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One of the primary goals of nuclear physics is to understand the force between nucleons, which is a necessary step for understanding the structure of nuclei and how nuclei interact with each other. Rutherford discovered the atomic nucleus in 1911, and the large body of knowledge about the nuclear force since acquired was derived from studies made on nucleons or nuclei. Although antinuclei up to antihelium-4 have been discovered and their masses measured, we have no direct knowledge of the nuclear force between antinucleons. Here, we study antiproton pair correlations among data taken by the STAR experiment at the Relativistic Heavy Ion Collider and show that the force between two antiprotons is attractive. In addition, we report two key parameters that characterize the corresponding strong interaction: namely, the scattering length (f0) and effective range (d0). As direct information on the interaction between two antiprotons, one of the simplest systems of antinucleons, our result provides a fundamental ingredient for understanding the structure of more complex antinuclei and their properties.
Elliptic flow (v_2) values for identified particles at midrapidity in Au + Au collisions measured by the STAR experiment in the Beam Energy Scan at the Relativistic Heavy Ion Collider at sqrt{s_{NN}}= 7.7--62.4 GeV are presented for three centrality classes. The centrality dependence and the data at sqrt{s_{NN}}= 14.5 GeV are new. Except at the lowest beam energies we observe a similar relative v_2 baryon-meson splitting for all centrality classes which is in agreement within 15% with the number-of-constituent quark scaling. The larger v_2 for most particles relative to antiparticles, already observed for minimum bias collisions, shows a clear centrality dependence, with the largest difference for the most central collisions. Also, the results are compared with A Multiphase Transport Model and fit with a Blast Wave model.
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The difference in $v_{2}$ between particles (X) and their corresponding antiparticles $\bar{X}$ (see legend) as a function of $\sqrt{s_{NN}}$ for 10%-40% central Au + Au collisions. The systematic errors are shown by the hooked error bars. The dashed lines in the plot are fits with a power-law function.
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The difference in $v_{2}$ between protons and antiprotons as a function of $\sqrt{s_{NN}}$ for 0%-10%, 10%-40% and 40%-80% central Au + Au collisions. The systematic errors are shown by the hooked error bars. The dashed lines in the plot are fits with a power-law function.
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The relative difference. The systematic errors are shown by the hooked error bars. The dashed lines in the plot are fits with a power-law function.
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The $v_{2}$ difference between protons and antiprotons (and between $\pi^{+}$ and $pi^{-}$) for 10%-40% centrality Au+Au collisions at 7.7, 11.5, 14.5, and 19.6 GeV. The $v_{2}{BBC} results were slightly shifted horizontally.
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The angular and energy distributions of pions produced by 650-MeV protons and pion-nucleon correlations were studied using a liquid hydrogen bubble chamber. The present investigation indicates that the experimental angular distributions of neutral and charged pions are consis- tent with the assumption of isotopic spin conservation. The contributions of rrN subsystem states with isospin T 11'N = 7' 2 and % are measured; the contribution of the latter is 72 ± 3%.
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We present high precision measurements of elliptic flow near midrapidity ($|y|<1.0$) for multi-strange hadrons and $\phi$ meson as a function of centrality and transverse momentum in Au+Au collisions at center of mass energy $\sqrt{s_{NN}}=$ 200 GeV. We observe that the transverse momentum dependence of $\phi$ and $\Omega$ $v_{2}$ is similar to that of $\pi$ and $p$, respectively, which may indicate that the heavier strange quark flows as strongly as the lighter up and down quarks. This observation constitutes a clear piece of evidence for the development of partonic collectivity in heavy-ion collisions at the top RHIC energy. Number of constituent quark scaling is found to hold within statistical uncertainty for both 0-30$\%$ and 30-80$\%$ collision centrality. There is an indication of the breakdown of previously observed mass ordering between $\phi$ and proton $v_{2}$ at low transverse momentum in the 0-30$\%$ centrality range, possibly indicating late hadronic interactions affecting the proton $v_{2}$.
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We present measurements of $\Omega$ and $\phi$ production at mid-rapidity from Au+Au collisions at nucleon-nucleon center-of-mass energies $\sqrt{s_{NN}}$ = 7.7, 11.5, 19.6, 27 and 39 GeV by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). Motivated by the coalescence formation mechanism for these strange hadrons, we study the ratios of $N(\Omega^{-}+\Omega^{+})/(2N(\phi))$. These ratios as a function of transverse momentum ($p_T$) fall on a consistent trend at high collision energies, but start to show deviations in peripheral collisions at $\sqrt{s_{NN}}$ = 19.6, 27 and 39 GeV, and in central collisions at 11.5 GeV in the intermediate $p_T$ region of 2.4-3.6 GeV/c. We further evaluate empirically the strange quark $p_T$ distributions at hadronization by studying the $\Omega/\phi$ ratios scaled by the number of constituent quarks. The NCQ-scaled $\Omega/\phi$ ratios show a suppression of strange quark production in central collisions at 11.5 GeV compared to $\sqrt{s_{NN}} >= 19.6$ 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.
Phi Meson Spectra.
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ks(pTs) = N(Omega+Anti-Omega)_(pT=3pTs)/2N(phi)_(pT=2pTs) N is the invariant yield.
ks(pTs) = N(Omega+Anti-Omega)_(pT=3pTs)/2N(phi)_(pT=2pTs) N is the invariant yield.
ks(pTs) = N(Omega+Anti-Omega)_(pT=3pTs)/2N(phi)_(pT=2pTs) N is the invariant yield.
ks(pTs) = N(Omega+Anti-Omega)_(pT=3pTs)/2N(phi)_(pT=2pTs) N is the invariant yield.
ks(pTs) = N(Omega+Anti-Omega)_(pT=3pTs)/2N(phi)_(pT=2pTs) N is the invariant yield.
ks(pTs) = N(Omega+Anti-Omega)_(pT=3pTs)/2N(phi)_(pT=2pTs) N is the invariant yield.
Collisions between prolate uranium nuclei are used to study how particle production and azimuthal anisotropies depend on initial geometry in heavy-ion collisions. We report the two- and four-particle cumulants, $v_2\{2\}$ and $v_2\{4\}$, for charged hadrons from U+U collisions at $\sqrt{s_{\rm NN}}$ = 193 GeV and Au+Au collisions at $\sqrt{s_{\rm NN}}$ = 200 GeV. Nearly fully overlapping collisions are selected based on the amount of energy deposited by spectators in the STAR Zero Degree Calorimeters (ZDCs). Within this sample, the observed dependence of $v_2\{2\}$ on multiplicity demonstrates that ZDC information combined with multiplicity can preferentially select different overlap configurations in U+U collisions. An initial-state model with gluon saturation describes the slope of $v_2\{2\}$ as a function of multiplicity in central collisions better than one based on Glauber with a two-component multiplicity model.
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We present measurements of $\pi^-$ and $\pi^+$ elliptic flow, $v_2$, at midrapidity in Au+Au collisions at $\sqrt{s_{_{\rm NN}}} =$ 200, 62.4, 39, 27, 19.6, 11.5 and 7.7 GeV, as a function of event-by-event charge asymmetry, $A_{ch}$, based on data from the STAR experiment at RHIC. We find that $\pi^-$ ($\pi^+$) elliptic flow linearly increases (decreases) with charge asymmetry for most centrality bins at $\sqrt{s_{_{\rm NN}}} = \text{27 GeV}$ and higher. At $\sqrt{s_{_{\rm NN}}} = \text{200 GeV}$, the slope of the difference of $v_2$ between $\pi^-$ and $\pi^+$ as a function of $A_{ch}$ exhibits a centrality dependence, which is qualitatively similar to calculations that incorporate a chiral magnetic wave effect. Similar centrality dependence is also observed at lower energies.
The distribution of observed charge asymmetry from STAR data.
Pion $v_2${2} as a function of observed charge asymmetry.
$v_2$ difference between $\pi^-$ and $\pi^+$ as a function of charge asymmetry with the tracking efficiency correction, for 30-40% central Au+Au collisions at 200 GeV. The errors are statistical only.
The slope parameter r as a function of centrality for collision energy of 200 GeV.
The slope parameter r as a function of centrality for collision energy of 62.4 GeV.
The slope parameter r as a function of centrality for collision energy of 39 GeV.
The slope parameter r as a function of centrality for collision energy of 27 GeV.
The slope parameter r as a function of centrality for collision energy of 19.6 GeV.
The slope parameter r as a function of centrality for collision energy of 11.5 GeV.
The slope parameter r as a function of centrality for collision energy of 7.7 GeV.
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 RHIC. Systematic measurements of the dielectron yield as a function of transverse momentum ($p_{\rm T}$) and collision centrality show an enhancement compared to a cocktail simulation of hadronic sources in the low invariant-mass region ($M_{ee}<$ 1 GeV/$c^2$). This enhancement cannot be reproduced by the $\rho$-meson vacuum spectral function. In minimum-bias collisions, in the invariant-mass range of 0.30 $-$ 0.76 GeV/$c^2$, integrated over the full $p_{\rm T}$ acceptance, the enhancement factor is 1.76 $\pm$ 0.06 (stat.) $\pm$ 0.26 (sys.) $\pm$ 0.29 (cocktail). The enhancement factor exhibits weak centrality and $p_{\rm T}$ 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 $\pm$ 0.10. Models that assume an in-medium broadening of the $\rho$ meson spectral function consistently describe the observed excess in these measurements. Additionally, we report on measurements of $\omega$ and $\phi$-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 $\phi$-meson, results through its $K^+K^-$ decay channel. In the intermediate invariant-mass region (1.1$<M_{ee}<$ 3 GeV/$c^2$), 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.
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.
$e^+$ $e^-$ invariant mass pair distributions of signal pairs compared to the inclusive unlike sign and reconstructed background pairs in 200 GeV Au+Au minimum-bias collisions.
Signal-to-background ratios in minimum bias p+p and Au+Au collisions.
Signal-to-background ratios in central p+p and Au+Au collisions.
Invariant mass spectrum in the STAR acceptance ($p_T^e$ > 0.2 GeV/c, |$\eta^e$| < 1, and |$y_{ee}$|) from SQRT($s_{NN}$) = 200 GeV Au+Au minimum-bias collisions.
Invariant mass spectrum in the STAR acceptance ($p_T^e$ > 0.2 GeV/c, |$\eta^e$| < 1, and |$y_{ee}$|) from SQRT($s_{NN}$) = 200 GeV Au+Au minimum-bias collisions.
Invariant mass spectra from SQRT($s_{NN}$ = 200 GeV Au+Au minimum-bias collisions in pT range 0 - 5 GeV/c. The ratio of dielectron yield over cocktail for different pT bins, and the comparison with model calculations.
Invariant mass spectra from SQRT($s_{NN}$ = 200 GeV Au+Au minimum-bias collisions in pT range 5 - 10 GeV/c. The ratio of dielectron yield over cocktail for different pT bins, and the comparison with model calculations.
Invariant mass spectra from SQRT($s_{NN}$ = 200 GeV Au+Au minimum-bias collisions in pT range 1 - 1.5 GeV/c. The ratio of dielectron yield over cocktail for different pT bins, and the comparison with model calculations.
Invariant mass spectra from SQRT($s_{NN}$ = 200 GeV Au+Au minimum-bias collisions in pT range 1.5 - 2 GeV/c. The ratio of dielectron yield over cocktail for different pT bins, and the comparison with model calculations.
Invariant mass spectra from SQRT($s_{NN}$ = 200 GeV Au+Au minimum-bias collisions integrated. The ratio of dielectron yield over cocktail for different pT bins, and the comparison with model calculations.
The integrated dielectron yield as a function of pair pT in invariant mass range 0 - 0.15 GeV/c^2 compared with cocktail. The ratio of dielectron yield over cocktail for different mass ranges as a function of pair pT.
The integrated dielectron yield as a function of pair pT in invariant mass range 0.15 - 0.3 GeV/c^2 compared with cocktail. The ratio of dielectron yield over cocktail for different mass ranges as a function of pair pT.
The integrated dielectron yield as a function of pair pT in invariant mass range 0.3 - 0.76 GeV/c^2 compared with cocktail. The ratio of dielectron yield over cocktail for different mass ranges as a function of pair pT.
The integrated dielectron yield as a function of pair pT in invariant mass range 0.76 - 1.05 GeV/c^2 compared with cocktail. The ratio of dielectron yield over cocktail for different mass ranges as a function of pair pT.
The integrated dielectron yield as a function of pair pT in invariant mass range 1.05 - 1.8 GeV/c^2 compared with cocktail. The ratio of dielectron yield over cocktail for different mass ranges as a function of pair pT.
The integrated dielectron yield as a function of pair pT in invariant mass range 1.8 - 2.8 GeV/c^2 compared with cocktail. The ratio of dielectron yield over cocktail for different mass ranges as a function of pair pT.
The integrated dielectron yield as a function of pair pT in invariant mass range 2.8 to 3.5 GeV/c^2 compared with cocktail. The ratio of dielectron yield over cocktail for different mass ranges as a function of pair pT.
Invariant mass spectra from SQRT($s_{NN}$) = 200 GeV Au+Au collisions in different centralities. The ratio of dielectron yield over cocktail for a centrality of 0-10%.
Invariant mass spectra from SQRT($s_{NN}$) = 200 GeV Au+Au collisions in different centralities. The ratio of dielectron yield over cocktail for a centrality of 10-40%.
Invariant mass spectra from SQRT($s_{NN}$) = 200 GeV Au+Au collisions in different centralities. The ratio of dielectron yield over cocktail for a centrality of 40-80%.
Invariant mass spectra from SQRT($s_{NN}$) = 200 GeV Au+Au collisions in different centralities. The ratio of dielectron yield over cocktail for minimum bias.
The integrated dielectron yield and ratio of dielectron yield over cocktail in different centralities for mass window 0 - 0.15 GeV/c^2, and the comparison with model calculations.
The integrated dielectron yield and ratio of dielectron yield over cocktail in different centralities for mass window 0.15 - 0.3 GeV/c^2, and the comparison with model calculations.
The integrated dielectron yield and ratio of dielectron yield over cocktail in different centralities for mass window 0.3 - 0.76 GeV/c^2, and the comparison with model calculations.
The integrated dielectron yield and ratio of dielectron yield over cocktail in different centralities for mass window 0.76 - 1.05 GeV/c^2, and the comparison with model calculations.
The integrated dielectron yield and ratio of dielectron yield over cocktail in different centralities for mass window 1.05 - 1.8 GeV/c^2, and the comparison with model calculations.
The integrated dielectron yield and ratio of dielectron yield over cocktail in different centralities for mass window 1.8 - 2.8 GeV/c^2, and the comparison with model calculations.
The integrated dielectron yield and ratio of dielectron yield over cocktail in different centralities for mass window 2.8 - 3.5 GeV/c^2, and the comparison with model calculations.
Dielectron invariant mass spectra from minimum-bias.
Dielectron invariant mass spectra from the most central (0-10%) collisions that we are able to achieve most statistics at present.
The ratio of the Npart-scaled dielectron yield between minimum-bias and the most central collisions.
Mass spectrum of the excess (data - cocktail) in the low-mass region in Au+Au minimum-bias collisions compared to model calculations.
The yields scaled by Npart for the $\rho$-like region with the cocktail subtracted.
The Omega-like region without cocktail subtraction as a function of Npart.
The Phi-like region without cocktail subtraction as a function of Npart.
Correlated charm contributions to the dielectron mass spectra for different assumptions of the correlation strength.
Slope parameters Teff versus invariant mass for dielectrons from charm hadron decays.
Omega meson invariant mass distribution from SQRT($s_{NN}$) = 200 GeV Au+Au minimum-bias collisions after subtraction of the combinatorial background using the mixed-event method.
Phi meson invariant mass distribution from SQRT($s_{NN}$) = 200 GeV Au+Au minimum-bias collisions after subtraction of the combinatorial background using the mixed-event method.
The widths and mass positions of the omega signal from data compared to the values from the PDG and the full Geant simulation.
The widths and mass positions of the phi signal from data compared to the values from the PDG and the full Geant simulation.
The efficiency and acceptance correction factor as function of pT for mid-rapidity omega and phi mesons.
The pT distributions of the omega meson invariant yields from SQRT($s_{NN}$) = 200 GeV Au+Au minimum-bias collisions.
The pT distributions of the phi meson invariant yields from SQRT($s_{NN}$) = 200 GeV Au+Au minimum-bias collisions.
Unlike-sign/like-sign pair acceptance difference correction factor with the PHENIX phi acceptance compared with the full acceptance.
Efficiency corrected invariant mass spectra calculated using the STAR data filtered with the PHENIX azimuthal angle acceptance. The data points are compared to cocktail simulations.
The same data points compared to theoretical model calculations of medium vector meson and QGP contributions.
We report the observation of transverse polarization-dependent azimuthal correlations in charged pion pair production with the STAR experiment in $p^\uparrow+p$ collisions at RHIC. These correlations directly probe quark transversity distributions. We measure signals in excess of five standard deviations at high transverse momenta, at high pseudorapidities eta>0.5, and for pair masses around the mass of the rho-meson. This is the first direct transversity measurement in p+p collisions. Comparing the results to data from lepton-nucleon scattering will test the universality of these spin-dependent quantities.
$p_T$ asymmetries, $\eta$ < 0, maximum opening angle of 0.2.
$<M_{inv}>$ asymmetries, $\eta$ < 0, maximum opening angle of 0.2.
$p_T$ asymmetries, $\eta$ > 0, maximum opening angle 0.2.
$<M_{inv}>$ asymmetries, $\eta$ > 0, maximum opening angle 0.2.
$p_T$ asymmetries, $\eta$ < 0, maximum opening angle 0.3.
$<M_{inv}>$ asymmetries, $\eta$ < 0, maximum opening angle 0.3.
$p_T$ asymmetries, $\eta$ > 0,maximum opening angle 0.3.
$<M_{inv}>$ asymmetries, $\eta$ > 0, maximum opening angle 0.3.
$p_T$ asymmetries, $\eta$ < 0, maximum opening angle 0.4.
$<M_{inv}>$ asymmetries, $\eta$ < 0, maximum opening angle 0.4.
$p_T$ asymmetries, $\eta$ > 0, maximum opening angle 0.4.
$<M_{inv}>$ asymmetries, $\eta$ > 0, maximum opening angle 0.4.
$\eta$ asymmetries, maximum opening angle 0.2.
$\eta$ asymmetries, maximum opening angle 0.3.
$\eta$ asymmetries, maximum opening angle 0.4.
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.
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.
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 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 2 < $\Delta\eta$ < 4.5 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 2 < $\Delta\eta$ < 4.5 in d+Au collisions, for high ZDC-Au activity data. Both the trigger and associated particles have 1 < $p_T$ < 3 GeV/c.
The $\Delta\eta$ dependence of the near-side (|$\Delta\phi$| < $\pi/3$) correlated yield. Positive(negative) $\eta$ corresponds to d(Au)-going direction. Only high ZDC-Au activity data are shown.
The $\Delta\eta$ dependence of the away-side (|$\Delta\phi - \pi$| < $\pi/3$) correlated yield. Positive(negative) $\eta$ corresponds to d(Au)-going direction. Only high ZDC-Au activity data are shown.
The $\Delta\eta$ dependence of the ratio of the near- to away-side correlated yields in d+Au collisions. Positive(negative) $\eta$ corresponds to d(Au)-going direction. Only high ZDC-Au activity data are shown.
The $\Delta\eta$ dependence of the second harmonic Fourier coefficient, V2, in low ZDC-Au activity d+Au collisions.
The $\Delta\eta$ dependence of the second harmonic Fourier coefficient, V2, in high ZDC-Au activity d+Au collisions.
Fourier coefficient V1 versus the measured mid-rapidity charged particle $dN_{ch}/d\eta$. Event activity selection is by FTPC-Au. Trigger particles are from TPC, and associated particles from TPC. Systematic uncertainties are estimated to be 10% on V1. Errors shown are the quadratic sum of statistical and systematic errors.
Fourier coefficient V1 versus the measured mid-rapidity charged particle $dN_{ch}/d\eta$. Event activity selection is by ZDC. Trigger particles are from TPC, and associated particles from FTPC-Au. Systematic uncertainties are estimated to be 10% on V1. Errors shown are the quadratic sum of statistical and systematic errors.
Fourier coefficient V1 versus the measured mid-rapidity charged particle $dN_{ch}/d\eta$. Event activity selection is by ZDC. Trigger particles are from TPC, and associated particles from FTPC-d. Systematic uncertainties are estimated to be 10% on V1. Errors shown are the quadratic sum of statistical and systematic errors.
Fourier coefficient V1 versus the measured mid-rapidity charged particle $dN_{ch}/d\eta$. Event activity selection is by ZDC-Au. Trigger particles are from TPC, and associated particles from TPC. Systematic uncertainties are estimated to be 10% on V1. Errors shown are the quadratic sum of statistical and systematic errors.
Fourier coefficient V2 versus the measured mid-rapidity charged particle $dN_{ch}/d\eta$. Event activity selection is by FTPC-Au. Trigger particles are from TPC, and associated particles from TPC. Systematic uncertainties are estimated to be 10% on V2. Errors shown are the quadratic sum of statistical and systematic errors.
Fourier coefficient V2 versus the measured mid-rapidity charged particle $dN_{ch}/d\eta$. Event activity selection is by ZDC-Au. Trigger particles are from TPC, and associated particles from FTPC-Au. Systematic uncertainties are estimated to be 10% on V2. Errors shown are the quadratic sum of statistical and systematic errors.
Fourier coefficient V2 versus the measured mid-rapidity charged particle $dN_{ch}/d\eta$. Event activity selection is by ZDC-Au. Trigger particles are from TPC, and associated particles from FTPC-d. Systematic uncertainties are estimated to be 10% on V2. Errors shown are the quadratic sum of statistical and systematic errors.
Fourier coefficient V2 versus the measured mid-rapidity charged particle $dN_{ch}/d\eta$. Event activity selection is by ZDC-Au. Trigger particles are from TPC, and associated particles from TPC. Systematic uncertainties are estimated to be 10% on V2. Errors shown are the quadratic sum of statistical and systematic errors.
Fourier coefficient V3 versus the measured mid-rapidity charged particle $dN_{ch}/d\eta$. Event activity selections is by FTPC-Au. Trigger particles are from TPC, and associated particles from TPC. Systematic uncertainties are estimated to be smaller than statistical errors for V3. Errors shown are the quadratic sum of statistical and systematic errors.
Fourier coefficient V3 versus the measured mid-rapidity charged particle $dN_{ch}/d\eta$. Event activity selection is by ZDC-Au. Trigger particles are from TPC, and associated particles from FTPC-Au. Systematic uncertainties are estimated to be smaller than statistical errors for V3. Errors shown are the quadratic sum of statistical and systematic errors.
Fourier coefficient V3 versus the measured mid-rapidity charged particle $dN_{ch}/d\eta$. Event activity selection is by ZDC-Au. Trigger particles are from TPC, and associated particles from FTPC-d. Systematic uncertainties are estimated to be smaller than statistical errors for V3. Errors shown are the quadratic sum of statistical and systematic errors.
Fourier coefficient V3 versus the measured mid-rapidity charged particle $dN_{ch}/d\eta$. Event activity selection is by ZDC-Au. Trigger particles are from TPC, and associated particles from TPC. Systematic uncertainties are estimated to be smaller than statistical errors for V3. Errors shown are the quadratic sum of statistical and systematic errors.
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