collisions at 7 TeV.

121 data tables

$K^{0}_{S}$ transverse momentum spectrum - V0M multiplicity classes. Total systematic uncertainties include both correlated and uncorrelated uncertainties across multiplicity. Uncorrelated systematic originating from the multiplicity dependence of the efficiency (2%) is not included.

$K^{0}_{S}$ transverse momentum spectrum - V0M multiplicity classes. Total systematic uncertainties include both correlated and uncorrelated uncertainties across multiplicity. Uncorrelated systematic originating from the multiplicity dependence of the efficiency (2%) is not included.

$\Lambda+\bar{\Lambda}$ transverse momentum spectrum - V0M multiplicity classes. Total systematic uncertainties include both correlated and uncorrelated uncertainties across multiplicity. Uncorrelated systematic originating from the multiplicity dependence of the efficiency (2%) is not included.

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Measurement of prompt D$^0$, D$^+$, D$^{*+}$, and D$^+_s$ production in p$-$Pb collisions at $\mathbf{\sqrt{{\textit s}_{\rm NN}}~=~5.02~TeV}$

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adhya, Souvik Priyam ; et al.
JHEP 12 (2019) 092, 2019.
Inspire Record 1738950 DOI 10.17182/hepdata.93013

The measurement of the production of prompt D$^0$, D$^+$, D$^{*+}$, and D$^+_s$ mesons in proton$-$lead (p$-$Pb) collisions at the centre-of-mass energy per nucleon pair of $\sqrt{s_{\rm NN}}$ = 5.02 TeV, with an integrated luminosity of $292\pm 11$ $\mu$b$^{-1}$, are reported. Differential production cross sections are measured at mid-rapidity ($-0.96<y_{\rm cms}<0.04$) as a function of transverse momentum ($p_{\rm T}$) in the intervals $0< p_{\rm T} < 36$ GeV/$c$ for D$^0$, $1< p_{\rm T} <36$ GeV/$c$ for D$^+$ and D$^{*+}$, and $2< p_{\rm T} <24$ GeV/$c$ for D$^+_s$ mesons. For each species, the nuclear modification factor $R_{\rm pPb}$ is calculated as a function of $p_{\rm T}$ using a proton-proton (pp) reference measured at the same collision energy. The results are compatible with unity in the whole $p_{\rm T}$ range. The average of the non-strange D mesons $R_{\rm pPb}$ is compared with theoretical model predictions that include initial-state effects and parton transport model predictions. The $p_{\rm T}$ dependence of the D$^0$, D$^+$, and D$^{*+}$ nuclear modification factors is also reported in the interval $1< p_{\rm T} < 36$ GeV/$c$ as a function of the collision centrality, and the central-to-peripheral ratios are computed from the D-meson yields measured in different centrality classes. The results are further compared with charged-particle measurements and a similar trend is observed in all the centrality classes. The ratios of the $p_{\rm T}$-differential cross sections of D$^0$, D$^+$, D$^{*+}$, and D$^+_s$ mesons are also reported. The D$^+_s$ and D$^+$ yields are compared as a function of the charged-particle multiplicity for several $p_{\rm T}$ intervals. No modification in the relative abundances of the four species is observed with respect to pp collisions within the statistical and systematic uncertainties.

27 data tables

$p_{\rm{T}}$ differential cross section of prompt D0 mesons obtained from the analysis without vertexing reconstruction in p-Pb collisions at $\mathbf{\sqrt{{\textit s}_{\rm NN}}~=~5.02~TeV}$.

$p_{\rm{T}}$ differential cross section of inclusive D0 mesons from the analysis without vertexing reconstruction in p-Pb collisions at $\mathbf{\sqrt{{\textit s}_{\rm NN}}~=~5.02~TeV}$.

$p_{\rm{T}}$ differential cross section of inclusive D0 mesons from the analysis without vertexing reconstruction in pp collisions at $\mathbf{\sqrt{{\textit s}}~=~5.02~TeV}$ multiplied by A=208.

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Measurement of charged jet cross section in $pp$ collisions at ${\sqrt{s}=5.02}$ TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adhya, Souvik Priyam ; et al.
Phys.Rev.D 100 (2019) 092004, 2019.
Inspire Record 1733689 DOI 10.17182/hepdata.91239

The cross section of jets reconstructed from charged particles is measured in the transverse momentum range of $5<p_\mathrm{T}<100\ \mathrm{GeV}/c$ in pp collisions at the center-of-mass energy of $\sqrt{s} = 5.02\ \mathrm{TeV}$ with the ALICE detector. The jets are reconstructed using the anti-$k_\mathrm{T}$ algorithm with resolution parameters $R=0.2$, $0.3$, $0.4$, and $0.6$ in the pseudorapidity range $|\eta|< 0.9-R$. The charged jet cross sections are compared with the leading order (LO) and to next-to-leading order (NLO) perturbative Quantum ChromoDynamics (pQCD) calculations. It was found that the NLO calculations agree better with the measurements. The cross section ratios for different resolution parameters were also measured. These ratios increase from low $p_\mathrm{T}$ to high $p_\mathrm{T}$ and saturate at high $p_\mathrm{T}$, indicating that jet collimation is larger at high $p_\mathrm{T}$ than at low $p_\mathrm{T}$. These results provide a precision test of pQCD predictions and serve as a baseline for the measurement in Pb$-$Pb collisions at the same energy to quantify the effects of the hot and dense medium created in heavy-ion collisions at the LHC.

4 data tables

Fig. 3: Fully corrected charged jet differential cross sections in pp collisions at $\\sqrt{s}$ = 5.02 TeV. Statistical uncertainties are displayed as vertical error bars. The total systematic uncertainties are shown as shaded bands around the data points. Data are scaled to enhance visibility.

Fig. 6: Charged jet cross section ratios for $\\sigma$(R = 0.2)/$\\sigma$(R = 0.4) (Red) and $\\sigma$(R = 0.2)/$\\sigma$(R = 0.6). The systematic uncertainty of the cross section ratio is indicated by a shaded band drawn around data points.

Charged jet differential cross sections with UE subtraction in pp collisions at $\sqrt{s}$ = 5.02 TeV. Statistical uncertainties are displayed as vertical error bars. The total systematic uncertainties are shown as shaded bands around the data points. Data are scaled to enhance visibility.

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