Date

Rapidity dependence of antideuteron coalescence in pp collisions at $\sqrt{s}$ = 13 TeV with ALICE

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Agarwal, Apar ; et al.
CERN-EP-2024-187, 2024.
Inspire Record 2807680 DOI 10.17182/hepdata.156190

The production yields of antideuterons and antiprotons are measured in pp collisions at a center-of-mass energy of $\sqrt{s}=13$ TeV, as a function of transverse momentum ($p_{\rm T}$) and rapidity ($y$), for the first time up to $|y|= 0.7$. The measured spectra are used to study the $p_{\rm T}$ and rapidity dependence of the coalescence parameter $B_2$, which quantifies the coalescence probability of antideuterons. The $p_{\rm T}$ and rapidity dependence of the obtained $B_2$ is extrapolated for $p_{\rm T}> 1.7$ GeV/$c$ and $|y|>0.7$ using the phenomenological antideuteron production model implemented in PYTHIA 8.3 as well as a baryon coalescence afterburner model based on EPOS 3. Such measurements are of interest to the astrophysics community, since they can be used for the calculation of the flux of antinuclei from cosmic rays, in combination with coalescence models.

28 data tables

Transverse momentum spectra of antideuterons measured in pp collisions at centre-of-mass per nucleon-nucleon energy of 13 TeV, as shown in Fig. 1 (right panel). Rapidity interval 0 to 0.1.

Transverse momentum spectra of antideuterons measured in pp collisions at centre-of-mass per nucleon-nucleon energy of 13 TeV, as shown in Fig. 1 (right panel). Rapidity interval 0.1 to 0.2.

Transverse momentum spectra of antideuterons measured in pp collisions at centre-of-mass per nucleon-nucleon energy of 13 TeV, as shown in Fig. 1 (right panel). Rapidity interval 0.2 to 0.3.

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Measurement of the production and elliptic flow of (anti)nuclei in Xe-Xe collisions at $\sqrt{s_{\rm NN}}$ = 5.44 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Agarwal, Apar ; et al.
Phys.Rev.C 110 (2024) 064901, 2024.
Inspire Record 2791620 DOI 10.17182/hepdata.155473

Measurements of (anti)deuteron and (anti)$^3$He production in the rapidity range $ |y| < $ 0.5 as a function of the transverse momentum and event multiplicity in Xe$-$Xe collisions at a center-of-mass energy per nucleon$-$nucleon pair of $\sqrt{s_{\rm NN}}$ = 5.44 TeV are presented. The coalescence parameters $B_2$ and $B_3$ are measured as a function of the transverse momentum per nucleon. The ratios between (anti)deuteron and (anti)$^3$He yields and those of (anti)protons and pions are reported as a function of the mean charged-particle multiplicity density, and compared with two implementations of the statistical hadronization model and with coalescence predictions. The elliptic flow of (anti)deuterons is measured for the first time in Xe$-$Xe collisions and shows features similar to those already observed in Pb$-$Pb collisions, i.e., the mass ordering at low transverse momentum and the meson$-$baryon grouping at intermediate transverse momentum. The production of nuclei is particularly sensitive to the chemical freeze-out temperature of the system created in the collision, which is extracted from a grand-canonical-ensemble-based thermal fit, performed for the first time including light nuclei along with light-flavor hadrons in Xe$-$Xe collisions. The extracted chemical freeze-out temperature $T_{\rm chem}$ = (154.2 $\pm$ 1.1) MeV in Xe$-$Xe collisions is similar to that observed in Pb$-$Pb collisions and close to the crossover temperature predicted by lattice quantum chromodynamics calculations.

19 data tables

Transverse momentum spectra of 3He nuclei measured in Xe--Xe collisions at centre-of-mass per nucleon-nucleon energy of 5.44 TeV, as shown in Fig. 3 (right panel).

Transverse momentum spectra of deuterons measured in Xe--Xe collisions at centre-of-mass per nucleon-nucleon energy of 5.44 TeV, as shown in Fig. 3 (left panel). Centrality class 0 to 10 percent.

Transverse momentum spectra of deuterons measured in Xe--Xe collisions at centre-of-mass per nucleon-nucleon energy of 5.44 TeV, as shown in Fig. 3 (left panel). Centrality class 10 to 20 percent.

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Observation of abnormal suppression of $\mathrm{f}_{0}$(980) production in p$-$Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Aglieri Rinella, Gianluca ; et al.
Phys.Lett.B 853 (2024) 138665, 2024.
Inspire Record 2724206 DOI 10.17182/hepdata.151390

The dependence of $\mathrm{f}_{0}$(980) production on the final-state charged-particle multiplicity in p$-$Pb collisions at $\sqrt{s_{\mathrm{NN}}} = 5.02$ TeV is reported. The production of $\mathrm{f}_{0}$(980) is measured with the ALICE detector via the $\mathrm{f}_0 (980) \rightarrow \pi^{+}\pi^{-}$ decay channel in a midrapidity region of $-0.5<y<0$. Particle yield ratios of $\mathrm{f}_{0}$(980) to $\pi$ and $\mathrm{K}^{*}$(892)$^{0}$ are found to be decreasing with increasing charged-particle multiplicity. The magnitude of the suppression of the $\mathrm{f}_{0}$(980)/$\pi$ and $\mathrm{f}_{0}$(980)/$\mathrm{K}^{*}$(892)$^{0}$ yield ratios is found to be dependent on the transverse momentum $p_{\mathrm{T}}$, suggesting different mechanisms responsible for the measured effects. Furthermore, the nuclear modification factor $Q_{\mathrm{pPb}}$ of $\mathrm{f}_{0}$(980) is measured in various multiplicity ranges. The $Q_{\mathrm{pPb}}$ shows a strong suppression of the $\mathrm{f}_{0}$(980) production in the $p_{\mathrm{T}}$ region up to about 4 GeV/$c$. The results on the particle yield ratios and $Q_{\mathrm{pPb}}$ for $\mathrm{f}_{0}$(980) may help to understand the late hadronic phase in p$-$Pb collisions and the nature of the internal structure of $\mathrm{f}_{0}$(980) particle.

7 data tables

Transverse momentum spectra in different multiplicity classes. Each spectrum is corrected for the branching ratio of (46 $\pm$ 6)% based on [Phys. Rev. Lett. 111 no. 6, (2013) 062001].

The ratio of transverse momentum spectrum to the NSD spectrum

The double ratio of particle yield of f0((980) to charged pions

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Jet structure from dihadron correlations in d + Au collisions at s(NN)**(1/2) = 200-GeV.

The PHENIX collaboration Adler, S.S. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.C 73 (2006) 054903, 2006.
Inspire Record 694429 DOI 10.17182/hepdata.151167

Dihadron correlations at high transverse momentum in d+Au collisions at sqrt(s_NN) = 200 GeV at midrapidity are measured by the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC). From these correlations we extract several structural characteristics of jets; the root-mean-squared (RMS) transverse momentum of fragmenting hadrons with respect to the jet sqrt(<j_T^2>), the mean sine-squared angle between the scattered partons <sin^2(phi_jj)>, and the number of particles produced within the dijet that are associated with a high-p_T particle (dN/dx_E distributions). We observe that the fragmentation characteristics of jets in d+Au collisions are very similar to those in p+p collisions and that there is also little dependence on the centrality of the d+Au collision. This is consistent with the nuclear medium having little influence on the fragmentation process. Furthermore, there is no statistically significant increase in the value of <sin^2(phi_jj)> from p+p to d+Au collisions. This constrains the amount of multiple scattering that partons undergo in the cold nuclear medium before and after a hard-collision.

46 data tables

Measured $\gamma\gamma$ invariant mass distribution for 6 < $p_T$ < 7 GeV/$c$ in central $d$+Au collisions.

The comparison of near-side yield, near-side width, far-side yield, and far-side width as a function of $p_T$ of charged hadrons. These are obtained for $\pi^{\pm}$ - $h^{\pm}$ correlation from PYTHIA, with a trigger pion of 6 - 10 GeV/$c$.

Fully corrected assorted charged pion-hadron conditional pair distributions for $d$+Au collisions centrality 0-80% and $p$+$p$ collisions. The trigger $\pi^{\pm}$s are within 5 < $p_{T,trig}$ < 10 GeV/$c$ and are correlated with hadrons with $p_{T,assoc}$ 0.4-1.0 GeV/$c$, 1.0-2.0 GeV/$c$, 2.0-3.0 GeV/$c$, and 3.0-5.0 GeV/$c$.

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Measurement of long-range angular correlations and azimuthal anisotropies in high-multiplicity $p+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV

The PHENIX collaboration Aidala, C. ; Akiba, Y. ; Alfred, M. ; et al.
Phys.Rev.C 95 (2017) 034910, 2017.
Inspire Record 1486072 DOI 10.17182/hepdata.145924

We present the first measurements of long-range angular correlations and the transverse momentum dependence of elliptic flow $v_2$ in high-multiplicity $p$$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV. A comparison of these results with previous measurements in high-multiplicity $d$$+$Au and $^3{\rm He}$$+$Au collisions demonstrates a relation between $v_2$ and the initial collision eccentricity $\varepsilon_2$, suggesting that the observed momentum-space azimuthal anisotropies in these small systems have a collective origin and reflect the initial geometry. Good agreement is observed between the measured $v_2$ and hydrodynamic calculations for all systems, and an argument disfavoring theoretical explanations based on momentum-space domain correlations is presented. The set of measurements presented here allows us to leverage the distinct intrinsic geometry of each of these systems to distinguish between different theoretical descriptions of the long-range correlations observed in small collision systems.

2 data tables

The ratio of the two harmonics ($\Sigma Q^{BBC-S}$)$_{p+p}$/($\Sigma Q^{BBC-S}$)$_{pAu}$.

$v_2$ of charged hadrons within $|\eta|$ < 0.35 in 0-5% $p$+Au central collisions, compared to hydrodynamic calculations using the SONIC model, matched to the same multiplicity as the data.


Absence of suppression in particle production at large transverse momentum in s(NN)**(1/2) = 200-GeV d + Au collisions.

The PHENIX collaboration Adler, S.S. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.Lett. 91 (2003) 072303, 2003.
Inspire Record 621391 DOI 10.17182/hepdata.143668

Transverse momentum spectra of charged hadrons with p_T < 8 GeV/c and neutral pions with p_T < 10 GeV/c have been measured at mid-rapidity by the PHENIX experiment at RHIC in d+Au collisions at sqrt(s_NN) = 200 GeV. The measured yields are compared to those in p+p collisions at the same sqrt(s_NN) scaled up by the number of underlying nucleon-nucleon collisions in d+Au. The yield ratio does not show the suppression observed in central Au+Au collisions at RHIC. Instead, there is a small enhancement in the yield of high momentum particles.

10 data tables

Midrapidity $p_T$ spectra for charged hadrons.

Midrapidity $p_T$ spectra for $\pi^0$.

Nuclear modification factor $R_{dA}$ for $\pi^0$ in the PbGl and PbSc calorimeters in minimum bias $d$+$Au$.

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Systematic Studies of Elliptic Flow Measurements in Au+Au Collisions at sqrt(s_NN) = 200 GeV

The PHENIX collaboration Afanasiev, S. ; Aidala, C. ; Ajitanand, N.N. ; et al.
Phys.Rev.C 80 (2009) 024909, 2009.
Inspire Record 819672 DOI 10.17182/hepdata.143606

We present inclusive charged hadron elliptic flow v_2 measured over the pseudorapidity range |\eta| < 0.35 in Au+Au collisions at sqrt(s_NN) = 200 GeV. Results for v_2 are presented over a broad range of transverse momentum (p_T = 0.2-8.0 GeV/c) and centrality (0-60%). In order to study non-flow effects that are not correlated with the reaction plane, as well as the fluctuations of v_2, we compare two different analysis methods: (1) event plane method from two independent sub-detectors at forward (|\eta| = 3.1-3.9) and beam (|\eta| > 6.5) pseudorapidities and (2) two-particle cumulant method extracted using correlations between particles detected at midrapidity. The two event-plane results are consistent within systematic uncertainties over the measured p_T and in centrality 0-40%. There is at most 20% difference of the v_2 between the two event plane methods in peripheral (40-60%) collisions. The comparisons between the two-particle cumulant results and the standard event plane measurements are discussed.

23 data tables

Centrality classes and average number of participant nucleons $\langle N_{part} \rangle$ obtained from a Glauber Monte Carlo simulation of the BBC and ZDC responses for Au+Au collision at $\sqrt{s_{NN}}$ = 200 GeV.

Comparison of Res{$\Psi_n$;X} and Res{$\Psi_n$;Y} with Res{$\Psi_n$} for the BBC event plane and ZDC-SMD event plane as a function of centrality.

Charged hadron $v_2$($p_T$) in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV from the two-particle cumulant method, the BBC event plane, and the ZDC-SMD event plane for the indicated centralities.

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Charged hadron multiplicity fluctuations in Au+Au and Cu+Cu collisions from sqrt(s_NN) = 22.5 to 200 GeV

The PHENIX collaboration Adare, A. ; Adler, S.S. ; Afanasiev, S. ; et al.
Phys.Rev.C 78 (2008) 044902, 2008.
Inspire Record 785509 DOI 10.17182/hepdata.143616

A comprehensive survey of event-by-event fluctuations of charged hadron multiplicity in relativistic heavy ions is presented. The survey covers Au+Au collisions at sqrt(s_NN) = 62.4 and 200 GeV, and Cu+Cu collisions sqrt(s_NN) = 22.5, 62.4, and 200 GeV. Fluctuations are measured as a function of collision centrality, transverse momentum range, and charge sign. After correcting for non-dynamical fluctuations due to fluctuations in the collision geometry within a centrality bin, the remaining dynamical fluctuations expressed as the variance normalized by the mean tend to decrease with increasing centrality. The dynamical fluctuations are consistent with or below the expectation from a superposition of participant nucleon-nucleon collisions based upon p+p data, indicating that this dataset does not exhibit evidence of critical behavior in terms of the compressibility of the system. An analysis of Negative Binomial Distribution fits to the multiplicity distributions demonstrates that the heavy ion data exhibit weak clustering properties.

86 data tables

Additional information containing number of events which were used to reconstruct the numvers matching to Figure 1 and 2.

Additional information containing number of events which were used to reconstruct the numvers matching to Figure 1 and 2.

Additional information containing number of events which were used to reconstruct the numvers matching to Figure 1 and 2.

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Correlated production of p and anti-p in Au + Au collisions at s(NN)**(1/2) = 200-GeV.

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Lett.B 649 (2007) 359-369, 2007.
Inspire Record 731666 DOI 10.17182/hepdata.143520

Correlations between p and pbar's at transverse momenta typical of enhanced baryon production in Au+Au collisions are reported. The PHENIX experiment measures same and opposite sign baryon pairs in Au+Au collisions at sqrt(s_NN) = 200 GeV. Correlated production of p and p^bar with the trigger particle from the range 2.5 < p_T < 4.0 GeV/c and the associated particle with 1.8 < p_T < 2.5 GeV/c is observed to be nearly independent of the centrality of the collisions. Same sign pairs show no correlation at any centrality. The conditional yield of mesons triggered by baryons (and anti-baryons) and mesons in the same pT range rises with increasing centrality, except for the most central collisions, where baryons show a significantly smaller number of associated mesons. These data are consistent with a picture in which hard scattered partons produce correlated p and p^bar in the p_T region of the baryon excess.

9 data tables

$1/{N_{trig}}$ ${dN}/{d\Delta\phi}$ distributions for charge-inclusive baryon triggers and associated particles for six centrality bins. Triggers have 2.5 < $p_T$ < 4.0 GeV/$c$ and associated particles have 1.8 < $p_T$ < 2.5 GeV/$c$.

$1/{N_{trig}}$ ${dN}/{d\Delta\phi}$ distributions for charge selected $\bar{p}$ and $p$ triggers both with associated $p$ for six centrality bins. Triggers have 2.5 < $p_T$ < 4.0 GeV/$c$ and associated particles have 1.8 < $p_T$ < 2.5 GeV/$c$.

$1/{N_{trig}}$ ${dN}/{d\Delta\phi}$ distributions for charge selected $\bar{p}$ and $p$ triggers both with associated $p$ for six centrality bins. Triggers have 2.5 < $p_T$ < 4.0 GeV/$c$ and associated particles have 1.8 < $p_T$ < 2.5 GeV/$c$.

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Measurement of non-random event-by-event fluctuations of average transverse momentum in s**(1/2) = 200-GeV Au + Au and p + p collisions.

The PHENIX collaboration Adler, S.S. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.Lett. 93 (2004) 092301, 2004.
Inspire Record 630161 DOI 10.17182/hepdata.143470

Event-by-event fluctuations of the average transverse momentum of produced particles near mid-rapidity have been measured by the PHENIX Collaboration in sqrt(s_NN)=200 GeV Au+Au and p+p collisions at the Relativistic Heavy Ion Collider. The fluctuations are observed to be in excess of the expectation for statistically independent particle emission for all centralities. The excess fluctuations exhibit a dependence on both the centrality of the collision and on the transverse momentum window over which the average is calculated. Both the centrality and p_T dependence can be well reproduced by a simulation of random particle production with the addition of contributions from hard scattering processes.

4 data tables

Comparisons between the data and mixed event $M_{p_T}$ distributions for the representative 0-5% centrality classes. Also given are the residuals between the data and mixed events in units of standard deviations of the data points form the mixed event points.

Comparisons between the data and mixed event $M_{p_T}$ distributions for the representative 30-35% centrality classes. Also given are the residuals between the data and mixed events in units of standard deviations of the data points form the mixed event points.

$F_{p_T}$ (in percent, 0.2 GeV/$c$ < $p_T$ < 2.0 GeV/$c$) as a function of centrality, which is expressed in terms of the number of participants in the collision, $N_{part}$.

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Scaling properties of azimuthal anisotropy in Au + Au and Cu + Cu collisions at s(NN)**(1/2) = 200-GeV.

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.Lett. 98 (2007) 162301, 2007.
Inspire Record 723948 DOI 10.17182/hepdata.143460

Detailed differential measurements of the elliptic flow for particles produced in Au+Au and Cu+Cu collisions at sqrt(s_NN) = 200 GeV are presented. Predictions from perfect fluid hydrodynamics for the scaling of the elliptic flow coefficient v_2 with eccentricity, system size and transverse energy are tested and validated. For transverse kinetic energies KE_T ~ m_T-m up to ~1 GeV, scaling compatible with the hydrodynamic expansion of a thermalized fluid is observed for all produced particles. For large values of KE_T, the mesons and baryons scale separately. A universal scaling for the flow of both mesons and baryons is observed for the full transverse kinetic energy range of the data when quark number scaling is employed. In both cases the scaling is more pronounced in terms of KE_T rather than transverse momentum.

15 data tables

$v_2$ vs. $p_T$ for charged hadrons for Au+Au collisions.

$v_2$ vs. $p_T$ for charged hadrons for Cu+Cu collisions.

$v_2$ vs. $p_T$ for charged hadrons. divided by $k$ times ($k = 3.1$) the $p_T$-integrated $v_2$ (centrality) for Au+Au and Cu+Cu collisions.

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J/psi suppression at forward rapidity in Au+Au collisions at sqrt(s_NN)=39 and 62.4 GeV

The PHENIX collaboration Adare, A. ; Aidala, C. ; Ajitanand, N.N. ; et al.
Phys.Rev.C 86 (2012) 064901, 2012.
Inspire Record 1127261 DOI 10.17182/hepdata.143112

We present measurements of the J/psi invariant yields in sqrt(s_NN)=39 and 62.4 GeV Au+Au collisions at forward rapidity (1.2<|y|<2.2). Invariant yields are presented as a function of both collision centrality and transverse momentum. Nuclear modifications are obtained for central relative to peripheral Au+Au collisions (R_CP) and for various centrality selections in Au+Au relative to scaled p+p cross sections obtained from other measurements (R_AA). The observed suppression patterns at 39 and 62.4 GeV are quite similar to those previously measured at 200 GeV. This similar suppression presents a challenge to theoretical models that contain various competing mechanisms with different energy dependencies, some of which cause suppression and others enhancement.

7 data tables

Estimates used for the 39- and 62.4-GeV $J/\psi$ $p$+$p$ cross sections along with their uncertainties.

$J/\psi$ invariant yields are shown for Au+Au collisions at 39 and 62.4 GeV as a function of the number of participating nucleons.

$J/\psi$ invariant yields are shown for Au+Au collisions at 39 and 62.4 GeV as a function of the number of participating nucleons.

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Measurement of neutral mesons in p+p collisions at sqrt(s) = 200 GeV and scaling properties of hadron production

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.D 83 (2011) 052004, 2011.
Inspire Record 855102 DOI 10.17182/hepdata.143371

The PHENIX experiment at the Relativistic Heavy Ion Collider has measured the invariant differential cross section for production of K^0_S , \omega, \eta prime, and \phi mesons in p + p collisions at = 200 GeV. Measurements \omega and \phi production in different decay channels give consistent results. New results for the \phi are in agreement with previously published data and extend the measured pT coverage. The spectral shapes of all hadron transverse momentum distributions measured by PHENIX are well described by a Tsallis distribution functional form with only two parameters, n and T, determining the high-pT and characterizing the low-pT regions of the spectra, respectively. The values of these parameters are very similar for all analyzed meson spectra, but with a lower parameter T extracted for protons. The integrated invariant cross sections calculated from the fitted distributions are found to be consistent with existing measurements and with statistical model predictions.

15 data tables

Parameters of the Tsallis fit with Eq. 8 in the paper with all parameters free to vary. Cross sections are in $\mu$b for $J/\psi$ and $\psi^{\prime}$ and in mb for all other particles.

Parameters of the power law fit with Eq. 3 in the paper. Units of $A$ are mb(GeV/$c$)$^{\upsilon + 2}$.

Constant and linear fits to the power law and Tsallis fit parameters. The last column (Prob.) gives the probability estimated by the $\chi^2$/$n.d.f.$ of the fit.

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Azimuthally anisotropic emission of low-momentum direct photons in Au$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.C 94 (2016) 064901, 2016.
Inspire Record 1394895 DOI 10.17182/hepdata.143116

The PHENIX experiment at the Relativistic Heavy Ion Collider has measured 2nd and 3rd order Fourier coefficients of the azimuthal distributions of direct photons emitted at midrapidity in Au$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV for various collision centralities. Combining two different analysis techniques, results were obtained in the transverse momentum range of $0.4<p_{T}<4.0$ GeV/$c$. At low $p_T$ the second-order coefficients, $v_2$, are similar to the ones observed in hadrons. Third order coefficients, $v_3$, are nonzero and almost independent of centrality. These new results on $v_2$ and $v_3$, combined with previously published results on yields, are compared to model calculations that provide yields and asymmetries in the same framework. Those models are challenged to explain simultaneously the observed large yield and large azimuthal anisotropies.

2 data tables

Direct photon $v_2$ and $v_3$ at midrapidity ($|\eta|$ < 0.35), for different centralities, measured with the conversion method. The event plane was determined with the reaction plane detector (1 < $|\eta|$ < 2.8).

Direct photon $v_2$ and $v_3$ at midrapidity ($|\eta|$ < 0.35), for different centralities, measured with the calorimeter method. The event plane was determined with the reaction plane detector (1 < $|\eta|$ < 2.8).


Elliptic and hexadecapole flow of charged hadrons in Au+Au collisions at sqrt(s_NN) = 200 GeV

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.Lett. 105 (2010) 062301, 2010.
Inspire Record 850211 DOI 10.17182/hepdata.143006

Differential measurements of the elliptic (v_2) and hexadecapole (v_4) Fourier flow coefficients are reported for charged hadrons as a function of transverse momentum (p_T) and collision centrality or the number of participant nucleons (N_part) for Au+Au collisions at sqrt(s_NN)=200 GeV. The v_{2,4} measurements at pseudorapidity |\eta|<=0.35 obtained with four separate reaction plane detectors positioned in the range 1.0<|\eta|<3.9 show good agreement, indicating the absence of significant \eta-dependent nonflow perturbations. Sizable values for v_4(p_T) are observed with a ratio v_4(p_T,N_part)/v_2^2(p_T,N_part)~0.8 for 50<N_part<200, which is compatible with the combined effects of a finite viscosity and initial eccentricity fluctuations. For N_part>200 this ratio increases up to 1.7 in the most central collisions.

7 data tables

Glauber quantities ($N_{part}$, $N_{coll}$, $b$) for Au+Au collisions at 200 GeV (PHENIX Run 2007)

Event-plane resolution factors vs. $N_{part}$ for $v_2$ and $v_4$ measurements for the indicated event planes.

Comparison of $v_2$ vs. $N_{part}$ and $v_4$ vs. $N_{part}$ for charged hadrons obtained with several reaction plane detectors for the $p_T$ selections indicated.

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Dielectron production in Au$+$Au collisions at $\sqrt{s_{NN}}$=200 GeV

The PHENIX collaboration Adare, A. ; Aidala, C. ; Ajitanand, N.N. ; et al.
Phys.Rev.C 93 (2016) 014904, 2016.
Inspire Record 1393530 DOI 10.17182/hepdata.143067

We present measurements of $e^+e^-$ production at midrapidity in Au$+$Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV. The invariant yield is studied within the PHENIX detector acceptance over a wide range of mass ($m_{ee} <$ 5 GeV/$c^2$) and pair transverse momentum ($p_T$ $<$ 5 GeV/$c$), for minimum bias and for five centrality classes. The \ee yield is compared to the expectations from known sources. In the low-mass region ($m_{ee}=0.30$--0.76 GeV/$c^2$) there is an enhancement that increases with centrality and is distributed over the entire pair \pt range measured. It is significantly smaller than previously reported by the PHENIX experiment and amounts to $2.3\pm0.4({\rm stat})\pm0.4({\rm syst})\pm0.2^{\rm model}$ or to $1.7\pm0.3({\rm stat})\pm0.3({\rm syst})\pm0.2^{\rm model}$ for minimum bias collisions when the open-heavy-flavor contribution is calculated with {\sc pythia} or {\sc mc@nlo}, respectively. The inclusive mass and $p_T$ distributions as well as the centrality dependence are well reproduced by model calculations where the enhancement mainly originates from the melting of the $\rho$ meson resonance as the system approaches chiral symmetry restoration. In the intermediate-mass region ($m_{ee}$ = 1.2--2.8 GeV/$c^2$), the data hint at a significant contribution in addition to the yield from the semileptonic decays of heavy-flavor mesons.

2 data tables

Cocktail of hadronic sources for the 2010 run using the PYTHIA generator for the open heavy flavor contributions.

Invariant mass spectrum of $e^+e^-$ pairs in MB Au+Au collisions within the PHENIX acceptance compared to the cocktail of expected decays.


High p(T) charged hadron suppression in Au + Au collisions at s(NN)**1/2 = 200-GeV

The PHENIX collaboration Adler, S.S. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.C 69 (2004) 034910, 2004.
Inspire Record 625472 DOI 10.17182/hepdata.142939

The PHENIX experiment at RHIC has measured charged hadron yields at mid-rapidity over a wide range of transverse momentum (0.5 < p_T < 10 GeV/c) in Au+Au collisions at sqrt(s_NN)=200 GeV. The data are compared to pi^zero measurements from the same experiment. For both charged hadrons and neutral pions, the yields per nucleon-nucleon collision are significantly suppressed in central compared to peripheral and nucleon-nucleon collisions. The suppression sets in gradually and increases with increasing centrality of the collisions. Above 4-5 GeV/c in p_T, a constant and almost identical suppression of charged hadrons and pi^zeroes is observed. The p_T spectra are compared to published spectra from Au+Au at sqrt(s_NN)=130 in terms of x_t scaling. Central and peripheral pi^zero as well as peripheral charged spectra exhibit the same x_t scaling as observed in p+p data.

19 data tables

$p_T$ spectra of charged hadrons for minimum bias collisions along with spectra for 9 centrality classes derived from the pseudo-rapidity region $|\eta|$ < 0.18. Stat. stands for statistical error, syst. stands for the systematic errors and occ. stands for occupancy error.

$p_T$ spectra of charged hadrons for minimum bias collisions along with spectra for 9 centrality classes derived from the pseudo-rapidity region $|\eta|$ < 0.18. Stat. stands for statistical error, syst. stands for the systematic errors and occ. stands for occupancy error.

$p_T$ spectra of charged hadrons for minimum bias collisions along with spectra for 9 centrality classes derived from the pseudo-rapidity region $|\eta|$ < 0.18. Stat. stands for statistical error, syst. stands for the systematic errors and occ. stands for occupancy error.

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Onset of $\pi^0$ Suppression Studied in Cu$+$Cu Collisions at $\sqrt{s_{NN}}=$22.4, 62.4, and 200 GeV

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.Lett. 101 (2008) 162301, 2008.
Inspire Record 778403 DOI 10.17182/hepdata.143005

Neutral pion transverse momentum (pT) spectra at mid-rapidity (|y| < 0.35) were measured in Cu+Cu collisions at \sqrt s_NN = 22.4, 62.4, and 200 GeV. Relative to pi -zero yields in p+p collisions scaled by the number of inelastic nucleon-nucleon collisions (Ncoll) at the respective energies, the pi-zero yields for pT \ge 2 GeV/c in central Cu+Cu collisions at 62.4 and 200 GeV are suppressed, whereas an enhancement is observed at 22.4 GeV. A comparison with a jet quenching model suggests that final state parton energy loss dominates in central Cu+Cu collisions at 62.4 GeV and 200 GeV, while the enhancement at 22.4 GeV is consistent with nuclear modifications in the initial state alone.

9 data tables

Invariant $\pi^0$ yields in central Cu+Cu collisions and invariant $\pi^0$ cross sections in $p$+$p$ collisions at $\sqrt{s_{NN}}$ = 22.4 GeV. The error (tot.) includes the quadratic sum of the statistical and total systematic uncertainties.

Invariant $\pi^0$ yields in central Cu+Cu collisions and invariant $\pi^0$ cross sections in $p$+$p$ collisions at $\sqrt{s_{NN}}$ = 62.4 GeV. The error (tot.) includes the quadratic sum of the statistical and total systematic uncertainties.

Invariant $\pi^0$ yields in central Cu+Cu collisions and invariant $\pi^0$ cross sections in $p$+$p$ collisions at $\sqrt{s_{NN}}$ = 200 GeV. The error (tot.) includes the quadratic sum of the statistical and total systematic uncertainties.

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System size and energy dependence of jet-induced hadron pair correlation shapes in Cu + Cu and Au + Au collisions at s(NN)**(1/2) = 200-GeV and 62.4-GeV.

The PHENIX collaboration Adare, A. ; Adler, S.S. ; Afanasiev, S. ; et al.
Phys.Rev.Lett. 98 (2007) 232302, 2007.
Inspire Record 731669 DOI 10.17182/hepdata.142605

We present azimuthal angle correlations of intermediate transverse momentum (1-4 GeV/c) hadrons from {dijets} in Cu+Cu and Au+Au collisions at sqrt(s_NN) = 62.4 and 200 GeV. The away-side dijet induced azimuthal correlation is broadened, non-Gaussian, and peaked away from \Delta\phi=\pi in central and semi-central collisions in all the systems. The broadening and peak location are found to depend upon the number of participants in the collision, but not on the collision energy or beam nuclei. These results are consistent with sound or shock wave models, but pose challenges to Cherenkov gluon radiation models.

6 data tables

The measured correlation $C(\Delta\phi)$ and the dijet correlation $J(\Delta\phi)$ in central Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV.

Dijet correlations in Au+Au and Cu+Cu collisions at $\sqrt{s_{NN}}$ = 62.4 and 200 GeV.

Dijet correlations in Au+Au and Cu+Cu collisions at $\sqrt{s_{NN}}$ = 62.4 and 200 GeV.

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Flow measurements via two-particle azimuthal correlations in Au + Au collisions at s(NN)**(1/2) = 130-GeV.

The PHENIX collaboration Adcox, K. ; Adler, S.S. ; Ajitanand, N.N. ; et al.
Phys.Rev.Lett. 89 (2002) 212301, 2002.
Inspire Record 585347 DOI 10.17182/hepdata.141931

Two particle azimuthal correlation functions are presented for charged hadrons produced in Au + Au collisions at RHIC sqrt(s_NN) = 130 GeV. The measurements permit determination of elliptic flow without event-by-event estimation of the reaction plane. The extracted elliptic flow values v_2 show significant sensitivity to both the collision centrality and the transverse momenta of emitted hadrons, suggesting rapid thermalization and relatively strong velocity fields. When scaled by the eccentricity of the collision zone, epsilon, the scaled elliptic flow shows little or no dependence on centrality for charged hadrons with relatively low p_T. A breakdown of this epsilon scaling is observed for charged hadrons with p_T > 1.0 GeV/c for the most central collisions.

8 data tables

Azimuthal correlation functions for charged hadrons as a function of centrality and $p_T$ selection. The solid curves represent Fourier fits following Eq. (2). Error bars are statistical only.

$v_2$ vs. centrality for several $p_T$ selections. [F] and [A] indicate results obtained with the fixed-$p_T$ and assorted-$p_T$ methods respectively. Systematic errors are estimated to be $\sim 5$%; they are dominated by the normalization of the correction function for real tracks. For the centrality range 0-5%, the data points are statistically uncertain and the points are omitted.

$v_2$ vs. centrality for several $p_T$ selections. [F] and [A] indicate results obtained with the fixed-$p_T$ and assorted-$p_T$ methods respectively. Systematic errors are estimated to be $\sim 5$%; they are dominated by the normalization of the correction function for real tracks. For the centrality range 0-5%, the data points are statistically uncertain and the points are omitted.

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Deviation from quark-number scaling of the anisotropy parameter v_2 of pions, kaons, and protons in Au+Au collisions at sqrt(s_NN) = 200 GeV

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.C 85 (2012) 064914, 2012.
Inspire Record 1093596 DOI 10.17182/hepdata.141645

Measurements of the anisotropy parameter v_2 of identified hadrons (pions, kaons, and protons) as a function of centrality, transverse momentum p_T, and transverse kinetic energy KE_T at midrapidity (|\eta|<0.35) in Au+Au collisions at sqrt(s_NN) = 200 GeV are presented. Pions and protons are identified up to p_T = 6 GeV/c, and kaons up to p_T = 4 GeV/c, by combining information from time-of-flight and aerogel Cherenkov detectors in the PHENIX Experiment. The scaling of v_2 with the number of valence quarks (n_q) has been studied in different centrality bins as a function of transverse momentum and transverse kinetic energy. A deviation from previously observed quark-number scaling is observed at large values of KE_T/n_q in noncentral Au+Au collisions (20--60%), but this scaling remains valid in central collisions (0--10%).

21 data tables

Identified hadron $v_2$ in central (0–20% centrality, left panels) Au + Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. Panels (a) and (b) show $v_2$ as a function of transverse momentum $p_T$. The $v_2$ of all species for centrality 0–20% has been scaled up by a factor of 1.6 for better comparison with results of 20–60% centrality. The error bars (shaded boxes) represent the statistical (systematic) uncertainties. The systematic uncertainties shown are type A and B only.

Identified hadron $v_2$ in central (0–20% centrality, left panels) Au + Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. Panels (a) and (b) show $v_2$ as a function of transverse momentum $p_T$. The $v_2$ of all species for centrality 0–20% has been scaled up by a factor of 1.6 for better comparison with results of 20–60% centrality. The error bars (shaded boxes) represent the statistical (systematic) uncertainties. The systematic uncertainties shown are type A and B only.

Identified hadron $v_2$ in central (0–20% centrality, left panels) Au + Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. Panels (a) and (b) show $v_2$ as a function of transverse momentum $p_T$. The $v_2$ of all species for centrality 0–20% has been scaled up by a factor of 1.6 for better comparison with results of 20–60% centrality. The error bars (shaded boxes) represent the statistical (systematic) uncertainties. The systematic uncertainties shown are type A and B only.

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Nuclear effects on hadron production in d + Au and p + p collisions at s(NN)**(1/2) = 200-GeV.

The PHENIX collaboration Adler, S.S. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.C 74 (2006) 024904, 2006.
Inspire Record 711951 DOI 10.17182/hepdata.141892

PHENIX has measured the centrality dependence of mid-rapidity pion, kaon and proton transverse momentum distributions in d+Au and p+p collisions at sqrt(s_NN) = 200 GeV. The p+p data provide a reference for nuclear effects in d+Au and previously measured Au+Au collisions. Hadron production is enhanced in d+Au, relative to independent nucleon-nucleon scattering, as was observed in lower energy collisions. The nuclear modification factor for (anti) protons is larger than that for pions. The difference increases with centrality, but is not sufficient to account for the abundance of baryon production observed in central Au+Au collisions at RHIC. The centrality dependence in d+Au shows that the nuclear modification factor increases gradually with the number of collisions suffered by each participant nucleon. We also present comparisons with lower energy data as well as with parton recombination and other theoretical models of nuclear effects on particle production.

6 data tables

Mean number of binary collisions, particpating nucleons from the Au nucleus, number of collisions per participating deuteron nucleon, and trigger bias corrections for the $d$+Au centrality bins.

Transverse momentum in GeV/$c$ for $\pi^{\pm}$.

Transverse momentum in GeV/$c$ for $\pi^{\pm}$.

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Measurements of mass-dependent azimuthal anisotropy in central $p+$Au, $d+$Au, and $^3$He$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV

The PHENIX collaboration Adare, A. ; Aidala, C. ; Ajitanand, N.N. ; et al.
Phys.Rev.C 97 (2018) 064904, 2018.
Inspire Record 1632759 DOI 10.17182/hepdata.141812

We present measurements of the transverse-momentum dependence of elliptic flow $v_2$ for identified pions and (anti)protons at midrapidity ($|\eta|<0.35$), in 0%--5% central $p$$+$Au and $^3$He$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV. When taken together with previously published measurements in $d$$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV, the results cover a broad range of small-collision-system multiplicities and intrinsic initial geometries. We observe a clear mass-dependent splitting of $v_2(p_{T})$ in $d$$+$Au and $^3$He$+$Au collisions, just as in large nucleus-nucleus ($A$$+$$A$) collisions, and a smaller splitting in $p$$+$Au collisions. Both hydrodynamic and transport model calculations successfully describe the data at low $p_T$ ($< 1.5$ GeV/$c$), but fail to describe various features at higher $p_T$. In all systems, the $v_2$ values follow an approximate quark-number scaling as a function of the hadron transverse kinetic energy per constituent quark($KE_T/n_q$), which was also seen previously in $A$$+$$A$ collisions.

4 data tables

Values of $v_2$($p_T$) for kaons in central 0-5% $p$+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV.

Values of $v_2$($p_T$) for kaons in central 0-5% $^3$He+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV.

Transverse momentum dependence of $v_2$ for identified pions and protons within $|\eta|$ < 0.35 in 0-5% central $p$+Au collisions.

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Centrality dependence of pi0 and eta production at large transverse momentum in s(NN)**(1/2) = 200-GeV d + Au collisions.

The PHENIX collaboration Adler, S.S. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.Lett. 98 (2007) 172302, 2007.
Inspire Record 729950 DOI 10.17182/hepdata.141813

The dependence of transverse momentum spectra of neutral pions and eta mesons with p_T <16 GeV/c and p_T < 12 GeV/c, respectively, on the centrality of the collision has been measured at mid-rapidity by the PHENIX experiment at RHIC in d+Au collisions at sqrt(s_(NN)) = 200 GeV. The measured yields are compared to those in p + p collisions at the same sqrt(s_(NN)) scaled by the number of underlying nucleon-nucleon collisions in d+Au. At all centralities the yield ratios show no suppression, in contrast to the strong suppression seen for central Au+Au collisions at RHIC. Only a weak p_T and centrality dependence can be observed.

10 data tables

Invariant yields at mid-rapidity for $\pi^0$ and $\eta$ in $d$+Au collisions as a function of $p_T$ for different centrality selections.

Invariant yields at mid-rapidity for $\pi^0$ and $\eta$ in $d$+Au collisions as a function of $p_T$ for different centrality selections.

Invariant yields at mid-rapidity for $\pi^0$ and $\eta$ in $d$+Au collisions as a function of $p_T$ for different centrality selections.

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A detailed study of high-p(T) neutral pion suppression and azimuthal anisotropy in Au + Au collisions at s(NN)**(1/2) = 200-GeV.

The PHENIX collaboration Adler, S.S. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.C 76 (2007) 034904, 2007.
Inspire Record 731134 DOI 10.17182/hepdata.141853

Measurements of neutral pion production at midrapidity in sqrt(s_NN) = 200 GeV Au+Au collisions as a function of transverse momentum, p_T, collision centrality, and angle with respect to reaction plane are presented. The data represent the final pi^0 results from the PHENIX experiment for the first RHIC Au+Au run at design center-of-mass-energy. They include additional data obtained using the PHENIX Level-2 trigger with more than a factor of three increase in statistics over previously published results for p_T > 6 GeV/c. We evaluate the suppression in the yield of high-p_T pi^0's relative to point-like scaling expectations using the nuclear modification factor R_AA. We present the p_T dependence of R_AA for nine bins in collision centrality. We separately integrate R_AA over larger p_T bins to show more precisely the centrality dependence of the high-p_T suppression. We then evaluate the dependence of the high-p_T suppression on the emission angle \Delta\phi of the pions with respect to event reaction plane for 7 bins in collision centrality. We show that the yields of high-p_T pi^0's vary strongly with \Delta\phi, consistent with prior measurements. We show that this variation persists in the most peripheral bin accessible in this analysis. For the peripheral bins we observe no suppression for neutral pions produced aligned with the reaction plane while the yield of pi^0's produced perpendicular to the reaction plane is suppressed by more than a factor of 2. We analyze the combined centrality and \Delta\phi dependence of the pi^0 suppression in different p_T bins using different possible descriptions of parton energy loss dependence on jet path-length averages to determine whether a single geometric picture can explain the observed suppression pattern.

9 data tables

Neutral pion invariant yields as a function of $p_T$ measured in minimum bias and 9 centrality classes in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV.

Neutral pion invariant yields as a function of $p_T$ measured in minimum bias and 9 centrality classes in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV.

Neutral pion invariant yields as a function of $p_T$ measured in minimum bias and 9 centrality classes in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV.

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