Transverse mass dependence of two-pion 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. 88 (2002) 192302, 2002.
Inspire Record 581871 DOI 10.17182/hepdata.141647

Two-pion correlations in sqrt(s_NN)=130 GeV Au+Au collisions at RHIC have been measured over a broad range of pair transverse momentum k_T by the PHENIX experiment at RHIC. The k_T dependent transverse radii are similar to results from heavy ion collisions at sqrt(s_NN) = 4.1, 4.9, and 17.3 GeV, whereas the longitudinal radius increases monotonically with beam energy. The ratio of the outwards to sidewards transverse radii (R_out/R_side) is consistent with unity and independent of k_T.

6 data tables

HBT radii for pion pairs as a function of $k_T$ measured at mid-rapidity for various energies for Au+Au collisions at $\sqrt{s_{NN}}$ = 130 GeV. Values used are from the Longitudinal Co-Moving System (LCMS) frame.

HBT radii for pion pairs as a function of $k_T$ measured at mid-rapidity for various energies for Au+Au collisions at $\sqrt{s_{NN}}$ = 130 GeV. Values used are from the Pair Center-of-Mass System (PCMS) frame.

The top panel shows the measured $R_{side}$ from identical pions for PHENIX. The bottom panel shows the ratio $R_{out}/R_{side}$ as a function of $k_T$. Longitudinal Co-Moving System (LCMS) frame for $\pi^+$

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Transverse momentum dependence of meson suppression in Au+Au collisions at sqrt(s_NN) = 200 GeV

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.C 82 (2010) 011902, 2010.
Inspire Record 856259 DOI 10.17182/hepdata.106472

New measurements by the PHENIX experiment at RHIC for eta production at midrapidity as a function of transverse momentum (p_T) and collision centrality in sqrt(s_NN) = 200 GeV Au+Au and p+p collisions are presented. They indicate nuclear modification factors (R_AA) that are similar both in magnitude and trend to those found in earlier pi^0 measurements. Linear fits to R_AA in the 5--20 GeV/c p_T region show that the slope is consistent with zero within two standard deviations at all centralities although a slow rise cannot be excluded. Having different statistical and systematic uncertainties the pi^0 and eta measurements are complementary at high p_T/ thus, along with the extended p_T range of these data they can provide additional constraints for theoretical modeling and the extraction of transport properties.

25 data tables

$E\frac{dN^3}{dp^3}$ vs. $p_T$, 0% to 5% centrality $Au+Au$. 90% Limit on 18-20 and 20-22 GeV/c bins.

$E\frac{dN^3}{dp^3}$ vs. $p_T$, 0% to 10% centrality $Au+Au$. 90% Limit on 18-20 and 20-22 GeV/c bins.

$E\frac{dN^3}{dp^3}$ vs. $p_T$, 10% to 20% centrality $Au+Au$.

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Production of $\pi^0$ and $\eta$ mesons in Cu$+$Au collisions at $\sqrt{s_{_{NN}}}$=200 GeV

The PHENIX collaboration Aidala, C. ; Ajitanand, N.N. ; Akiba, Y. ; et al.
Phys.Rev.C 98 (2018) 054903, 2018.
Inspire Record 1672859 DOI 10.17182/hepdata.100192

Production of $\pi^0$ and $\eta$ mesons has been measured at midrapidity in Cu$+$Au collisions at $\sqrt{s_{_{NN}}}$=200 GeV. Measurements were performed in $\pi^0(\eta)\rightarrow\gamma\gamma$ decay channel in the 1(2)-20 GeV/$c$ transverse momentum range. A strong suppression is observed for $\pi^0$ and $\eta$ meson production at high transverse momentum in central Cu$+$Au collisions relative to the $p$$+$$p$ results scaled by the number of nucleon-nucleon collisions. In central collisions the suppression is similar to Au$+$Au with comparable nuclear overlap. The $\eta/\pi^0$ ratio measured as a function of transverse momentum is consistent with $m_T$-scaling parameterization down to $p_T=$2 GeV/$c$, its asymptotic value is constant and consistent with Au$+$Au and $p$$+$$p$ and does not show any significant dependence on collision centrality. Similar results were obtained in hadron-hadron, hadron-nucleus, and nucleus-nucleus collisions as well as in $e^+e^-$ collisions in a range of collision energies $\sqrt{s_{_{NN}}}=$3--1800 GeV. This suggests that the quark-gluon-plasma medium produced in Cu$+$Cu collisions either does not affect the jet fragmentation into light mesons or it affects the $\pi^0$ and $\eta$ the same way.

48 data tables

$\pi^0$ spectra from figure 3a from minimum bias Cu+Au collisions. Type A uncertainties are uncorrelated point-to-point. Type B uncertainties are correlated point-to-point. Type C uncertainties affect the scale of the data.

$\pi^0$ spectra from figure 3a from 0-10% central Cu+Au collisions. Type A uncertainties are uncorrelated point-to-point. Type B uncertainties are correlated point-to-point. Type C uncertainties affect the scale of the data.

$\pi^0$ spectra from figure 3a from 10-20% central Cu+Au collisions. Type A uncertainties are uncorrelated point-to-point. Type B uncertainties are correlated point-to-point. Type C uncertainties affect the scale of the data.

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Measurement of two-particle correlations with respect to second- and third-order event planes in Au$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.C 99 (2019) 054903, 2019.
Inspire Record 1658594 DOI 10.17182/hepdata.115992

We present measurements of azimuthal correlations of charged hadron pairs in $\sqrt{s_{_{NN}}}=200$ GeV Au$+$Au collisions after subtracting an underlying event using a model that includes higher-order azimuthal anisotropy $v_2$, $v_3$, and $v_4$. After subtraction, the away-side ($\Delta\phi\sim\pi)$ of the highest transverse-momentum trigger ($p_T>4$ GeV/$c$) correlations is suppressed compared to that of correlations measured in $p$$+$$p$ collisions. At the lowest associated particle $p_T$, the away-side shape and yield are modified. These observations are consistent with the scenario of radiative-jet energy loss. For the lowest-$p_T$ trigger correlations, an away-side yield exists and we explore the dependence of the shape of the away-side within the context of an underlying-event model. Correlations are also studied differentially versus event-plane angle $\Psi_n$. The angular correlations show an asymmetry when selecting the sign of the trigger-particle azimuthal angle with respect to the $\Psi_2$ event plane. This asymmetry and the measured suppression of the pair yield out of plane is consistent with a path-length-dependent energy loss. No $\Psi_3$ dependence can be resolved within experimental uncertainties.

33 data tables

Higher-order flow harmonics for charged hadrons at midrapidity in Au$+$Au collisions at $\sqrt{s_{NN}}$ and their systematics: $v_2$, $v_3$, $v_4$, and $v_4\{\Psi_2\}$. The source of systematic uncertainties are difference among RXN event-planes, matching cut width for CNT hadron tracks, and difference between $v_n$ measured with RXN and BBC event planes .

Per-trigger yields $Y(\Delta\phi)$ of dihadrons pairs measured in Au$+$Au collisions at$\sqrt{s_{NN}}$ after subtracting the underlying event model with several $p_T$ selections and centralities. Systematic uncertainties are due to track matching and the $v_n$ and due to ZYAM.

Per-trigger yields $Y(\Delta\phi)$ of dihadron pairs measured in Au$+$Au collisions after subtracting the underlying event-model with several $p_T$ selections of the trigger and associated particles ($p_T^{t,a}$ and several centralities. Systematic uncertainties are due to track matching and the $v_n$ and due to ZYAM.

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Suppression of hadrons with large transverse momentum in central 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. 88 (2002) 022301, 2002.
Inspire Record 562409 DOI 10.17182/hepdata.110700

Transverse momentum spectra for charged hadrons and for neutral pions in the range 1 GeV/c $< p_T <$ 5 GeV/c have been measured by the PHENIX experiment at RHIC in Au+Au collisions at $\sqrt{s_{_{NN}}}=130$ GeV. At high $p_T$ the spectra from peripheral nuclear collisions are consistent with the naive expectation of scaling the spectra from p+p collisions by the average number of binary nucleon- nucleon collisions. The spectra from central collisions are significantly suppressed when compared to the binary- scaled p+p expectation, and also when compared to similarly binary-scaled peripheral collisions, indicating a novel nuclear effect in central nuclear collisions at RHIC energies.

12 data tables

The yields per event at mid-rapidity for neutral pions as a function of $p_T$ for 0-80% from the PbSc detector.

The yields per event at mid-rapidity for neutral pions as a function of $p_T$ for 60-80% from the PbSc detector.

The yields per event at mid-rapidity for neutral pions as a function of $p_T$ for 0-10% from the PbGl detector.

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Double helicity asymmetry in inclusive mid-rapidity pi0 production for polarized p + p collisions at s**(1/2) = 200-GeV.

The PHENIX collaboration Adler, S.S. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.Lett. 93 (2004) 202002, 2004.
Inspire Record 648739 DOI 10.17182/hepdata.137768

We present a measurement of the double longitudinal spin asymmetry in inclusive pi^0 production in polarized proton-proton collisions at sqrt(s)=200 GeV. The data were taken at the Relativistic Heavy Ion Collider with average beam polarizations of 26%. The measurements are the first of a program to study the longitudinal spin structure of the proton, using strongly interacting probes, at collider energies. The asymmetry is presented for transverse momenta 1-5 GeV/c at mid-rapidity, where next-to-leading order perturbative quantum chromodynamic (NLO pQCD) calculations describe the unpolarized cross section well. The observed asymmetry is small and is compared with a NLO pQCD calculation with a range of polarized gluon distributions.

3 data tables

Double spin asymmetry for the raw signal ($\pi^0 + BG$), for the background ($BG$) and for $\pi^0$ background corrected; single spin asymmetry for $\pi^0$ background corrected; for the four $p_T$ bins.

Single spin raw asymmetry normalized by the beam polarization, $\epsilon$/$P$, as a function of azimuthal angle $\phi$, for forward neutron production.

The measured double spin asymmetry $A^{\pi^0}_{LL}$ versus mean $p_T$ of $\pi^0$s in each bin. Not included in the figure/table: the correlated for all points scale systematic uncertainty of 65% (scales values and stat. uncertainties of points by the same factor).


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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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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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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Bose-Einstein correlations of charged pion pairs 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.Lett. 93 (2004) 152302, 2004.
Inspire Record 642225 DOI 10.17182/hepdata.140436

Bose-Einstein correlations of identically charged pion pairs were measured by the PHENIX experiment at mid-rapidity in Au+Au collisions at $\sqrt{s_{\rm NN}}$ = 200 GeV. The Bertsch-Pratt radius parameters were determined as a function of the transverse momentum of the pair and as a function of the centrality of the collision. Using the \it{full} Coulomb correction, the ratio $R_{\rm out}/R_{\rm side}$ is smaller than unity for $<k_{\rm T}>$ from 0.25 to 1.2 GeV/c and for all measured centralities. However, using recently developed partial Coulomb correction methods, we find that $R_{\rm out}/R_{\rm side}$ is 0.8-1.1 for the measured $<k_{\rm T}>$ range, and approximately constant at unity with the number of participants.

5 data tables

Panel (a) and (b) show one-dimensional correlation functions for $\pi^+\pi^+$ and $\pi^-\pi^-$. The bottom figures show the three-dimensional correlation function for $\pi^-\pi^-$ with the full Coulomb (open circle) and without Coulomb (filled triangle) corrections for 0.2 < $k_T$ < 2.0 GeV/$c$ for 0-30% centrality. The projection of the 3-D correlation functions are averaged over the lowest 40 MeV in the orthogonal directions. The error bars are statistical only. The lines overlaid on the open circles (filled triangles) correspond to fits to Eq. 1 (Eq. 2) over the entire distribution. Panel (c) shows the one-dimensional correlation function of unlike-signed pions for 0.2 < $k_T$ < 2.0 GeV/$c$. The two overlaid histograms show calculations for the full (dashed) and the 50% partial (solid) Coulomb corrections. $<k_T>$ ~ 0.45 ($\pm$0.17) GeV/$c$ and $<N_{part}>$ ~ 281 ($\pm$4).

The $k_T$ dependence of the Bertsch-Pratt radius parameters and $\lambda$ for charged pions for 0-30% centrality. Filled triangles show the results from fits to a core-halo structure by Eq. 2, with statistical error bars and systematic error bands. Open circles and squares show the results from the full (Eq. 1) and 50% partial (Eq. 3) Coulomb corrections with statistical error bars, respectively. Results at 130 GeV by PHENIX are given by filled circles.

The $k_T$ dependence of the Bertsch-Pratt radius parameters and $\lambda$ for charged pions for 0-30% centrality. Filled triangles show the results from fits to a core-halo structure by Eq. 2, with statistical error bars and systematic error bands. Open circles and squares show the results from the full (Eq. 1) and 50% partial (Eq. 3) Coulomb corrections with statistical error bars, respectively. Results at 130 GeV by PHENIX are given by filled circles.

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