Measurements of two-particle correlations in $e^+e^-$ collisions at 91 GeV with ALEPH archived data

Badea, Anthony ; Baty, Austin ; Chang, Paoti ; et al.
Phys.Rev.Lett. 123 (2019) 212002, 2019.
Inspire Record 1737859 DOI 10.17182/hepdata.99975

Measurements of two-particle angular correlations of charged particles emitted in hadronic $Z$ decays are presented. The archived $e^+e^-$ annihilation data at a center-of-mass energy of 91 GeV were collected with the ALEPH detector at LEP between 1992 and 1995. The correlation functions are measured over a broad range of pseudorapidity and full azimuth as a function of charged particle multiplicity. No significant long-range correlation is observed in either the lab coordinate analysis or the thrust coordinate analysis, where the latter is sensitive to a medium expanding transverse to the color string between the outgoing $q\bar{q}$ pair from $Z$ boson decays. The associated yield distributions in both analyses are in better agreement with the prediction from the PYTHIA v6.1 event generator than from HERWIG v7.1.5. They provide new insights to showering and hadronization modeling. These results serve as an important reference to the observed long-range correlation in proton-proton, proton-nucleus, and nucleus-nucleus collisions.

4 data tables

Correlated yield obtained from the ZYAM procedure as a function of |Deltaphi| averaged over 1.6 < |Deltaeta| < 3.2 in lab coordinate analyses.

Correlated yield obtained from the ZYAM procedure as a function of $|\Delta\phi |$ averaged over $1.6 < |\Delta\eta| < 3.2$ in thrust coordinate analyses.

Confidence limits on associated yield with lab coordinates as a function of avg N_trk^corr. NOTE in the PRL paper figure the lab data has been shifted right three units for clarity, but in this table the points are NOT shifted.

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Measurements of phi meson production in relativistic heavy-ion collisions at RHIC

The STAR collaboration Abelev, B.I. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.C 79 (2009) 064903, 2009.
Inspire Record 797805 DOI 10.17182/hepdata.99047

We present results for the measurement of $\phi$ meson production via its charged kaon decay channel $\phi \to K^+K^-$ in Au+Au collisions at $\sqrt{s_{_{NN}}}=62.4$, 130, 200 GeV, and in p+p and d+Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV from the STAR experiment at RHIC. The mid-rapidity ($|y|<0.5$) $\phi$ meson spectra in central Au+Au collisions are found to be well described by a single exponential distribution. On the other hand, the spectra from p+p, d+Au and peripheral Au+Au collisions show power-law tails at intermediate and high transverse momenta ($p_{T}$) and are described better by Levy distributions. The constant $\phi/K^-$ yield ratio vs. beam species, collision centrality and colliding energy is in contradiction with expectations from models having kaon coalescence as the dominant mechanism for $\phi$ production at RHIC. The $\Omega/\phi$ yield ratio as a function of $p_{T}$ is consistent with a model based on the recombination of thermal $s$ quarks up to $p_{T}\sim 4$ GeV/c, but disagrees at higher transverse momenta. The measured nuclear modification factor, $R_{dAu}$, for the $\phi$ meson increases above unity at intermediate $p_{T}$, similar to that for pions and protons, while $R_{AA}$ is suppressed due to jet quenching in central Au+Au collisions. Number of constituent quark scaling of both $R_{cp}$ and $v_{2}$ for the $\phi$ meson with respect to other hadrons in Au+Au collisions at $\sqrt{s_{_{NN}}}$=200 GeV at intermediate $p_{T}$ is observed. These observations support quark coalescence as being the dominant mechanism of hadronization in the intermediate $p_{T}$ region at RHIC.

81 data tables

Background-subtracted invariant mass distributions at 0.4 < $p_{T}$ < 0.8 GeV/c in d + Au 200 GeV collisions (0–100%) with (solid points) and without (open points) the $\delta$-dipangle cut. The dashed curves show a Breit-Wigner (see the text for details) + linear background function fit to the case with the $\delta$-dip-angle cut.

Background-subtracted invariant mass distributions at 0.4 < $p_{T}$ < 0.8 GeV/c in d + Au 200 GeV collisions (0–100%) with (solid points) and without (open points) the $\delta$-dipangle cut. The dashed curves show a Breit-Wigner (see the text for details) + linear background function fit to the case with the $\delta$-dip-angle cut.

Upper panels: same-event (full points) and mixed-event (solid line) $K^{+}K^{-}$ invariant mass distributions at 0.6 < $p_{T}$ < 1.4 GeV/c in p + p 200 GeV collisions (a), 0.8 < $p_{T}$ < 1.2 GeV/c in Au + Au 62.4 GeV collisions (60–80%) (c), and 0.8 < $p_{T}$ < 1.2 GeV/c in Au + Au 200 GeV collisions (0–10%) (e). Lower panels: the corresponding $\phi$ meson mass peaks after subtracting the background. Dashed curves show a Breit-Wigner + linear background function fit in (b), (d). In (f), both linear and quadratic backgrounds are shown as dashed and dot-dashed lines, respectively.

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Multiplicity and pseudorapidity distributions of photons in Au + Au collisions at s(NN)**(1/2) = 62.4-GeV

The STAR collaboration Adams, J. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.Lett. 95 (2005) 062301, 2005.
Inspire Record 676188 DOI 10.17182/hepdata.98929

We present the first measurement of multiplicity and pseudorapidity distributions of photons in the pseudorapidity region 2.3 $\le$ $\eta$ $\le$ 3.7 for different centralities in Au + Au collisions at $\sqrt{s_{NN}}$ = 62.4 GeV. We find that the photon yield in this pseudorapidity range scales with the number of participating nucleons at all collision centralities studied. The pseudorapidity distribution of photons, dominated by neutral pion decays, has been compared to those of identified charged pions, photons, and inclusive charged particles from heavy ion and nucleon-nucleon collisions at various energies. The photon production in the measured pseudorapidity region has been shown to be consistent with the energy and centrality independent limiting fragmentation scenario.

3 data tables

${dN_{\gamma}}\over{d\eta}$ for various event centrality classes compared to HIJING and AMPT model calculations.

Variation of $N_{\gamma}$ per participant pair in PMD coverage $(2.3 \leq \eta \leq 3.7)$ as a function of $N_{part}$. The lower band reflects uncertainties in $N_{part}$ calculations.

(Color Online) Estimated ${dN_{\pi^{0}}}\over{dy}$ from ${dN_{\gamma}}\over{dy}$ normalized to $N_{part}$, as compared to ${dN_{\pi^{\pm}}}\over{dy}$ normalized to $N_{part}$, as a function of $y-y_{beam}$ for central collisions at various collision energies.


Scaling Properties of Hyperon Production in Au+Au Collisions at s**(1/2) = 200-GeV

The STAR collaboration Adams, J. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.Lett. 98 (2007) 062301, 2007.
Inspire Record 718755 DOI 10.17182/hepdata.98928

We present the scaling properties of Lambda, Xi, Omega and their anti-particles produced at mid-rapidity in Au+Au collisions at RHIC at sqrt(s_NN) = 200 GeV. The yield of multi-strange baryons per participant nucleon increases from peripheral to central collisions more rapidly than the Lambda yield, which appears to correspond to an increasing strange quark density of matter produced. The value of the strange phase space occupancy factor gamma_s, obtained from a thermal model fit to the data, approaches unity for the most central collisions. We also show that the nuclear modification factors, R_CP, of Lambda and Xi are consistent with each other and with that of protons in the transverse momentum range 2.0 < p_T < 5.0 GeV/c. This scaling behaviour is consistent with a scenario of hadron formation from constituent quark degrees of freedom through quark recombination or coalescence.

6 data tables

Transverse momentum distributions of (a) $\Lambda(\overline{\Lambda})$ for $|y|<1.0$, (b) $\Xi^{-}(\overline{\Xi}^{+})$ for $|y|<0.75$ and (c) $\Omega^{-}+\overline{\Omega}^{+}$ for $|y|<0.75$ in Au+Au collisions at $\sqrt{s_{NN}}$ as a function of centrality. The $\Lambda$ spectra were corrected for weak decay of $\Xi$, $\Xi^{0}$ and $\Omega$. Scale factors were applied to the spectra for clarity. Only statistical errors are shown. The dashed curves show a Boltzmann fit to the $\Lambda$, $\Xi^{-}$ and $\Omega^{-}+\overline{\Omega}^{+}$ data, the fits to the $\overline{\Lambda}$ and $\overline{\Xi}^{+}$ are omitted for clarity.

Transverse momentum distributions of (a) $\Lambda(\overline{\Lambda})$ for $|y|<1.0$, (b) $\Xi^{-}(\overline{\Xi}^{+})$ for $|y|<0.75$ and (c) $\Omega^{-}+\overline{\Omega}^{+}$ for $|y|<0.75$ in Au+Au collisions at $\sqrt{s_{NN}}$ as a function of centrality. The $\Lambda$ spectra were corrected for weak decay of $\Xi$, $\Xi^{0}$ and $\Omega$. Scale factors were applied to the spectra for clarity. Only statistical errors are shown. The dashed curves show a Boltzmann fit to the $\Lambda$, $\Xi^{-}$ and $\Omega^{-}+\overline{\Omega}^{+}$ data, the fits to the $\overline{\Lambda}$ and $\overline{\Xi}^{+}$ are omitted for clarity.

Transverse momentum distributions of (a) $\Lambda(\overline{\Lambda})$ for $|y|<1.0$, (b) $\Xi^{-}(\overline{\Xi}^{+})$ for $|y|<0.75$ and (c) $\Omega^{-}+\overline{\Omega}^{+}$ for $|y|<0.75$ in Au+Au collisions at $\sqrt{s_{NN}}$ as a function of centrality. The $\Lambda$ spectra were corrected for weak decay of $\Xi$, $\Xi^{0}$ and $\Omega$. Scale factors were applied to the spectra for clarity. Only statistical errors are shown. The dashed curves show a Boltzmann fit to the $\Lambda$, $\Xi^{-}$ and $\Omega^{-}+\overline{\Omega}^{+}$ data, the fits to the $\overline{\Lambda}$ and $\overline{\Xi}^{+}$ are omitted for clarity.

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Multiplicity and pseudorapidity distributions of charged particles and photons at forward pseudorapidity in Au + Au collisions at s(NN)**(1/2) = 62.4-GeV

The STAR collaboration Adams, J. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.C 73 (2006) 034906, 2006.
Inspire Record 697905 DOI 10.17182/hepdata.98930

We present the centrality dependent measurement of multiplicity and pseudorapidity distributions of charged particles and photons in Au + Au collisions at sqrt{s_NN} = 62.4 GeV. The charged particles and photons are measured in the pseudorapidity region 2.9 < eta < 3.9 and 2.3 < eta < 3.7, respectively. We have studied the scaling of particle production with the number of participating nucleons and the number of binary collisions. The photon and charged particle production in the measured pseudorapidity range has been shown to be consistent with energy independent limiting fragmentation behavior. The photons are observed to follow a centrality independent limiting fragmentation behavior while for the charged particles it is centrality dependent. We have carried out a comparative study of the pseudorapidity distributions of positively charged hadrons, negatively charged hadrons, photons, pions, net protons in nucleus--nucleus collisions and pseudorapidity distributions from p+p collisions. From these comparisons we conclude that baryons in the inclusive charged particle distribution are responsible for the observed centrality dependence of limiting fragmentation. The mesons are found to follow an energy independent behavior of limiting fragmentation while the behavior of baryons seems to be energy dependent.

11 data tables

(Color Online) Variation of $N_{ch}$ normalized to the number of participating nucleon pair in the FTPC coverage $(2.9 \leq \eta \leq 3.9)$ and $N_{\gamma}$ normalized to the number of participating nucleon pair in the PMD acceptance $(2.3 \leq \eta \leq 3.7)$ as a function of $N_{part}$. The lower band shows the uncertainty in the ratio due to uncertainties in $N_{part}$ calculations.

(Color Online) Variation of $N_{ch}$ normalized to the number of participating nucleon pair in the FTPC coverage $(2.9 \leq \eta \leq 3.9)$ and $N_{\gamma}$ normalized to the number of participating nucleon pair in the PMD acceptance $(2.3 \leq \eta \leq 3.7)$ as a function of $N_{part}$. The lower band shows the uncertainty in the ratio due to uncertainties in $N_{part}$ calculations.

(Color Online) Variation of $N_{ch}$ normalized to the number of collisions in the FTPC coverage $(2.9 \leq \eta \leq 3.9)$ and $N_{\gamma}$ normalized to number of collisions, in the PMD coverage $(2.3 \leq \eta \leq 3.7)$ as a function of $N_{coll}$. The lower band shows the uncertainty in the ratio due to uncertainties in $N_{coll}$ calculations.

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Pion Interferometry in Au+Au and Cu+Cu Collisions at RHIC

The STAR collaboration Abelev, B.I. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.C 80 (2009) 024905, 2009.
Inspire Record 814937 DOI 10.17182/hepdata.97124

We present a systematic analysis of two-pion interferometry in Au+Au collisions at $\sqrt{s_{\rm{NN}}}$ = 62.4 GeV and Cu+Cu collisions at $\sqrt{s_{\rm{NN}}}$ = 62.4 and 200 GeV using the STAR detector at RHIC. The multiplicity and transverse momentum dependences of the extracted femtoscopic radii are studied. The scaling of the apparent freeze-out volume with charged particle multiplicity is studied for the RHIC energy domain. The multiplicity scaling of the measured radii is found to be independent of colliding system and collision energy.

12 data tables

HBT parameters for all centralities of 62.4 GeV Au+Au

HBT parameters for 200 and 62.4 GeV Au+Au, 0-5%

Energy dependence of the pi- HBT parameters for central Au+Au, Pb+Pb, and Pb+Au collisions (AGS,SPS and RHIC) at midrapidity and k_T ~ 0.2-0.3 GeV/c.

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Collision Energy Dependence of Moments of Net-Kaon Multiplicity Distributions at RHIC

The STAR collaboration Adamczyk, L. ; Adams, J.R. ; Adkins, J.K. ; et al.
Phys.Lett.B 785 (2018) 551-560, 2018.
Inspire Record 1621460 DOI 10.17182/hepdata.98573

Fluctuations of conserved quantities such as baryon number, charge, and strangeness are sensitive to the correlation length of the hot and dense matter created in relativistic heavy-ion collisions and can be used to search for the QCD critical point. We report the first measurements of the moments of net-kaon multiplicity distributions in Au+Au collisions at $\sqrt{s_{\rm NN}}$ = 7.7, 11.5, 14.5, 19.6, 27, 39, 62.4, and 200 GeV. The collision centrality and energy dependence of the mean ($M$), variance ($\sigma^2$), skewness ($S$), and kurtosis ($\kappa$) for net-kaon multiplicity distributions as well as the ratio $\sigma^2/M$ and the products $S\sigma$ and $\kappa\sigma^2$ are presented. Comparisons are made with Poisson and negative binomial baseline calculations as well as with UrQMD, a transport model (UrQMD) that does not include effects from the QCD critical point. Within current uncertainties, the net-kaon cumulant ratios appear to be monotonic as a function of collision energy.

43 data tables

Raw $\Delta N_k$ distributions in Au+Au collisions at 7.7 GeV for 0–5%, 30–40%, and 70–80% collision centralities at midrapidity. The distributions are not corrected for the finite centrality bin width effect nor the reconstruction efficiency.

Raw $\Delta N_k$ distributions in Au+Au collisions at 11.5 GeV for 0–5%, 30–40%, and 70–80% collision centralities at midrapidity. The distributions are not corrected for the finite centrality bin width effect nor the reconstruction efficiency.

Raw $\Delta N_k$ distributions in Au+Au collisions at 14.5 GeV for 0–5%, 30–40%, and 70–80% collision centralities at midrapidity. The distributions are not corrected for the finite centrality bin width effect nor the reconstruction efficiency.

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Observation of charge-dependent azimuthal correlations and possible local strong parity violation in heavy ion collisions

The STAR collaboration Abelev, B.I. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.C 81 (2010) 054908, 2010.
Inspire Record 830676 DOI 10.17182/hepdata.98577

Parity-odd domains, corresponding to non-trivial topological solutions of the QCD vacuum, might be created during relativistic heavy-ion collisions. These domains are predicted to lead to charge separation of quarks along the orbital momentum of the system created in non-central collisions. To study this effect, we investigate a three particle mixed harmonics azimuthal correlator which is a \P-even observable, but directly sensitive to the charge separation effect. We report measurements of this observable using the STAR detector in Au+Au and Cu+Cu collisions at $\sqrt{s_{NN}}$=200 and 62~GeV. The results are presented as a function of collision centrality, particle separation in rapidity, and particle transverse momentum. A signal consistent with several of the theoretical expectations is detected in all four data sets. We compare our results to the predictions of existing event generators, and discuss in detail possible contributions from other effects that are not related to parity violation.

19 data tables

$\langle cos(\phi_{\alpha}+\phi_{\beta}−2\phi_{c})\rangle$ as a function of reference multiplicity for different charge combinations, before corrections for acceptance effects. In the legend the signs indicate the charge of particles $\alpha$, $\beta$, and c. The results shown are for Au+Au collisions at 200 GeV obtained in the Reversed Full Field.

$\langle cos(\phi_{\alpha}+\phi_{\beta}−2\phi_{c})\rangle$ as a function of reference multiplicity for different charge combinations, before corrections for acceptance effects. In the legend the signs indicate the charge of particles $\alpha$, $\beta$, and c. The results shown are for Au+Au collisions at 200 GeV obtained in the Full Field.

$\langle cos(\phi_{\alpha}+\phi_{\beta}−2\phi_{c})\rangle$ as a function of reference multiplicity for different charge combinations, after corrections for acceptance effects. In the legend the signs indicate the charge of particles $\alpha$, $\beta$, and c. The results shown are for Au+Au collisions at 200 GeV obtained in the Reversed Full Field.

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Global polarization measurement in Au+Au collisions

The STAR collaboration Abelev, B.I. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.C 76 (2007) 024915, 2007.
Inspire Record 750410 DOI 10.17182/hepdata.98581

The system created in non-central relativistic nucleus-nucleus collisions possesses large orbital angular momentum. Due to spin-orbit coupling, particles produced in such a system could become globally polarized along the direction of the system angular momentum. We present the results of Lambda and anti-Lambda hyperon global polarization measurements in Au+Au collisions at sqrt{s_NN}=62.4 GeV and 200 GeV performed with the STAR detector at RHIC. The observed global polarization of Lambda and anti-Lambda hyperons in the STAR acceptance is consistent with zero within the precision of the measurements. The obtained upper limit, |P_{Lambda,anti-Lambda}| <= 0.02, is compared to the theoretical values discussed recently in the literature.

11 data tables

(Color online) Invariant mass distribution for the $\Lambda$ (filled circles) and $\overline{\Lambda}$ (open squares) candidates after the quality cuts for Au+Au collisions at $\sqrt{s_{NN}}$=62.4 GeV (centrality region 0-80%).

(Color online) Global polarization of $\Lambda$–hyperons as a function of $\Lambda$ transverse momentum $p^{\Lambda}_{t}$. Filled circles show the results for Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV (centrality region 20-70%) and open squares indicate the results for Au+Au collisions at $\sqrt{s_{NN}}$=62.4 GeV (centrality region 0-80%). Only statistical uncertainties are shown.

(Color online) Global polarization of $\Lambda$–hyperons as a function of $\Lambda$ pseudorapidity $\eta^{\Lambda}$. Filled circles show the results for Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV (centrality region 20-70%). A constant line fit to these data points yields $P_{\Lambda}=(2.8\pm 9.6)\times 10^{-3}$ with $\chi^{2}/ndf=6.5/10$. Open squares show the results for Au+Au collisions at $\sqrt{s_{NN}}$=62.4 GeV (centrality region 0-80%). A constant line fit gives $P_{\Lambda}=(1.9\pm 8.0)\times 10^{-3}$ with $\chi^{2}/ndf=14.3/10$. Only statistical uncertainties are shown.

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Directed and elliptic flow of charged particles in Cu+Cu collisions at $\sqrt{s_{NN}} =$ 22.4 GeV

The STAR collaboration Agakishiev, G. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.C 85 (2012) 014901, 2012.
Inspire Record 929522 DOI 10.17182/hepdata.98622

This paper reports results for directed flow $v_{1}$ and elliptic flow $v_{2}$ of charged particles in Cu+Cu collisions at $\sqrt{s_{NN}}=$ 22.4 GeV at the Relativistic Heavy Ion Collider. The measurements are for the 0-60% most central collisions, using charged particles observed in the STAR detector. Our measurements extend to 22.4 GeV Cu+Cu collisions the prior observation that $v_1$ is independent of the system size at 62.4 and 200 GeV, and also extend the scaling of $v_1$ with $\eta/y_{\rm beam}$ to this system. The measured $v_2(p_T)$ in Cu+Cu collisions is similar for $\sqrt{s_{NN}} = 22.4-200$ GeV. We also report a comparison with results from transport model (UrQMD and AMPT) calculations. The model results do not agree quantitatively with the measured $v_1(\eta), v_2(p_T)$ and $v_2(\eta)$.

6 data tables

The event plane resolution measured using the TPC (second order) and using the BBC (first order) are shown as a function of collision centrality for Cu+Cu collisions at $\sqrt{s_{NN}}$ = 22.4 GeV. Errors are statistical only.

Charged hadron $v_{1}${BBC} vs. $\eta$ for 0-60% centrality Cu+Cu collisions at $\sqrt{s_{NN}}$ = 22.4 GeV. The errors shown are statistical. Systematic errors are discussed in Section III.C. Results are compared to $v_{1}$ from 0-40% centrality Au+Au collisions at $\sqrt{s_{NN}}$ = 19.6 GeV from the PHOBOS collaboration [10].

Comparison of the measured $v_{1}${BBC} as a function of η in 0-60% Cu+Cu collisions at $\sqrt{s_{NN}}$ = 22.4 GeV with model predictions. The inset shows the central $\eta$ region in more detail. The errors are statistical only.

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Suppression of away-side jet fragments with respect to the reaction plane in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.C 84 (2011) 024904, 2011.
Inspire Record 872172 DOI 10.17182/hepdata.96510

Pair correlations between large transverse momentum neutral pion triggers (p_T=4--7 GeV/c) and charged hadron partners (p_T=3--7 GeV/c) in central (0--20%) and midcentral (20--60%) Au+Au collisions are presented as a function of trigger orientation with respect to the reaction plane. The particles are at larger momentum than where jet shape modifications have been observed, and the correlations are sensitive to the energy loss of partons traveling through hot dense matter. An out-of-plane trigger particle produces only 26+/-20% of the away-side pairs that are observed opposite of an in-plane trigger particle. In contrast, near-side jet fragments are consistent with no suppression or dependence on trigger orientation with respect to the reaction plane. These observations are qualitatively consistent with a picture of little near-side parton energy loss either due to surface bias or fluctuations and increased away-side parton energy loss due to a long path through the medium. The away-side suppression as a function of reaction-plane angle is shown to be sensitive to both the energy loss mechanism in and the space-time evolution of heavy-ion collisions.

22 data tables

Delta phi / Correlation Function 3-4 GeV/c partners

Delta phi / Correlation Function 3-4 GeV/c partners

$p^{a}_{T} = 3-4$ GeV/$c$

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Medium modification of jet fragmentation in Au + Au collisions at $\sqrt{s_{NN}}= 200$ GeV measured in direct photon-hadron correlations

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.Lett. 111 (2013) 032301, 2013.
Inspire Record 1207323 DOI 10.17182/hepdata.95877

The jet fragmentation function is measured with direct photon-hadron correlations in p+p and Au+Au collisions at sqrt(s_NN)=200 GeV. The p_T of the photon is an excellent approximation to the initial p_T of the jet and the ratio z_T=p_T^h/p_T^\gamma is used as a proxy for the jet fragmentation function. A statistical subtraction is used to extract the direct photon-hadron yields in Au+Au collisions while a photon isolation cut is applied in p+p. I_ AA, the ratio of jet fragment yield in Au+Au to that in p+p, indicates modification of the jet fragmentation function. Suppression, most likely due to energy loss in the medium, is seen at high z_T. The fragment yield at low z_T is enhanced at large angles. Such a trend is expected from redistribution of the lost energy into increased production of low-momentum particles.

5 data tables

Direct photon-hadron pair per-trigger yields vs Delta-phi (Au+Au and p+p)

Integrated per-trigger yields and I_AA vs xi

Integrated per-trigger yields and I_AA vs xi

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Measurement of $\phi $ meson production in $p + p$ interactions at 40, 80 and $158 \, \hbox {GeV}/c$ with the NA61/SHINE spectrometer at the CERN SPS

The NA61/SHINE collaboration Aduszkiewicz, A. ; Andronov, E.V. ; Antićić, T. ; et al.
Eur.Phys.J.C 80 (2020) 199, 2020.
Inspire Record 1749613 DOI 10.17182/hepdata.93228

Results on $\phi$ meson production in inelastic p+p collisions at CERN SPS energies are presented. They are derived from data collected by the NA61/SHINE fixed target experiment, by means of invariant mass spectra fits in the $\phi \to K^+K^-$ decay channel. They include the first ever measured double differential spectra of $\phi$ mesons as a function of rapidity $y$ and transverse momentum $p_T$ for proton beam momenta of 80 GeV/c and 158 GeV/c, as well as single differential spectra of $y$ or $p_T$ for beam momentum of 40 GeV/c. The corresponding total $\phi$ yields per inelastic p+p event are obtained. These results are compared with existing data on $\phi$ meson production in p+p collisions. The comparison shows consistency but superior accuracy of the present measurements. The emission of $\phi$ mesons in p+p reactions is confronted with that occurring in Pb+Pb collisions, and the experimental results are compared with model predictions. It appears that none of the considered models can properly describe all the experimental observables.

17 data tables

Double differential multiplicity of $\phi$ mesons produced in minimum bias p+p collisions at beam momentum of 158 GeV/c, as a function of transverse momentum $p_T$ and rapidity $y$.

Double differential multiplicity of $\phi$ mesons produced in minimum bias p+p collisions at beam momentum of 80 GeV/c, as a function of transverse momentum $p_T$ and rapidity $y$.

Transverse momentum $p_T$ spectrum of $\phi$ mesons produced in minimum bias p+p collisions at beam momentum of 40 GeV/c, in a broad rapidity $y$ bin of (0, 1.5).

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Nuclear stopping and rapidity loss in Au+Au collisions at s(NN)**(1/2) = 62.4-GeV

The BRAHMS collaboration Arsene, I.C. ; Bearden, I.G. ; Beavis, D. ; et al.
Phys.Lett.B 677 (2009) 267-271, 2009.
Inspire Record 810481 DOI 10.17182/hepdata.89449

Transverse momentum spectra of protons and anti-protons measured in the rapidity range 0<y<3.1 from 0-10% central Au+Au collisions at sqrt{s_{NN}}=62.4 GeV are presented. The rapidity densities, dN/dy, of protons, anti-protons and net-protons N()p-N(pbar) have been deduced from the spectra over a rapidity range wide enough to observe the expected maximum net-baryon density. From mid-rapidity to y=1 the net-proton yield is roughly constant (dN/dy ~ 10),but rises to dN/dy ~25 at 2.3<y<3.1. The mean rapidity loss is 2.01 +-0.16 units from beam rapidity. The measured rapidity distributions are compared to model predictions. Systematics of net-baryon distributions and rapidity loss vs. collision energy are discussed.

16 data tables

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$ versus $p_{\mathrm{T}}$ for $\mathrm{p}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=62.4\,\mathrm{Ge\!V}$ near $y=-0.1-0.1$

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$ versus $p_{\mathrm{T}}$ for $\overline{\mathrm{p}}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=62.4\,\mathrm{Ge\!V}$ near $y=-0.1-0.1$

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$ versus $p_{\mathrm{T}}$ for $\mathrm{p}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=62.4\,\mathrm{Ge\!V}$ near $y=0.4-0.9$

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Single Transverse Spin Asymmetries of Identified Charged Hadrons in Polarized p+p Collisions at s**(1/2) = 62.4-GeV

The BRAHMS collaboration Arsene, I. ; Bearden, I.G. ; Beavis, Dana Richard ; et al.
Phys.Rev.Lett. 101 (2008) 042001, 2008.
Inspire Record 776954 DOI 10.17182/hepdata.89448

The first measurements of $x_F$-dependent single spin asymmetries of identified charged hadrons, $\pi^{\pm}$, $K^{\pm}$, and protons, from transversely polarized proton-proton collisions at 62.4 GeV at RHIC are presented. The measurements extend to high-$x_F$ ($|x_F|\sim 0.6$) in both the forward and backward directions.Large asymmetries are seen in the pion and kaon channels. The asymmetries in inclusive $\pi^{+}$ production, $A_N(\pi^+)$, increase with $x_F$ from 0 to $\sim$0.25 %at $x_F = 0.6$ and $A_N(\pi^{-})$ decrease from 0 to $\sim$$-$0.4. Even though $K^-$ contains no valence quarks, observed asymmetries for $K^-$ unexpectedly show positive values similar to those for $K^+$, increasing with $x_F$, whereas proton asymmetries are consistent with zero over the measured kinematic range. Comparisons of the data with predictions of QCD-based models are presented. The flavor dependent single spin asymmetry measurements of identified hadrons allow for stringent tests of theoretical models of partonic dynamics in the RHIC energy regime.

17 data tables

$A_{N}$ versus $x_{\mathrm{F}}$ for $\mathrm{\pi}^{-}$ in $\mathrm{p}\mathrm{p}$ at $\sqrt{s}=62.4\,\mathrm{Ge\!V}$

$A_{N}$ versus $x_{\mathrm{F}}$ for $\mathrm{\pi}^{-}$ in $\mathrm{p}\mathrm{p}$ at $\sqrt{s}=62.4\,\mathrm{Ge\!V}$

$A_{N}$ versus $x_{\mathrm{F}}$ for $\mathrm{\pi}^{+}$ in $\mathrm{p}\mathrm{p}$ at $\sqrt{s}=62.4\,\mathrm{Ge\!V}$

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Production of deuterium, tritium, and He3 in central Pb + Pb collisions at 20A,30A,40A,80A , and 158A GeV at the CERN Super Proton Synchrotron

The NA49 collaboration Anticic, T. ; Baatar, B. ; Bartke, J. ; et al.
Phys.Rev.C 94 (2016) 044906, 2016.
Inspire Record 1469272 DOI 10.17182/hepdata.88359

Production of $d$, $t$, and $^3$He nuclei in central Pb+Pb interactions was studied at five collision energies ($\sqrt{s_{NN}}=$ 6.3, 7.6, 8.8, 12.3, and 17.3 GeV) with the NA49 detector at the CERN SPS. Transverse momentum spectra, rapidity distributions, and particle ratios were measured. Yields are compared to predictions of statistical models. Phase-space distributions of light nuclei are discussed and compared to those of protons in the context of a coalescence approach. The coalescence parameters $B_2$ and $B_3$, as well as coalescence radii for $d$ and $^3$He were determined as a function of transverse mass at all energies.

103 data tables

Numerical data for the transverse momentum spectra of helium-3 in rapidity interval

Numerical data for the transverse momentum spectra of helium-3 in rapidity interval

Numerical data for the transverse momentum spectra of helium-3 in rapidity interval

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Version 2
Multiplicity and transverse momentum fluctuations in inelastic proton–proton interactions at the CERN Super Proton Synchrotron

The NA61/SHINE collaboration Aduszkiewicz, A. ; Ali, Y. ; Andronov, E. ; et al.
Eur.Phys.J.C 76 (2016) 635, 2016.
Inspire Record 1395611 DOI 10.17182/hepdata.76900

Measurements of multiplicity and transverse momentum fluctuations of charged particles were performed in inelastic p+p interactions at 20, 31, 40, 80 and 158 GeV/c beam momentum. Results for the scaled variance of the multiplicity distribution and for three strongly intensive measures of multiplicity and transverse momentum fluctuations \$\Delta[P_{T},N]\$, \$\Sigma[P_{T},N]\$ and \$\Phi_{p_T}\$ are presented. For the first time the results on fluctuations are fully corrected for experimental biases. The results on multiplicity and transverse momentum fluctuations significantly deviate from expectations for the independent particle production. They also depend on charges of selected hadrons. The string-resonance Monte Carlo models EPOS and UrQMD do not describe the data. The scaled variance of multiplicity fluctuations is significantly higher in inelastic p+p interactions than in central Pb+Pb collisions measured by NA49 at the same energy per nucleon. This is in qualitative disagreement with the predictions of the Wounded Nucleon Model. Within the statistical framework the enhanced multiplicity fluctuations in inelastic p+p interactions can be interpreted as due to event-by-event fluctuations of the fireball energy and/or volume.

14 data tables

Energy dependence of $\Delta[P_{T},N]$ for three charge selections

Energy dependence of $\Delta[P_{T},N]$ for three charge selections

Energy dependence of $\Sigma[P_{T},N]$ for three chrge selections

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Version 2
High Transverse Momentum Prompt Photon Production by $\pi^-$ and $\pi^+$ on Protons at 280-{GeV}/$c$

The WA70 collaboration Bonesini, M. ; Bonvin, E. ; Boóth, P.S. L. ; et al.
Z.Phys.C 37 (1988) 535, 1988.
Inspire Record 250394 DOI 10.17182/hepdata.15649

The inclusive cross sections for prompt photon production by π− and π+ on protons have been measured with a beam momentum of 280 GeV/c using a fine grained electromagnetic calorimeter and the CERN Omega spectrometer. The transverse momentum and FeynmanxF ranges covered are 4.0<pT<7.0GeV/c and −0.45<xF<0.55 respectively. A quantitative comparison of the prompt photon cross section with next-to-leading order QCD predictions using Duke and Owens structure functions is performed.

8 data tables

Invariant cross section.

Invariant cross section.

PT DISTRIBUTIONS FOR SELECTED XF INTERVALS.

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Light isovector resonances in $\pi^- p \to \pi^-\pi^-\pi^+ p$ at 190 GeV/${\it c}$

The COMPASS collaboration Aghasyan, M. ; Alexeev, M.G. ; Alexeev, G.D. ; et al.
Phys.Rev.D 98 (2018) 092003, 2018.
Inspire Record 1655631 DOI 10.17182/hepdata.82958

We have performed the most comprehensive resonance-model fit of $\pi^-\pi^-\pi^+$ states using the results of our previously published partial-wave analysis (PWA) of a large data set of diffractive-dissociation events from the reaction $\pi^- + p \to \pi^-\pi^-\pi^+ + p_\text{recoil}$ with a 190 GeV/$c$ pion beam. The PWA results, which were obtained in 100 bins of three-pion mass, $0.5 &lt; m_{3\pi} &lt; 2.5$ GeV/$c^2$, and simultaneously in 11 bins of the reduced four-momentum transfer squared, $0.1 &lt; t' &lt; 1.0$ $($GeV$/c)^2$, are subjected to a resonance-model fit using Breit-Wigner amplitudes to simultaneously describe a subset of 14 selected waves using 11 isovector light-meson states with $J^{PC} = 0^{-+}$, $1^{++}$, $2^{++}$, $2^{-+}$, $4^{++}$, and spin-exotic $1^{-+}$ quantum numbers. The model contains the well-known resonances $\pi(1800)$, $a_1(1260)$, $a_2(1320)$, $\pi_2(1670)$, $\pi_2(1880)$, and $a_4(2040)$. In addition, it includes the disputed $\pi_1(1600)$, the excited states $a_1(1640)$, $a_2(1700)$, and $\pi_2(2005)$, as well as the resonancelike $a_1(1420)$. We measure the resonance parameters mass and width of these objects by combining the information from the PWA results obtained in the 11 $t'$ bins. We extract the relative branching fractions of the $\rho(770) \pi$ and $f_2(1270) \pi$ decays of $a_2(1320)$ and $a_4(2040)$, where the former one is measured for the first time. In a novel approach, we extract the $t'$ dependence of the intensity of the resonances and of their phases. The $t'$ dependence of the intensities of most resonances differs distinctly from the $t'$ dependence of the nonresonant components. For the first time, we determine the $t'$ dependence of the phases of the production amplitudes and confirm that the production mechanism of the Pomeron exchange is common to all resonances.

2 data tables

Real and imaginary parts of the normalized transition amplitudes $\mathcal{T}_a$ of the 14 selected partial waves in the 1100 $(m_{3\pi}, t')$ cells (see Eq. (12) in the paper). The wave index $a$ represents the quantum numbers that uniquely define the partial wave. The quantum numbers are given by the shorthand notation $J^{PC} M^\varepsilon [$isobar$] \pi L$. We use this notation to label the transition amplitudes in the column headers. The $m_{3\pi}$ values that are given in the first column correspond to the bin centers. Each of the 100 $m_{3\pi}$ bins is 20 MeV/$c^2$ wide. Since the 11 $t'$ bins are non-equidistant, the lower and upper bounds of each $t'$ bin are given in the column headers. The transition amplitudes define the spin-density matrix elements $\varrho_{ab}$ for waves $a$ and $b$ according to Eq. (18). The spin-density matrix enters the resonance-model fit via Eqs. (33) and (34). The transition amplitudes are normalized via Eqs. (9), (16), and (17) such that the partial-wave intensities $\varrho_{aa} = |\mathcal{T}_a|^2$ are given in units of acceptance-corrected number of events. The relative phase $\Delta\phi_{ab}$ between two waves $a$ and $b$ is given by $\arg(\varrho_{ab}) = \arg(\mathcal{T}_a) - \arg(\mathcal{T}_b)$. Note that only relative phases are well-defined. The phase of the $1^{++}0^+ \rho(770) \pi S$ wave was set to $0^\circ$ so that the corresponding transition amplitudes are real-valued. In the PWA model, some waves are excluded in the region of low $m_{3\pi}$ (see paper and [Phys. Rev. D 95, 032004 (2017)] for a detailed description of the PWA model). For these waves, the transition amplitudes are set to zero. The tables with the covariance matrices of the transition amplitudes for all 1100 $(m_{3\pi}, t')$ cells can be downloaded via the 'Additional Resources' for this table.

Decay phase-space volume $I_{aa}$ for the 14 selected partial waves as a function of $m_{3\pi}$, normalized such that $I_{aa}(m_{3\pi} = 2.5~\text{GeV}/c^2) = 1$. The wave index $a$ represents the quantum numbers that uniquely define the partial wave. The quantum numbers are given by the shorthand notation $J^{PC} M^\varepsilon [$isobar$] \pi L$. We use this notation to label the decay phase-space volume in the column headers. The labels are identical to the ones used in the column headers of the table of the transition amplitudes. $I_{aa}$ is calculated using Monte Carlo integration techniques for fixed $m_{3\pi}$ values, which are given in the first column, in the range from 0.5 to 2.5 GeV/$c^2$ in steps of 10 MeV/$c^2$. The statistical uncertainties given for $I_{aa}$ are due to the finite number of Monte Carlo events. $I_{aa}(m_{3\pi})$ is defined in Eq. (6) in the paper and appears in the resonance model in Eqs. (19) and (20).


Update of the ALEPH non-strange spectral functions from hadronic $\tau$ decays

Davier, Michel ; Höcker, Andreas ; Malaescu, Bogdan ; et al.
Eur.Phys.J.C 74 (2014) 2803, 2014.
Inspire Record 1267648 DOI 10.17182/hepdata.77010

An update of the ALEPH non-strange spectral functions from hadronic $\tau$ decays is presented. Compared to the 2005 ALEPH publication, the main improvement is related to the use of a new method to unfold the measured mass spectra from detector effects. This procedure also corrects a previous problem in the correlations between the unfolded mass bins. Results from QCD studies and for the evaluation of the hadronic vacuum polarisation contribution to the anomalous muon magnetic moment are derived using the new spectral functions. They are found in agreement with published results based on the previous set of spectral functions.

23 data tables

Differential mass squared cross section for the $\pi\pi^0$ channel presented here as the cross section multipled by the bin width. The data are normalised to a branching ratio of 25.471%

Differential mass squared cross section for the $\pi 2\pi^0$ channel presented here as the cross section multipled by the bin width. The data are normalised to a branching ratio of 9.239%

Differential mass squared cross section for the $\pi 3\pi^0$ channel presented here as the cross section multipled by the bin width. The data are normalised to a branching ratio of 0.977%

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Two-particle correlations in azimuthal angle and pseudorapidity in inelastic p + p interactions at the CERN Super Proton Synchrotron

The NA61/SHINE collaboration Aduszkiewicz, A. ; Ali, Y. ; Andronov, E. ; et al.
Eur.Phys.J.C 77 (2017) 59, 2017.
Inspire Record 1489238 DOI 10.17182/hepdata.76899

Results on two-particle $\Delta\eta\Delta\phi$ correlations in inelastic p+p interactions at 20, 31, 40, 80, and 158~GeV/c are presented. The measurements were performed using the large acceptance NA61/SHINE hadron spectrometer at the CERN Super Proton Synchrotron. The data show structures which can be attributed mainly to effects of resonance decays, momentum conservation, and quantum statistics. The results are compared with the EPOS and UrQMD models.

20 data tables

Two-particle correlation function C(Delta eta, Delta phi) for all charge pairs in inelastic p+p interactions at 20 GeV/c.

Two-particle correlation function C(Delta eta, Delta phi) for all charge pairs in inelastic p+p interactions at 31 GeV/c.

Two-particle correlation function C(Delta eta, Delta phi) for all charge pairs in inelastic p+p interactions at 40 GeV/c.

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Measurements of $\pi ^\pm $ , K$^\pm $ , p and ${\bar{\text {p}}}$ spectra in proton-proton interactions at 20, 31, 40, 80 and 158 $\text{ GeV}/c$ with the NA61/SHINE spectrometer at the CERN SPS

The NA61/SHINE collaboration Aduszkiewicz, A. ; Ali, Y. ; Andronov, E. ; et al.
Eur.Phys.J.C 77 (2017) 671, 2017.
Inspire Record 1598505 DOI 10.17182/hepdata.79533

Measurements of inclusive spectra and mean multiplicities of $\pi^\pm$, K$^\pm$, p and $\bar{\textrm{p}}$ produced in inelastic p+p interactions at incident projectile momenta of 20, 31, 40, 80 and 158 GeV/c ($\sqrt{s} = $ 6.3, 7.7, 8.8, 12.3 and 17.3 GeV, respectively) were performed at the CERN Super Proton Synchrotron using the large acceptance NA61/SHINE hadron spectrometer. Spectra are presented as function of rapidity and transverse momentum and are compared to predictions of current models. The measurements serve as the baseline in the NA61/SHINE study of the properties of the onset of deconfinement and search for the critical point of strongly interacting matter.

116 data tables

Transverse momentum-rapidity spectrum of K− produced in inelastic p+p interactions at 31 GeV/c with statistical uncertainties.

Transverse momentum-rapidity spectrum of K− produced in inelastic p+p interactions at 20 GeV/c with systematic uncertainties.

Transverse momentum-rapidity spectrum of K+ produced in inelastic p+p interactions at 20 GeV/c with statistical uncertainties.

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Energy dependence of forward-rapidity $\mathrm {J}/\psi $ and $\psi \mathrm {(2S)}$ production in pp collisions at the LHC

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
Eur.Phys.J.C 77 (2017) 392, 2017.
Inspire Record 1511865 DOI 10.17182/hepdata.77781

We present results on transverse momentum ($p_{\rm T}$) and rapidity ($y$) differential production cross sections, mean transverse momentum and mean transverse momentum square of inclusive J/$\psi$ and $\psi(2S)$ at forward rapidity ($2.5<y<4$) as well as $\psi(2S)$-to-J/$\psi$ cross section ratios. These quantities are measured in pp collisions at center of mass energies $\sqrt{s}=5.02$ and 13 TeV with the ALICE detector. Both charmonium states are reconstructed in the dimuon decay channel, using the muon spectrometer. A comprehensive comparison to inclusive charmonium cross sections measured at $\sqrt{s}=2.76$, 7 and 8 TeV is performed. A comparison to non-relativistic quantum chromodynamics and fixed-order next-to-leading logarithm calculations, which describe prompt and non-prompt charmonium production respectively, is also presented. A good description of the data is obtained over the full $p_{\rm T}$ range, provided that both contributions are summed. In particular, it is found that for $p_{\rm T}>15$ GeV/$c$ the non-prompt contribution reaches up to 50% of the total charmonium yield.

14 data tables

Differential production cross sections of $J/\psi$ as a function of $p_{\rm T}$.

Differential production cross sections of $J/\psi$ as a function of rapidity.

Differential production cross sections of $\psi(2S)$ as a function of $p_{\rm T}$.

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System size and energy dependence of near-side di-hadron correlations

The STAR collaboration Agakishiev, G. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.C 85 (2012) 014903, 2012.
Inspire Record 943192 DOI 10.17182/hepdata.77720

Two-particle azimuthal ($\Delta\phi$) and pseudorapidity ($\Delta\eta$) correlations using a trigger particle with large transverse momentum ($p_T$) in $d$+Au, Cu+Cu and Au+Au collisions at $\sqrt{s_{{NN}}}$ =\xspace 62.4 GeV and 200~GeV from the STAR experiment at RHIC are presented. The \ns correlation is separated into a jet-like component, narrow in both $\Delta\phi$ and $\Delta\eta$, and the ridge, narrow in $\Delta\phi$ but broad in $\Delta\eta$. Both components are studied as a function of collision centrality, and the jet-like correlation is studied as a function of the trigger and associated $p_T$. The behavior of the jet-like component is remarkably consistent for different collision systems, suggesting it is produced by fragmentation. The width of the jet-like correlation is found to increase with the system size. The ridge, previously observed in Au+Au collisions at $\sqrt{s_{{NN}}}$ = 200 GeV, is also found in Cu+Cu collisions and in collisions at $\sqrt{s_{{NN}}}$ =\xspace 62.4 GeV, but is found to be substantially smaller at $\sqrt{s_{{NN}}}$ =\xspace 62.4 GeV than at $\sqrt{s_{{NN}}}$ = 200 GeV for the same average number of participants ($ \langle N_{\mathrm{part}}\rangle$). Measurements of the ridge are compared to models.

40 data tables

Parameterizations of the transverse momentum dependence of the reconstruction efficiency of charged particles in the TPC in various collision systems, energies and centrality bins for the track selection cuts used in this analysis.

The raw correlation in $\Delta\eta$ for di-hadron correlations for 3 $<$ $p_T^{trigger}$ $<$ 6 GeV/$c$ and 1.5 GeV/$c$ $<$ $p_T^{associated}$ $<$ $p_T^{trigger}$ for 0-12% central \Au collisions for $|\Delta\phi|<$ 0.78 before and after the track merging correction is applied. The data have been reflected about $\Delta\eta$=0.

Sample correlations in $\Delta\eta$ ($|\Delta\phi|<$ 0.78) for 3 $<$ $p_T^{trigger}$ $<$ 6 GeV/$c$ and 1.5 GeV/$c$ $<$ $p_T^{associated}$ $<$ $p_T^{trigger}$ for 0-60% Cu+Cu at $\sqrt{s_{NN}}$ = 62.4 GeV, 0-80% Au+Au at $\sqrt{s_{NN}}$ = 62.4 GeV, 0-95% $d$+Au at $\sqrt{s_{NN}}$ = 200 GeV, 0-60% Cu+Cu at $\sqrt{s_{NN}}$ = 200 GeV, 40-80% Au+Au at $\sqrt{s_{NN}}$ = 200 GeV, and 0-12% central Au+Au at $\sqrt{s_{NN}}$ = 200 GeV. The data are averaged between positive and negative $\Delta\eta$. 5% systematic uncertainty due to track reconstruction efficiency not listed below.