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Measurement of the nuclear modification factor for inclusive jets in Pb+Pb collisions at $\sqrt{s_\mathrm{NN}}=5.02$ TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2018.
Inspire Record 1673184 DOI 10.17182/hepdata.84819

Measurements of the yield and nuclear modification factor, $R_\mathrm{ AA}$, for inclusive jet production are performed using 0.49 nb$^{-1}$ of Pb+Pb data at $\sqrt{s_\mathrm{NN}} = 5.02$ TeV and 25 pb$^{-1}$ of $pp$ data at $\sqrt{s}=5.02$ TeV with the ATLAS detector at the LHC. Jets are reconstructed with the anti-$k_t$ algorithm with radius parameter $R=0.4$ and are measured over the transverse momentum range of 40-1000 GeV in six rapidity intervals covering $|y|<2.8$. The magnitude of $R_\mathrm{ AA}$ increases with increasing jet transverse momentum, reaching a value of approximately 0.6 at 1 TeV in the most central collisions. The magnitude of $R_\mathrm{ AA}$ also increases towards peripheral collisions. The value of $R_\mathrm{ AA}$ is independent of rapidity at low jet transverse momenta, but it is observed to decrease with increasing rapidity at high transverse momenta.

35 data tables

The ⟨TAA⟩ and ⟨Npart⟩ values and their uncertainties in each centrality bin.

No description provided.

No description provided.

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Production of $\Lambda $ -hyperons in inelastic p+p interactions at 158 ${\mathrm{GeV}}\!/\!c$

The NA61/SHINE collaboration Aduszkiewicz, A. ; Ali, Y. ; Andronov, E. ; et al.
Eur.Phys.J. C76 (2016) 198, 2016.
Inspire Record 1397634 DOI 10.17182/hepdata.76910

Inclusive production of $\Lambda $ -hyperons was measured with the large acceptance NA61/SHINE spectrometer at the CERN SPS in inelastic p+p interactions at beam momentum of 158  ${\mathrm{GeV}}\!/\!c$ . Spectra of transverse momentum and transverse mass as well as distributions of rapidity and x$_{_F}$ are presented. The mean multiplicity was estimated to be $0.120\,{\pm }\,0.006\,(stat.)\,{\pm }0.010\,(sys.)$ . The results are compared with previous measurements and predictions of the Epos, Urqmd and Fritiof models.

6 data tables

Double-differential yield $\frac{d^2n}{dydp_{_T}}$.

Double-differential yield $\frac{d^2n}{dydm_{_T}}$.

Double-differential yields, $\frac{d^{2}n}{x_{_F}p_{_T}}$ and $f_n(x_{_F},p_{T})$, for $x_{_F}<0$.

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Measurement of D-meson production versus multiplicity in p-Pb collisions at $ \sqrt{{\mathrm{s}}_{\mathrm{NN}}}=5.02 $ TeV

The ALICE collaboration Adam, J. ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
JHEP 1608 (2016) 078, 2016.
Inspire Record 1423072 DOI 10.17182/hepdata.73775

The measurement of prompt D-meson production as a function of multiplicity in p-Pb collisions at $ \sqrt{s_{\mathrm{NN}}}=5.02 $ TeV with the ALICE detector at the LHC is reported. D$^{0}$, D$^{+}$ and D$^{∗+}$ mesons are reconstructed via their hadronic decay channels in the centre-of-mass rapidity range −0.96 < y$_{cms}$ < 0.04 and transverse momentum interval 1<p$_{T}$ <24 GeV/c. The multiplicity dependence of D-meson production is examined by either comparing yields in p-Pb collisions in different event classes, selected based on the multiplicity of produced particles or zero-degree energy, with those in pp collisions, scaled by the number of binary nucleon-nucleon collisions (nuclear modification factor), as well as by evaluating the per-event yields in p-Pb collisions in different multiplicity intervals normalised to the multiplicity-integrated ones (relative yields). The nuclear modification factors for D$^{0}$, D$^{+}$ and D$^{∗+}$ are consistent with one another. The D-meson nuclear modification factors as a function of the zero-degree energy are consistent with unity within uncertainties in the measured p$_{T}$ regions and event classes. The relative D-meson yields, calculated in various p$_{T}$ intervals, increase as a function of the charged-particle multiplicity. The results are compared with the equivalent pp measurements at $ \sqrt{s}=7 $ TeV as well as with EPOS 3 calculations.

5 data tables

Average $Q_{\rm pPb}$ of D$^{0}$, D$^{+}$ and D*$^{+}$ mesons for the sum of particles and antiparticles in several multiplicity and PT(D) intervals for p-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV as a function of the multiplicity at central rapidity evaluated with the ZNA estimator. The values are reported together with their uncertainties, which are quoted as statistical followed by systematic uncertainties. Normalisation uncertainty is not quoted and amounts to $\pm 0.07$, $\pm 0.05$, $\pm 0.07$ and $\pm 0.08$ for the 0-20%, 20-40%, 40-60% and 60-100% intervals, respectively.

Average $Q_{\rm pPb}$ of D$^{0}$, D$^{+}$ and D*$^{+}$ mesons for the sum of particles and antiparticles in several multiplicity and PT(D) intervals for p-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV as a function of the multiplicity at central rapidity evaluated with the CL1 estimator. The values are reported together with their uncertainties, which are quoted as statistical followed by systematic uncertainties. Normalisation uncertainty is not quoted and amounts to $\pm 0.05$, $\pm 0.05$, $\pm 0.07$ and $\pm 0.23$ for the 0-20%, 20-40%, 40-60% and 60-100% intervals, respectively.

Average $Q_{\rm pPb}$ of D$^{0}$, D$^{+}$ and D*$^{+}$ mesons for the sum of particles and antiparticles in several multiplicity and PT(D) intervals for p-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV as a function of the multiplicity at central rapidity evaluated with the V0A estimator. The values are reported together with their uncertainties, which are quoted as statistical followed by systematic uncertainties. Normalisation uncertainty is not quoted and amounts to $\pm 0.05$, $\pm 0.05$, $\pm 0.06$ and $\pm 0.22$ for the 0-20%, 20-40%, 40-60% and 60-100% intervals, respectively.

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Multiplicity dependence of charged pion, kaon, and (anti)proton production at large transverse momentum in p-Pb collisions at $\mathbf{\sqrt{{\textit s}_{\rm NN}}}$ = 5.02 TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
Phys.Lett. B760 (2016) 720-735, 2016.
Inspire Record 1415274 DOI 10.17182/hepdata.73749

The production of charged pions, kaons and (anti)protons has been measured at mid-rapidity ($-0.5 < y < 0$) in p-Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV using the ALICE detector at the LHC. Exploiting particle identification capabilities at high transverse momentum ($p_{\rm T}$), the previously published $p_{\rm T}$ spectra have been extended to include measurements up to 20 GeV/$c$ for seven event multiplicity classes. The $p_{\rm T}$ spectra for pp collisions at $\sqrt{s}=7$ TeV, needed to interpolate a pp reference spectrum, have also been extended up to 20 GeV/$c$ to measure the nuclear modification factor ($R_{\rm pPb}$) in non-single diffractive p-Pb collisions. At intermediate transverse momentum ($2 < p_{\rm T} < 10$\,GeV/$c$) the proton-to-pion ratio increases with multiplicity in p-Pb collisions, a similar effect is not present in the kaon-to-pion ratio. The $p_{\rm T}$ dependent structure of such increase is qualitatively similar to those observed in pp and heavy-ion collisions. At high $p_{\rm T}$ ($>10$ GeV/$c$), the particle ratios are consistent with those reported for pp and Pb-Pb collisions at the LHC energies. At intermediate $p_{\rm T}$ the (anti)proton $R_{\rm pPb}$ shows a Cronin-like enhancement, while pions and kaons show little or no nuclear modification. At high $p_{\rm T}$ the charged pion, kaon and (anti)proton $R_{\rm pPb}$ are consistent with unity within statistical and systematic uncertainties.

13 data tables

pT-differential invariant yield of charged pions in p-Pb collisions with centre-of-mass energy/nucleon=5.02 TeV, measured for different V0A multiplicity classes. The first uncertainty is statistical, the second one is the total systematic uncertainty, while the third one is the uncorrelated systematic uncertainty which is multiplicity dependent.

pT-differential invariant yield of charged pions in p-Pb collisions with centre-of-mass energy/nucleon=5.02 TeV, measured for NSD events. The first uncertainty is statistical, the second one is the total systematic uncertainty, while the third one is the uncorrelated systematic uncertainty which is multiplicity dependent.

pT-differential invariant yield of charged kaons in p-Pb collisions with centre-of-mass energy/nucleon=5.02 TeV, measured for different V0A multiplicity classes. The first uncertainty is statistical, the second one is the total systematic uncertainty, while the third one is the uncorrelated systematic uncertainty which is multiplicity dependent.

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Near-side azimuthal and pseudorapidity correlations using neutral strange baryons and mesons in d+Au, Cu+Cu and Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV

The STAR collaboration Abelev, B. ; Adamczyk, L. ; Adkins, J.K. ; et al.
Phys.Rev. C94 (2016) 014910, 2016.
Inspire Record 1429700 DOI 10.17182/hepdata.73657
11 data tables

Corrected 2D $K_S^0$ correlation function for 3 < $p_T^{trigger}$ < 6 GeV/$c$ and 1.5 GeV/$c$ < $p_T^{associated}$ < $p_T^{trigger}$ for 0-20% Cu+Cu. The data have been reflected about $\Delta\eta$ = 0 and $\Delta\phi$ = 0.

Corrected correlation functions $\frac{dN_{J}}{d\Delta\eta}$ in $\mid$$\Delta\eta$$\mid<$ 0.78 for 3 < $p_T^{trigger}$ < 6 GeV/$c$ and 1.5 GeV/$c$ < $p_T^{associated}$ < $p_T^{trigger}$ for (a) $\Lambda$-h and (b) $K_S^0$-h for minimum bias $d$+Au, 0-20% Cu+Cu, and 40-80% Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV after background subtraction. The data have been reflected about $\Delta\eta$ = 0.

$\Lambda$/$K^0_S$ ratio measured in the jet-like correlation in 0-60% Cu+Cu collisions at $\sqrt{s_{NN}}$ = 200 GeV for 3 < $p_T^{trigger}$ < 6 GeV/$c$ and \assocrange{2.0}{3.0} along with this ratio obtained from inclusive $p_T$ spectra in \pp collisions.

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Measurements of Dielectron Production in Au$+$Au Collisions at $\sqrt{s_{\rm NN}}$ = 200 GeV from the STAR Experiment

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Rev. C92 (2015) 024912, 2015.
Inspire Record 1357992 DOI 10.17182/hepdata.73504

We report on measurements of dielectron (e+e−) production in Au+Au collisions at a center-of-mass energy of 200 GeV per nucleon-nucleon pair using the STAR detector at BNL Relativistic Heavy Ion Collider. Systematic measurements of the dielectron yield as a function of transverse momentum (pT) and collision centrality show an enhancement compared to a cocktail simulation of hadronic sources in the low invariant-mass region (Mee<1GeV/c2). This enhancement cannot be reproduced by the ρ-meson vacuum spectral function. In minimum-bias collisions, in the invariant-mass range of 0.30–0.76GeV/c2, integrated over the full pT acceptance, the enhancement factor is 1.76±0.06(stat.)±0.26(sys.)±0.29(cocktail). The enhancement factor exhibits weak centrality and pT dependence in STAR's accessible kinematic regions, while the excess yield in this invariant-mass region as a function of the number of participating nucleons follows a power-law shape with a power of 1.44±0.10. Models that assume an in-medium broadening of the ρ-meson spectral function consistently describe the observed excess in these measurements. Additionally, we report on measurements of ω- and ϕ-meson production through their e+e− decay channel. These measurements show good agreement with Tsallis blast-wave model predictions, as well as, in the case of the ϕ meson, results through its K+K− decay channel. In the intermediate invariant-mass region (1.1<Mee<3GeV/c2), we investigate the spectral shapes from different collision centralities. Physics implications for possible in-medium modification of charmed hadron production and other physics sources are discussed.

50 data tables

Estimated electron purity vs. momentum in 200 GeV Au + Au collisions.

Acceptance correction factor for unlike-sign and like-sign pair difference from 200 GeV Au+Au minimum-bias collisions.

Ratio of the same-event like-sign to the mixed event unlike-sign distributions.

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Observation of $D^0$ Meson Nuclear Modifications in Au+Au Collisions at $\sqrt{s_{NN}}=200$  GeV

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Rev.Lett. 113 (2014) 142301, 2014.
Inspire Record 1292132 DOI 10.17182/hepdata.73474

We report the first measurement of charmed-hadron ($D^0$) production via the hadronic decay channel ($D^0\rightarrow K^- + \pi^+$) in Au+Au collisions at $\sqrt{s_{_{\mathrm{NN}}}}$ = 200\,GeV with the STAR experiment. The charm production cross-section per nucleon-nucleon collision at mid-rapidity scales with the number of binary collisions, $N_{bin}$, from $p$+$p$ to central Au+Au collisions. The $D^0$ meson yields in central Au+Au collisions are strongly suppressed compared to those in $p$+$p$ scaled by $N_{bin}$, for transverse momenta $p_{T}>3$ GeV/$c$, demonstrating significant energy loss of charm quarks in the hot and dense medium. An enhancement at intermediate $p_{T}$ is also observed. Model calculations including strong charm-medium interactions and coalescence hadronization describe our measurements.

3 data tables

Centrality dependence of the $D^0$ $p_T$ differential invariant yield in Au+Au collisions.

$D^0\,R_{AA}$ for different centralities.

Integrated $D^0$ $R_{AA}$ as a function of $N_{part}$ in different $p_T$ regions.


Di-hadron correlations with identified leading hadrons in 200 GeV Au + Au and d + Au collisions at STAR

The STAR collaboration Adamczyk, L. ; Adamczyk, L. ; Adkins, J.K. ; et al.
Phys.Lett. B751 (2015) 233-240, 2015.
Inspire Record 1322126 DOI 10.17182/hepdata.73458

The STAR Collaboration presents for the first time two-dimensional di-hadron correlations with identified leading hadrons in 200 GeV central Au + Au and minimum-bias d + Au collisions to explore hadronization mechanisms in the quark gluon plasma. The enhancement of the jet-like yield for leading pions in Au + Au data with respect to the d + Au reference and the absence of such an enhancement for leading non-pions (protons and kaons) are discussed within the context of a quark recombination scenario. The correlated yield at large angles, specifically in the ridge region , is found to be significantly higher for leading non-pions than pions. The consistencies of the constituent quark scaling, azimuthal harmonic model and a mini-jet modification model description of the data are tested, providing further constraints on hadronization.

14 data tables

Two-dimensional $\Delta\phi$ vs. $\Delta\eta$ correlation functions for charged hadron triggers from minimum-bias d+Au data at 200 GeV. All trigger and associated charged hadrons are selected in the respective pT ranges 4 < $p_T^{trig}$ < 5 GeV/c and 1.5 < $p_T^{assoc}$ < 4 GeV/c.

Two-dimensional $\Delta\phi$ vs. $\Delta\eta$ correlation functions for charged hadron triggers from 0-10% most-central Au+Au data at 200 GeV. All trigger and associated charged hadrons are selected in the respective pT ranges 4 < $p_T^{trig}$ < 5 GeV/c and 1.5 < $p_T^{assoc}$ < 4 GeV/c.

Two-dimensional $\Delta\phi$ vs. $\Delta\eta$ correlation functions for non-pion triggers from minimum-bias d+Au data at 200 GeV. All trigger and associated charged hadrons are selected in the respective pT ranges 4 < $p_T^{trig}$ < 5 GeV/c and 1.5 < $p_T^{assoc}$ < 4 GeV/c.

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Effect of event selection on jetlike correlation measurement in $d$+Au collisions at $\sqrt{s_{\rm{NN}}}=200$ GeV

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Lett. B743 (2015) 333-339, 2015.
Inspire Record 1335765 DOI 10.17182/hepdata.73235

Dihadron correlations are analyzed in sNN=200 GeV d+Au collisions classified by forward charged particle multiplicity and zero-degree neutral energy in the Au-beam direction. It is found that the jetlike correlated yield increases with the event multiplicity. After taking into account this dependence, the non-jet contribution on the away side is minimal, leaving little room for a back-to-back ridge in these collisions.

16 data tables

The dihadron correlated yield normalized per radian per unit of pseudorapidity as function of $\Delta\eta$ in d+Au collisions on the near (|$\Delta\phi$| < $\pi$/3). Shown is the low FTPC-Au activity data. Trigger and associated particles have 1 < $p_T$ < 3 GeV/c and |$\eta$| < 1.

The dihadron correlated yield normalized per radian per unit of pseudorapidity as function of $\Delta\eta$ in d+Au collisions on the away side (|$\Delta\phi$ - $\pi$| < $\pi$/3. Shown is the high FTPC-Au activity data. Trigger and associated particles have 1 < $p_T$ < 3 GeV/c and |$\eta$| < 1.

The dihadron correlated yield normalized per radian per unit of pseudorapidity as function of $\Delta\eta$ in d+Au collisions on the near (|$\Delta\phi$| < $\pi$/3) side. Shown is the high-activity data after subtracting the unscaled. Trigger and associated particles have 1 < $p_T$ < 3 GeV/c and |$\eta$| < 1.

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Direct photon production in Pb-Pb collisions at $\sqrt{s_\rm{NN}} =$ 2.76 TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
Phys.Lett. B754 (2016) 235-248, 2016.
Inspire Record 1394677 DOI 10.17182/hepdata.73093

Direct photon production at mid-rapidity in Pb–Pb collisions at sNN=2.76 TeV was studied in the transverse momentum range 0.9<pT<14 GeV/c . Photons were detected with the highly segmented electromagnetic calorimeter PHOS and via conversions in the ALICE detector material with the e+e− pair reconstructed in the central tracking system. The results of the two methods were combined and direct photon spectra were measured for the 0–20%, 20–40%, and 40–80% centrality classes. For all three classes, agreement was found with perturbative QCD calculations for pT≳5 GeV/c . Direct photon spectra down to pT≈1 GeV/c could be extracted for the 20–40% and 0–20% centrality classes. The significance of the direct photon signal for 0.9<pT<2.1 GeV/c is 2.6 σ for the 0–20% class. The spectrum in this pT range and centrality class can be described by an exponential with an inverse slope parameter of (297±12stat±41syst) MeV . State-of-the-art models for photon production in heavy-ion collisions agree with the data within uncertainties.

9 data tables

Invariant differential yields of direct GAMMA produced in 0-20% central inelastic PbPb collisions at center-of-mass energy per nucleon 2.76 TeV.

Invariant differential yields of direct GAMMA produced in 20-40% central inelastic PbPb collisions at center-of-mass energy per nucleon 2.76 TeV. The quoted upper limits correspond to a 95% confidence level.

Invariant differential yields of direct GAMMA produced in 40-80% central inelastic PbPb collisions at center-of-mass energy per nucleon 2.76 TeV. The quoted upper limits correspond to a 95% confidence level.

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Differential studies of inclusive J/ψ and ψ(2S) production at forward rapidity in Pb-Pb collisions at $ \sqrt{s_{\mathrm{NN}}}=2.76 $ TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
JHEP 1605 (2016) 179, 2016.
Inspire Record 1380192 DOI 10.17182/hepdata.73094

The production of J/ψ and ψ(2S) was studied with the ALICE detector in Pb-Pb collisions at the LHC. The measurement was performed at forward rapidity (2.5 < y < 4) down to zero transverse momentum (p$_{t}$ ) in the dimuon decay channel. Inclusive J/ψ yields were extracted in different centrality classes and the centrality dependence of the average p$_{t}$ is presented. The J/ψ suppression, quantified with the nuclear modification factor (R$_{AA}$), was measured as a function of centrality, transverse momentum and rapidity. Comparisons with similar measurements at lower collision energy and theoretical models indicate that the J/ψ production is the result of an interplay between color screening and recombination mechanisms in a deconfined partonic medium, or at its hadronization. Results on the ψ(2S) suppression are provided via the ratio of ψ(2S) over J/ψ measured in pp and Pb-Pb collisions.

16 data tables

Values of $\langle p_{\rm T}\rangle$ and $\langle p^2_{\rm T}\rangle$ of inclusive J/$\psi$ measured in $0<p_{\rm T}<8$ GeV/$c$ and $2.5<y<4$. Statistical and systematic uncertainties are also reported.

Inclusive J/$\psi$ yields in $p_{\rm T}$ intervals for the 0-20%, 20-40% and 40-90% most central Pb-Pb collisions. The rapidity range is $2.5<y<4$. Statistical and systematic uncertainties are also reported. A global systematic uncertainty of 4% affects all the values. A 2%, 1% and 2% systematic uncertainty, independent of $p_{\rm T}$, affects the centrality classes 0-20%, 20-40% and 40-90%, respectively.

Inclusive J/$\psi$ $R_{\rm AA}$ and Pb-Pb yields as a function of centrality, $p_{\rm T}<8$ GeV/$c$ and $2.5<y<4.0$. Statistical and systematic uncertainties are also reported. A global systematic uncertainty of 15% (12%) affects all the $R_{\rm AA}$ (yields) values.

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Multi-strange baryon production in p-Pb collisions at $\sqrt{s_\mathbf{NN}}=5.02$ TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
Phys.Lett. B758 (2016) 389-401, 2016.
Inspire Record 1411084 DOI 10.17182/hepdata.73011

The multi-strange baryon yields in Pb--Pb collisions have been shown to exhibit an enhancement relative to pp reactions. In this work, $\Xi$ and $\Omega$ production rates have been measured with the ALICE experiment as a function of transverse momentum, ${p_{\rm T}}$, in p-Pb collisions at a centre-of-mass energy of ${\sqrt{s_{\rm NN}}}$ = 5.02 TeV. The results cover the kinematic ranges 0.6 GeV/$c<{p_{\rm T}} <$7.2 GeV/$c$ and 0.8 GeV/$c<{p_{\rm T}}<$ 5 GeV/$c$, for $\Xi$ and $\Omega$ respectively, in the common rapidity interval -0.5 $<{y_{\rm CMS}}<$ 0. Multi-strange baryons have been identified by reconstructing their weak decays into charged particles. The ${p_{\rm T}}$ spectra are analysed as a function of event charged-particle multiplicity, which in p-Pb collisions ranges over one order of magnitude and lies between those observed in pp and Pb-Pb collisions. The measured ${p_{\rm T}}$ distributions are compared to the expectations from a Blast-Wave model. The parameters which describe the production of lighter hadron species also describe the hyperon spectra in high multiplicity p-Pb. The yield of hyperons relative to charged pions is studied and compared with results from pp and Pb-Pb collisions. A statistical model is employed, which describes the change in the ratios with volume using a canonical suppression mechanism, in which the small volume causes a species-dependent relative reduction of hadron production. The calculations, in which the magnitude of the effect depends on the strangeness content, show good qualitative agreement with the data.

24 data tables

Xi pt spectrum in 0-5% multiplicity class.

Xi pt spectrum in 5-10% multiplicity class.

Xi pt spectrum in 10-20% multiplicity class.

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$K^0_S$ and $\Lambda$ production in Pb-Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV

The ALICE collaboration Abelev, Betty Bezverkhny ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Rev.Lett. 111 (2013) 222301, 2013.
Inspire Record 1243863 DOI 10.17182/hepdata.61857

The ALICE measurement of KS0 and Λ production at midrapidity in Pb-Pb collisions at sNN=2.76  TeV is presented. The transverse momentum (pT) spectra are shown for several collision centrality intervals and in the pT range from 0.4  GeV/c (0.6  GeV/c for Λ) to 12  GeV/c. The pT dependence of the Λ/KS0 ratios exhibits maxima in the vicinity of 3  GeV/c, and the positions of the maxima shift towards higher pT with increasing collision centrality. The magnitude of these maxima increases by almost a factor of three between most peripheral and most central Pb-Pb collisions. This baryon excess at intermediate pT is not observed in pp interactions at s=0.9  TeV and at s=7  TeV. Qualitatively, the baryon enhancement in heavy-ion collisions is expected from radial flow. However, the measured pT spectra above 2  GeV/c progressively decouple from hydrodynamical-model calculations. For higher values of pT, models that incorporate the influence of the medium on the fragmentation and hadronization processes describe qualitatively the pT dependence of the Λ/KS0 ratio.

23 data tables

pT spectra of K0Short in the rapidity range -0.5<y<0.5 in the centrality interval 0.0-5.0%.

pT spectra of K0Short in the rapidity range -0.5<y<0.5 in the centrality interval 5.0-10.0%.

pT spectra of K0Short in the rapidity range -0.5<y<0.5 in the centrality interval 10.0-20.0%.

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Long-range pseudorapidity dihadron correlations in $d$+Au collisions at $\sqrt{s_{\rm NN}}=200$ GeV

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Lett. B747 (2015) 265-271, 2015.
Inspire Record 1346551 DOI 10.17182/hepdata.72303

Dihadron angular correlations in $d$+Au collisions at $\sqrt{s_{\rm NN}}=200$ GeV are reported as a function of the measured zero-degree calorimeter neutral energy and the forward charged hadron multiplicity in the Au-beam direction. A finite correlated yield is observed at large relative pseudorapidity ($\Delta\eta$) on the near side (i.e. relative azimuth $\Delta\phi\sim0$). This correlated yield as a function of $\Delta\eta$ appears to scale with the dominant, primarily jet-related, away-side ($\Delta\phi\sim\pi$) yield. The Fourier coefficients of the $\Delta\phi$ correlation, $V_{n}=\langle\cos n\Delta\phi\rangle$, have a strong $\Delta\eta$ dependence. In addition, it is found that $V_{1}$ is approximately inversely proportional to the mid-rapidity event multiplicity, while $V_{2}$ is independent of it with similar magnitude in the forward ($d$-going) and backward (Au-going) directions.

23 data tables

Correlated dihadron yield, per radian per unit of pseudorapidity, as a function of $\Delta\phi$ for 1.2 < $|\Delta\eta|$ < 1.8 in d+Au collisions, for low ZDC-Au activity data. Both the trigger and associated particles have 1 < $p_T$ < 3 GeV/c.

Correlated dihadron yield, per radian per unit of pseudorapidity, as a function of $\Delta\phi$ for 1.2 < $|\Delta\eta|$ < 1.8 in d+Au collisions, for high ZDC-Au activity data. Both the trigger and associated particles have 1 < $p_T$ < 3 GeV/c.

Correlated dihadron yield, per radian per unit of pseudorapidity, as a function of $\Delta\phi$ for -4.5 < $\Delta\eta$ < -2 in d+Au collisions, for low ZDC-Au activity data. Both the trigger and associated particles have 1 < $p_T$ < 3 GeV/c.

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Energy dependence of acceptance-corrected dielectron excess mass spectrum at mid-rapidity in Au$+$Au collisions at $\sqrt{s_{NN}} =$ 19.6 and 200 GeV

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Lett. B750 (2015) 64-71, 2015.
Inspire Record 1340691 DOI 10.17182/hepdata.72236

The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity |yee|<1 in minimum-bias Au+Au collisions at sNN=19.6 and 200 GeV. The excess mass spectra are consistently described by a model calculation with a broadened ρ spectral function for Mee<1.1 GeV/c2 . The integrated dielectron excess yield at sNN=19.6 GeV for 0.4<Mee<0.75 GeV/c2 , normalized to the charged particle multiplicity at mid-rapidity, has a value similar to that in In+In collisions at sNN=17.3 GeV . For sNN=200 GeV , the normalized excess yield in central collisions is higher than that at sNN=17.3 GeV and increases from peripheral to central collisions. These measurements indicate that the lifetime of the hot, dense medium created in central Au+Au collisions at sNN=200 GeV is longer than those in peripheral collisions and at lower energies.

6 data tables

Reconstructed dielectron unlike-sign pairs, like-sign pairs and signal distributions, together with the signal to background ratio (S/B). All columns are presented as a function of dielectron invariant mass in Au+Au collisions at $\sqrt{s_{NN}}$ = 19.6 GeV.

Dielectron invariant mass spectrum in the STAR acceptance (|$y_{ee}$| < 1, 0.2 < $p_T^e$ < 3 GeV/c, |$\eta^e$ | < 1) after efficiency correction in Au+Au collisions at $\sqrt{s_{NN}}$ = 19.6 GeV.

Hadronic cocktail consisting of the decays of light hadrons and correlated decays of charm in Au+Au collisions at $\sqrt{s_{NN}}$ = 19.6 GeV.

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Probing parton dynamics of QCD matter with $\Omega$ and $\phi$ production

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Rev. C93 (2016) 021903, 2016.
Inspire Record 1378002 DOI 10.17182/hepdata.72068

We present measurements of Ω and ϕ production at midrapidity from Au+Au collisions at nucleon-nucleon center-of-mass energies sNN=7.7, 11.5, 19.6, 27, and 39 GeV by the STAR experiment at the BNL Relativistic Heavy Ion Collider (RHIC). Motivated by the coalescence formation mechanism for these strange hadrons, we study the ratios of N(Ω−+Ω¯+)/[2N(ϕ)]. These ratios as a function of transverse momentum pT fall on a consistent trend at high collision energies, but start to show deviations in peripheral collisions at sNN=19.6, 27, and 39 GeV, and in central collisions at 11.5 GeV in the intermediate pT region of 2.4−3.6 GeV/c. We further evaluate empirically the strange quark pT distributions at hadronization by studying the Ω/ϕ ratios scaled by the number of constituent quarks (NCQ). The NCQ-scaled Ω/ϕ ratios show a suppression of strange quark production in central collisions at 11.5 GeV compared to sNN≥19.6 GeV. The shapes of the presumably thermal strange quark distributions in 0–60% most central collisions at 7.7 GeV show significant deviations from those in 0–10% most central collisions at higher energies. These features suggest that there is likely a change of the underlying strange quark dynamics in the transition from quark matter to hadronic matter at collision energies below 19.6 GeV.

85 data tables

Phi Meson Spectra.

Phi Meson Spectra.

Phi Meson Spectra.

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Transverse momentum distribution and nuclear modification factor of charged particles in $p$-Pb collisions at $\sqrt{s_{NN}}=5.02$ TeV

The ALICE collaboration Abelev, Betty ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Rev.Lett. 110 (2013) 082302, 2013.
Inspire Record 1190895 DOI 10.17182/hepdata.37287

The transverse momentum (pT) distribution of primary charged particles is measured in minimum bias (non-single-diffractive) p+Pb collisions at sNN=5.02  TeV with the ALICE detector at the LHC. The pT spectra measured near central rapidity in the range 0.5<pT<20  GeV/c exhibit a weak pseudorapidity dependence. The nuclear modification factor RpPb is consistent with unity for pT above 2  GeV/c. This measurement indicates that the strong suppression of hadron production at high pT observed in Pb+Pb collisions at the LHC is not due to an initial-state effect. The measurement is compared to theoretical calculations.

4 data tables

Normalized differential primary charged particle yield.

pp INEL cross section scaled by nuclear overlap.

Nuclear Modification Factor R_pPb in the central region.

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Measurement of charm and beauty production at central rapidity versus charged-particle multiplicity in proton-proton collisions at $ \sqrt{s}=7 $ TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
JHEP 1509 (2015) 148, 2015.
Inspire Record 1366028 DOI 10.17182/hepdata.69529

Prompt D meson and non-prompt J/ψ yields are studied as a function of the multiplicity of charged particles produced in inelastic proton-proton collisions at a centre-of-mass energy of $ \sqrt{s}=7 $ TeV. The results are reported as a ratio between yields in a given multiplicity interval normalised to the multiplicity-integrated ones (relative yields). They are shown as a function of the multiplicity of charged particles normalised to the average value for inelastic collisions (relative charged-particle multiplicity). D$^{0}$, D$^{+}$ and D$^{*+}$ mesons are measured in five p$_{T}$ intervals from 1 GeV/c to 20 GeV/c and for |y| < 0.5 via their hadronic decays. The D-meson relative yield is found to increase with increasing charged-particle multiplicity. For events with multiplicity six times higher than the average multiplicity of inelastic collisions, a yield enhancement of a factor about 15 relative to the multiplicity-integrated yield in inelastic collisions is observed. The yield enhancement is independent of transverse momentum within the uncertainties of the measurement. The D$^{0}$-meson relative yield is also measured as a function of the relative multiplicity at forward pseudo-rapidity. The non-prompt J/ψ, i.e. the B hadron, contribution to the inclusive J/ψ production is measured in the di-electron decay channel at central rapidity. It is evaluated for p$_{T}$ > 1.3 GeV/c and |y| < 0.9, and extrapolated to p$_{T}$ > 0. The fraction of non-prompt J/ψ in the inclusive J/ψ yields shows no dependence on the charged-particle multiplicity at central rapidity. Charm and beauty hadron relative yields exhibit a similar increase with increasing charged-particle multiplicity. The measurements are compared to PYTHIA 8, EPOS 3 and percolation calculations.

7 data tables

Average of D$^{0}$, D$^{+}$ and D*$^{+}$ mesons relative yields for the sum of particle and antiparticle in several multiplicity and PT intervals for PP collisions at $\sqrt{s}=7$ TeV as a function of the relative charged-particle multiplicity at central rapidity. The values are reported together with their uncertainties, which are quoted in the the order: statistical, systematic and feed-down contribution uncertainties. The yields reported here are per inelastic event.

Average of D$^{0}$, D$^{+}$ and D*$^{+}$ mesons relative yields for the sum of particle and antiparticle in several multiplicity and PT intervals for PP collisions at $\sqrt{s}=7$ TeV as a function of the relative charged-particle multiplicity at central rapidity. The values are reported together with their uncertainties, which are quoted in the the order: statistical, systematic and feed-down contribution uncertainties. The yields reported here are not corrected by the trigger selection efficiency, they are normalised to the visible cross section.

D$^{0}$-meson relative yields for the sum of particle and antiparticle in several multiplicity and PT intervals for pp collisions at $\sqrt{s}=7$ TeV as a function of the relative average multiplicity in the V0 detector, $N_{V0} \big/ \langle N_{V0} \rangle$. The yields reported here are normalised to the inelastic cross section.

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$^{3}_{\Lambda}\mathrm H$ and $^{3}_{\bar{\Lambda}} \overline{\mathrm H}$ production in Pb-Pb collisions at $\sqrt{s_{\rm NN}} =$ 2.76 TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
Phys.Lett. B754 (2016) 360-372, 2016.
Inspire Record 1380234 DOI 10.17182/hepdata.70861
4 data tables

(Hypertriton + Anti-Hypertriton)dN/d(ct) distribution.

Hypertriton and Anti-hypertriton $p_{\rm T}$ spectra x B.R.

$B_2$ as a function of $p_{\rm T}$/A for Hypertriton.

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Pseudorapidity and transverse-momentum distributions of charged particles in proton–proton collisions at $\sqrt s=$ 13 TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
Phys.Lett. B753 (2016) 319-329, 2016.
Inspire Record 1395253 DOI 10.17182/hepdata.70847

The pseudorapidity ( η ) and transverse-momentum ( pT ) distributions of charged particles produced in proton–proton collisions are measured at the centre-of-mass energy s=13 TeV . The pseudorapidity distribution in |η|<1.8 is reported for inelastic events and for events with at least one charged particle in |η|<1 . The pseudorapidity density of charged particles produced in the pseudorapidity region |η|<0.5 is 5.31±0.18 and 6.46±0.19 for the two event classes, respectively. The transverse-momentum distribution of charged particles is measured in the range 0.15<pT<20 GeV/c and |η|<0.8 for events with at least one charged particle in |η|<1 . The evolution of the transverse momentum spectra of charged particles is also investigated as a function of event multiplicity. The results are compared with calculations from PYTHIA and EPOS Monte Carlo generators.

4 data tables

Average pseudorapidity density of charged particles as a function of eta produced in pp collisions at sqrt(s) = 13 TeV. The results are shown in the normalisation classes INEL and INEL>0. The uncertainties are the quadratic sum of statistical and systematic contributions.

Invariant charged-particle yield as a function of pT normalised to INEL>0 events.

Ratio of transverse-momentum spectra in INEL>0 events at $\sqrt{s}$ = 13 and 7 TeV.

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Measurement of jet suppression in central Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
Phys.Lett. B746 (2015) 1-14, 2015.
Inspire Record 1343112 DOI 10.17182/hepdata.68483

The transverse momentum ( pT ) spectrum and nuclear modification factor ( RAA ) of reconstructed jets in 0–10% and 10–30% central Pb–Pb collisions at sNN=2.76 TeV were measured. Jets were reconstructed using the anti- kT jet algorithm with a resolution parameter of R=0.2 from charged and neutral particles, utilizing the ALICE tracking detectors and Electromagnetic Calorimeter (EMCal). The jet pT spectra are reported in the pseudorapidity interval of |ηjet|<0.5 for 40<pT,jet<120 GeV/c in 0–10% and for 30<pT,jet<100 GeV/c in 10–30% collisions. Reconstructed jets were required to contain a leading charged particle with pT>5 GeV/c to suppress jets constructed from the combinatorial background in Pb–Pb collisions. The leading charged particle requirement applied to jet spectra both in pp and Pb–Pb collisions had a negligible effect on the RAA . The nuclear modification factor RAA was found to be 0.28±0.04 in 0–10% and 0.35±0.04 in 10–30% collisions, independent of pT,jet within the uncertainties of the measurement. The observed suppression is in fair agreement with expectations from two model calculations with different approaches to jet quenching.

7 data tables

The $\delta{p}_{\mathrm{T}}$ distribution for $R=0.2$ with the random-cone and the embedded-track methods in the 10% most central events, with $p_{\mathrm{T}}^{\mathrm{probe}}=60$ GeV/$c$ for the embedded-track method.

The spectra of $R=0.2$ jets with a leading track requirement of $5$ GeV/$c$ in inelastic pp collisions at $\sqrt{s}=2.76$ TeV.

The spectra of $R=0.2$ jets with a leading track requirement of $5$ GeV/$c$ in 0-10% and 10-30% most central Pb-Pb collisions scaled by 1/$N_{\mathrm{coll}}$ at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV.

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Measurements of the Nuclear Modification Factor for Jets in Pb+Pb Collisions at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV with the ATLAS Detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.Lett. 114 (2015) 072302, 2015.
Inspire Record 1326911 DOI 10.17182/hepdata.66021

<p>Measurements of inclusive jet production are performed in <inline-formula><mml:math display="inline"><mml:mi>p</mml:mi><mml:mi>p</mml:mi></mml:math></inline-formula> and <inline-formula><mml:math display="inline"><mml:mi>Pb</mml:mi><mml:mo>+</mml:mo><mml:mi>Pb</mml:mi></mml:math></inline-formula> collisions at <inline-formula><mml:math display="inline"><mml:msqrt><mml:msub><mml:mi>s</mml:mi><mml:mi>NN</mml:mi></mml:msub></mml:msqrt><mml:mo>=</mml:mo><mml:mn>2.76</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>TeV</mml:mi></mml:math></inline-formula> with the ATLAS detector at the LHC, corresponding to integrated luminosities of 4.0 and <inline-formula><mml:math display="inline"><mml:mrow><mml:mn>0.14</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:msup><mml:mrow><mml:mi>nb</mml:mi></mml:mrow><mml:mrow><mml:mo>-</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math></inline-formula>, respectively. The jets are identified with the anti-<inline-formula><mml:math display="inline"><mml:msub><mml:mi>k</mml:mi><mml:mi>t</mml:mi></mml:msub></mml:math></inline-formula> algorithm with <inline-formula><mml:math display="inline"><mml:mi>R</mml:mi><mml:mo>=</mml:mo><mml:mn>0.4</mml:mn></mml:math></inline-formula>, and the spectra are measured over the kinematic range of jet transverse momentum <inline-formula><mml:math display="inline"><mml:mn>32</mml:mn><mml:mo>&lt;</mml:mo><mml:msub><mml:mi>p</mml:mi><mml:mi mathvariant="normal">T</mml:mi></mml:msub><mml:mo>&lt;</mml:mo><mml:mn>500</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>GeV</mml:mi></mml:math></inline-formula> and absolute rapidity <inline-formula><mml:math display="inline"><mml:mo stretchy="false">|</mml:mo><mml:mi>y</mml:mi><mml:mo stretchy="false">|</mml:mo><mml:mo>&lt;</mml:mo><mml:mn>2.1</mml:mn></mml:math></inline-formula> and as a function of collision centrality. The nuclear modification factor <inline-formula><mml:math display="inline"><mml:msub><mml:mi>R</mml:mi><mml:mi>AA</mml:mi></mml:msub></mml:math></inline-formula> is evaluated, and jets are found to be suppressed by approximately a factor of 2 in central collisions compared to <inline-formula><mml:math display="inline"><mml:mi>p</mml:mi><mml:mi>p</mml:mi></mml:math></inline-formula> collisions. The <inline-formula><mml:math display="inline"><mml:msub><mml:mi>R</mml:mi><mml:mi>AA</mml:mi></mml:msub></mml:math></inline-formula> shows a slight increase with <inline-formula><mml:math display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi>p</mml:mi></mml:mrow><mml:mrow><mml:mi mathvariant="italic">T</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math></inline-formula> and no significant variation with rapidity.</p>

46 data tables

The $\langle T_{\mathrm{AA}} \rangle $ and $\langle N_{\mathrm{part}} \rangle$ values and their uncertainties in each centrality bin.

No description provided.

No description provided.

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Charged particle nuclear modification factor and pseudorapidity asymmetry in pPb collisions at sqrt(sNN)=5.02 TeV with CMS

The CMS collaboration
No Journal Information, None.
Inspire Record 1263706 DOI 10.17182/hepdata.66742

The charged particle transverse momentum spectra in the midrapidity and forward pseudorapidity ranges are presented for pPb collisions at $\sqrt{s_{\rm NN}}=5.02$~TeV. The data sample corresponding to an integrated luminosity of 26~${\rm nb}^{-1}$ was collected with the CMS detector at the LHC. The nuclear modification factor is measured at midrapidity by normalizing the measured pPb spectrum to a pp reference spectrum constructed from previous measurements. In addition, the asymmetries in the charged particle yields between equivalent positive and negative pseudorapidity ranges in the center-of-mass frame are presented as a function of transverse momentum.

11 data tables

Invariant charged particle differential yield.

Invariant charged particle differential yield.

Invariant charged particle differential yield.

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Study of Z production in PbPb and pp collisions at $ \sqrt{s_{\mathrm{NN}}}=2.76 $ TeV in the dimuon and dielectron decay channels

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 1503 (2015) 022, 2015.
Inspire Record 1322726 DOI 10.17182/hepdata.66612
15 data tables

The measured Z boson production cross section in pp collisions as a function of the Z boson pT for the dimuon decay channel in |y|<2.0.

The measured Z boson production cross section in pp collisions as a function of the Z boson pT for the dielectron decay channel in |y|<1.44.

The measured Z boson production cross section in pp collisions as a function of the Z boson rapidity for the dimuon decay channel.

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Prompt and non-prompt $J/\psi$ production in $pp$ collisions at $\sqrt{s}=7$ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Eur.Phys.J. C71 (2011) 1575, 2011.
Inspire Record 878118 DOI 10.17182/hepdata.57532

The production of J/psi mesons is studied in pp collisions at sqrt(s)=7 TeV with the CMS experiment at the LHC. The measurement is based on a dimuon sample corresponding to an integrated luminosity of 314 inverse nanobarns. The J/psi differential cross section is determined, as a function of the J/psi transverse momentum, in three rapidity ranges. A fit to the decay length distribution is used to separate the prompt from the non-prompt (b hadron to J/psi) component. Integrated over J/psi transverse momentum from 6.5 to 30 GeV/c and over rapidity in the range |y| < 2.4, the measured cross sections, times the dimuon decay branching fraction, are 70.9 \pm 2.1 (stat.) \pm 3.0 (syst.) \pm 7.8(luminosity) nb for prompt J/psi mesons assuming unpolarized production and 26.0 \pm 1.4 (stat.) \pm 1.6 (syst.) \pm 2.9 (luminosity) nb for J/psi mesons from b-hadron decays.

13 data tables

Total cross section within the kinematic limits for prompt and non-prompt J/PSI production times branching ratio into MU+ MU-, assuming zero polarizartion. The second systematic error is the luminosity uncertainty.

Differential inclusive cross J/PSI section for the |rapidity| range 0 to 1.2 for each prompt J/PSI polarization scenario considered.

Differential inclusive cross J/PSI section for the |rapidity| range 1.2 to 1.6 for each prompt J/PSI polarization scenario considered.

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