cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.17182/hepdata.142075.v1/t5
title: "Figure 9" of "$\phi$ meson production in the forward/backward rapidity region in Cu$+$Au collisions at $\sqrt{s_{NN}}=200$ GeV"

description: The nuclear modification factor $R_{CuAu}$ as a function of the number of participating nucleons for 1.2 &lt; $|y|$ &lt; 2.2 and 1 &lt; $p_T$ &lt; 5 GeV/$c$. Type A represents uncertainties that are uncorrelated from point to point, Type B represents uncertainties that are correlated from point to point, and Type C represents uncertainties in the overall normalization.
description: The PHENIX experiment at the Relativistic Heavy Ion Collider has measured $\phi$ meson production and its nuclear modification in asymmetric Cu+Au heavy-ion collisions at $\sqrt{s_{NN}}$ = 200 GeV at both forward Cu-going direction (1.2 &lt; $y$ &lt; 2.2) and backward Au-going direction (−2.2 &lt; $y$ &lt; −1.2), rapidities. The measurements are performed via the dimuon decay channel and reported as a function of the number of participating nucleons, rapidity, and transverse momentum. In the most central events, 0%–20% centrality, the $\phi$ meson yield integrated over 1 &lt; $p_T$ &lt; 5 GeV/$c$ prefers a smaller value, which means a larger nuclear modification, in the Cu-going direction compared to the Au-going direction. Additionally, the nuclear-modification factor in Cu+Au collisions averaged over all centrality is measured to be similar to the previous PHENIX result in $d$+Au collisions for these rapidities.
DOI: 10.17182/hepdata.142075.v1/t6
title: "Figure 10" of "$\phi$ meson production in the forward/backward rapidity region in Cu$+$Au collisions at $\sqrt{s_{NN}}=200$ GeV"

description: The nuclear modification factor $R_{CuAu}$ as a function of rapidity for 1 &lt; $p_T$ &lt; 5 GeV/$c$ and 0%– 93% centrality. Type A represents uncertainties that are uncorrelated from point to point, Type B represents uncertainties that are correlated from point to point, and Type C represents uncertainties in the overall normalization.
description: The PHENIX experiment at the Relativistic Heavy Ion Collider has measured $\phi$ meson production and its nuclear modification in asymmetric Cu+Au heavy-ion collisions at $\sqrt{s_{NN}}$ = 200 GeV at both forward Cu-going direction (1.2 &lt; $y$ &lt; 2.2) and backward Au-going direction (−2.2 &lt; $y$ &lt; −1.2), rapidities. The measurements are performed via the dimuon decay channel and reported as a function of the number of participating nucleons, rapidity, and transverse momentum. In the most central events, 0%–20% centrality, the $\phi$ meson yield integrated over 1 &lt; $p_T$ &lt; 5 GeV/$c$ prefers a smaller value, which means a larger nuclear modification, in the Cu-going direction compared to the Au-going direction. Additionally, the nuclear-modification factor in Cu+Au collisions averaged over all centrality is measured to be similar to the previous PHENIX result in $d$+Au collisions for these rapidities.
DOI: 10.17182/hepdata.142075.v1/t7
title: "Figure 11" of "$\phi$ meson production in the forward/backward rapidity region in Cu$+$Au collisions at $\sqrt{s_{NN}}=200$ GeV"

description: The forward/backward ratio as a function of the number of participating nucleons for 1 &lt; $p_T$ &lt; 5 GeV/$c$ and 1.2 &lt; $|y|$ &lt; 2.2. Type A represents uncertainties that are uncorrelated from point to point and Type B represents uncertainties that are correlated from point to point. For the B sys. error for centrality 0-20% forward/backward ratio 0.20, the value is $\pm$ &lt; 0.10.
description: The PHENIX experiment at the Relativistic Heavy Ion Collider has measured $\phi$ meson production and its nuclear modification in asymmetric Cu+Au heavy-ion collisions at $\sqrt{s_{NN}}$ = 200 GeV at both forward Cu-going direction (1.2 &lt; $y$ &lt; 2.2) and backward Au-going direction (−2.2 &lt; $y$ &lt; −1.2), rapidities. The measurements are performed via the dimuon decay channel and reported as a function of the number of participating nucleons, rapidity, and transverse momentum. In the most central events, 0%–20% centrality, the $\phi$ meson yield integrated over 1 &lt; $p_T$ &lt; 5 GeV/$c$ prefers a smaller value, which means a larger nuclear modification, in the Cu-going direction compared to the Au-going direction. Additionally, the nuclear-modification factor in Cu+Au collisions averaged over all centrality is measured to be similar to the previous PHENIX result in $d$+Au collisions for these rapidities.
DOI: 10.17182/hepdata.142076.v1/t1
title: "Figure 1" of "Inclusive cross section and double helicity asymmetry for pi^0 production in p+p collisions at sqrt(s) = 62.4 GeV"

description: The fraction of inclusive $\pi^0$ yield which satisfied the BBC trigger condition.
description: The PHENIX experiment presents results from the RHIC 2006 run with polarized $p + p$ collisions at $\sqrt{s}$ = 62.4 GeV, for inclusive $\pi^0$ production at mid-rapidity. Unpolarized cross section results are measured for transverse momenta $p_T$ = 0.5 to 7 GeV/$c$. Next-to-leading order perturbative quantum chromodynamics calculations are compared with the data, and while the calculations are consistent with the measurements, next-to-leading logarithmic corrections improve the agreement. Double helicity asymmetries ALL are presented for $p_T$ = 1 to 4 GeV/$c$ and probe the higher range of Bjorken $x$ of the gluon ($x_g$) with better statistical precision than our previous measurements at $\sqrt{s}$ = 200 GeV. These measurements are sensitive to the gluon production in the proton for 0.06 &lt; $x_g$ &lt; 0.4.
DOI: 10.15468/dl.jufc9k
title: Occurrence Download

description: A dataset containing 4487 species occurrences available in GBIF matching the query:
{
 "and" : [
 "OccurrenceStatus is Present",
 "TaxonKey is Pinus longaeva"
 ]
}

 The dataset includes 4487 records from 102 constituent datasets; see https://api.gbif.org/v1/occurrence/download/0016000-251025141854904/datasets/export for details.
 
Data from some individual datasets included in this download may be licensed under less restrictive terms.
DOI: 10.17182/hepdata.142076.v1/t2
title: "Figure 3" of "Inclusive cross section and double helicity asymmetry for pi^0 production in p+p collisions at sqrt(s) = 62.4 GeV"

description: The neutral pion production cross section at $\sqrt{s}$ = 62.4 GeV as a function of $p_T$ and the results of next-to-leading order (NLO) and next-to-leading logarithmic accuracy (NLL) perturbative Quantum Chromodynamics (pQCD) calculations for the theory scale $\mu$ = $p_T$.
description: The PHENIX experiment presents results from the RHIC 2006 run with polarized $p + p$ collisions at $\sqrt{s}$ = 62.4 GeV, for inclusive $\pi^0$ production at mid-rapidity. Unpolarized cross section results are measured for transverse momenta $p_T$ = 0.5 to 7 GeV/$c$. Next-to-leading order perturbative quantum chromodynamics calculations are compared with the data, and while the calculations are consistent with the measurements, next-to-leading logarithmic corrections improve the agreement. Double helicity asymmetries ALL are presented for $p_T$ = 1 to 4 GeV/$c$ and probe the higher range of Bjorken $x$ of the gluon ($x_g$) with better statistical precision than our previous measurements at $\sqrt{s}$ = 200 GeV. These measurements are sensitive to the gluon production in the proton for 0.06 &lt; $x_g$ &lt; 0.4.
DOI: 10.17182/hepdata.142076.v1/t3
title: "Figure 4" of "Inclusive cross section and double helicity asymmetry for pi^0 production in p+p collisions at sqrt(s) = 62.4 GeV"

description: The parameter $n$ obtained from the ratio of invariant cross section at $\sqrt{s}$ = 62.4 GeV and $\sqrt{s}$ = 200GeV, at each $x_T$ of $\sqrt{s}$ = 62.4 GeV data; error bars show the statistical and systematic uncertainties of the $\sqrt{s}$ = 62.4 GeV and $\sqrt{s}$ = 200 GeV data.
description: The PHENIX experiment presents results from the RHIC 2006 run with polarized $p + p$ collisions at $\sqrt{s}$ = 62.4 GeV, for inclusive $\pi^0$ production at mid-rapidity. Unpolarized cross section results are measured for transverse momenta $p_T$ = 0.5 to 7 GeV/$c$. Next-to-leading order perturbative quantum chromodynamics calculations are compared with the data, and while the calculations are consistent with the measurements, next-to-leading logarithmic corrections improve the agreement. Double helicity asymmetries ALL are presented for $p_T$ = 1 to 4 GeV/$c$ and probe the higher range of Bjorken $x$ of the gluon ($x_g$) with better statistical precision than our previous measurements at $\sqrt{s}$ = 200 GeV. These measurements are sensitive to the gluon production in the proton for 0.06 &lt; $x_g$ &lt; 0.4.
DOI: 10.17182/hepdata.142076.v1/t4
title: "Table 5" of "Inclusive cross section and double helicity asymmetry for pi^0 production in p+p collisions at sqrt(s) = 62.4 GeV"

description: The double helicity asymmetry for neutral pion production at $\sqrt{s}$ = 62.4 GeV as a function $p_T$ (GeV/$c$). Error bars are statistical uncertainties. The point-to-point experimental systematic uncertainties are negligible. Not included in the figure/table are the correlated for all points scale systematic uncertainty of 14% (scales both the values and point-to-point uncertainties by the same factor).
description: The PHENIX experiment presents results from the RHIC 2006 run with polarized $p + p$ collisions at $\sqrt{s}$ = 62.4 GeV, for inclusive $\pi^0$ production at mid-rapidity. Unpolarized cross section results are measured for transverse momenta $p_T$ = 0.5 to 7 GeV/$c$. Next-to-leading order perturbative quantum chromodynamics calculations are compared with the data, and while the calculations are consistent with the measurements, next-to-leading logarithmic corrections improve the agreement. Double helicity asymmetries ALL are presented for $p_T$ = 1 to 4 GeV/$c$ and probe the higher range of Bjorken $x$ of the gluon ($x_g$) with better statistical precision than our previous measurements at $\sqrt{s}$ = 200 GeV. These measurements are sensitive to the gluon production in the proton for 0.06 &lt; $x_g$ &lt; 0.4.
DOI: 10.17182/hepdata.142077.v1/t1
title: "Figure 4-1" of "Transverse-Momentum Dependence of the J/psi Nuclear Modification in d+Au Collisions at sqrt(s_NN)=200 GeV"

description: $J/\psi$ invariant yield as a function of $p_T$ for $p+p$ and 0–100% centrality integrated $d$+Au collisions. The type C systematic uncertainty for each distribution is given as a percentage in the legend. Type A represents uncertainties that are uncorrelated from point to point, Type B represents uncertainties that are correlated from point to point, and Type C represents uncertainties in the overall normalization.
description: We present measured $J/\psi$ production rates in $d$+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV over a broad range of transverse momentum ($p_T$ = 0–14 GeV/$c$) and rapidity (−2.2 &lt; y &lt; 2.2). We construct the nuclear-modification factor $R_{dAu}$ for these kinematics and as a function of collision centrality (related to impact parameter for the $R_{dAu}$ collision). We find that the modification is largest for collisions with small impact parameters, and observe a suppression ($R_{dAu}$ &lt; 1) for $p_T$ &lt; 4 GeV/$c$ at positive rapidities. At negative rapidity we observe a suppression for $p_T$ &lt; 2 GeV/$c$ then an enhancement ($R_{dAu}$ &gt; 1) for pT &gt; 2 GeV/$c$. The observed enhancement at negative rapidity has implications for the observed modification in heavy-ion collisions at high $p_T$.
DOI: 10.17182/hepdata.142077.v1/t2
title: "Figure 4-2" of "Transverse-Momentum Dependence of the J/psi Nuclear Modification in d+Au Collisions at sqrt(s_NN)=200 GeV"

description: $J/\psi$ invariant yield as a function of $p_T$ for $p+p$ and 0–100% centrality integrated $d$+Au collisions. The type C systematic uncertainty for each distribution is given as a percentage in the legend. Type A represents uncertainties that are uncorrelated from point to point, Type B represents uncertainties that are correlated from point to point, and Type C represents uncertainties in the overall normalization.
description: We present measured $J/\psi$ production rates in $d$+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV over a broad range of transverse momentum ($p_T$ = 0–14 GeV/$c$) and rapidity (−2.2 &lt; y &lt; 2.2). We construct the nuclear-modification factor $R_{dAu}$ for these kinematics and as a function of collision centrality (related to impact parameter for the $R_{dAu}$ collision). We find that the modification is largest for collisions with small impact parameters, and observe a suppression ($R_{dAu}$ &lt; 1) for $p_T$ &lt; 4 GeV/$c$ at positive rapidities. At negative rapidity we observe a suppression for $p_T$ &lt; 2 GeV/$c$ then an enhancement ($R_{dAu}$ &gt; 1) for pT &gt; 2 GeV/$c$. The observed enhancement at negative rapidity has implications for the observed modification in heavy-ion collisions at high $p_T$.
DOI: 10.17182/hepdata.142077.v1/t3
title: "Figure 4-3" of "Transverse-Momentum Dependence of the J/psi Nuclear Modification in d+Au Collisions at sqrt(s_NN)=200 GeV"

description: $J/\psi$ invariant yield as a function of $p_T$ for $p+p$ and 0–100% centrality integrated $d$+Au collisions. The type C systematic uncertainty for each distribution is given as a percentage in the legend.Type A represents uncertainties that are uncorrelated from point to point, Type B represents uncertainties that are correlated from point to point, and Type C represents uncertainties in the overall normalization.
description: We present measured $J/\psi$ production rates in $d$+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV over a broad range of transverse momentum ($p_T$ = 0–14 GeV/$c$) and rapidity (−2.2 &lt; y &lt; 2.2). We construct the nuclear-modification factor $R_{dAu}$ for these kinematics and as a function of collision centrality (related to impact parameter for the $R_{dAu}$ collision). We find that the modification is largest for collisions with small impact parameters, and observe a suppression ($R_{dAu}$ &lt; 1) for $p_T$ &lt; 4 GeV/$c$ at positive rapidities. At negative rapidity we observe a suppression for $p_T$ &lt; 2 GeV/$c$ then an enhancement ($R_{dAu}$ &gt; 1) for pT &gt; 2 GeV/$c$. The observed enhancement at negative rapidity has implications for the observed modification in heavy-ion collisions at high $p_T$.
DOI: 10.17182/hepdata.142077.v1/t4
title: "Figure 5-1" of "Transverse-Momentum Dependence of the J/psi Nuclear Modification in d+Au Collisions at sqrt(s_NN)=200 GeV"

description: $J/\psi$ invariant yield as a function of $p_T$ for each centrality at $|y|$ &lt; 0.35. The type C systematic uncertainty for each distribution is given as a percentage in the legend. Type A represents uncertainties that are uncorrelated from point to point, Type B represents uncertainties that are correlated from point to point, and Type C represents uncertainties in the overall normalization.
description: We present measured $J/\psi$ production rates in $d$+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV over a broad range of transverse momentum ($p_T$ = 0–14 GeV/$c$) and rapidity (−2.2 &lt; y &lt; 2.2). We construct the nuclear-modification factor $R_{dAu}$ for these kinematics and as a function of collision centrality (related to impact parameter for the $R_{dAu}$ collision). We find that the modification is largest for collisions with small impact parameters, and observe a suppression ($R_{dAu}$ &lt; 1) for $p_T$ &lt; 4 GeV/$c$ at positive rapidities. At negative rapidity we observe a suppression for $p_T$ &lt; 2 GeV/$c$ then an enhancement ($R_{dAu}$ &gt; 1) for pT &gt; 2 GeV/$c$. The observed enhancement at negative rapidity has implications for the observed modification in heavy-ion collisions at high $p_T$.
DOI: 10.17182/hepdata.142077.v1/t5
title: "Figure 5-2" of "Transverse-Momentum Dependence of the J/psi Nuclear Modification in d+Au Collisions at sqrt(s_NN)=200 GeV"

description: $J/\psi$ invariant yield as a function of $p_T$ for each centrality at $|y|$ &lt; 0.35. The type C systematic uncertainty for each distribution is given as a percentage in the legend. Type A represents uncertainties that are uncorrelated from point to point, Type B represents uncertainties that are correlated from point to point, and Type C represents uncertainties in the overall normalization.
description: We present measured $J/\psi$ production rates in $d$+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV over a broad range of transverse momentum ($p_T$ = 0–14 GeV/$c$) and rapidity (−2.2 &lt; y &lt; 2.2). We construct the nuclear-modification factor $R_{dAu}$ for these kinematics and as a function of collision centrality (related to impact parameter for the $R_{dAu}$ collision). We find that the modification is largest for collisions with small impact parameters, and observe a suppression ($R_{dAu}$ &lt; 1) for $p_T$ &lt; 4 GeV/$c$ at positive rapidities. At negative rapidity we observe a suppression for $p_T$ &lt; 2 GeV/$c$ then an enhancement ($R_{dAu}$ &gt; 1) for pT &gt; 2 GeV/$c$. The observed enhancement at negative rapidity has implications for the observed modification in heavy-ion collisions at high $p_T$.
DOI: 10.17182/hepdata.142077.v1/t10
title: "Figure 7a-3" of "Transverse-Momentum Dependence of the J/psi Nuclear Modification in d+Au Collisions at sqrt(s_NN)=200 GeV"

description: $J/\psi$ invariant yield as a function of $p_T$ for each centrality for −2.2 &lt; $y$ &lt; −1.2. The type C systematic uncertainty for each distribution is given as a percentage in the legend. Type A represents uncertainties that are uncorrelated from point to point, Type B represents uncertainties that are correlated from point to point, and Type C represents uncertainties in the overall normalization.
description: We present measured $J/\psi$ production rates in $d$+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV over a broad range of transverse momentum ($p_T$ = 0–14 GeV/$c$) and rapidity (−2.2 &lt; y &lt; 2.2). We construct the nuclear-modification factor $R_{dAu}$ for these kinematics and as a function of collision centrality (related to impact parameter for the $R_{dAu}$ collision). We find that the modification is largest for collisions with small impact parameters, and observe a suppression ($R_{dAu}$ &lt; 1) for $p_T$ &lt; 4 GeV/$c$ at positive rapidities. At negative rapidity we observe a suppression for $p_T$ &lt; 2 GeV/$c$ then an enhancement ($R_{dAu}$ &gt; 1) for pT &gt; 2 GeV/$c$. The observed enhancement at negative rapidity has implications for the observed modification in heavy-ion collisions at high $p_T$.
DOI: 10.17182/hepdata.142077.v1/t11
title: "Figure 7a-4" of "Transverse-Momentum Dependence of the J/psi Nuclear Modification in d+Au Collisions at sqrt(s_NN)=200 GeV"

description: $J/\psi$ invariant yield as a function of $p_T$ for each centrality for −2.2 &lt; $y$ &lt; −1.2. The type C systematic uncertainty for each distribution is given as a percentage in the legend. Type A represents uncertainties that are uncorrelated from point to point, Type B represents uncertainties that are correlated from point to point, and Type C represents uncertainties in the overall normalization.
description: We present measured $J/\psi$ production rates in $d$+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV over a broad range of transverse momentum ($p_T$ = 0–14 GeV/$c$) and rapidity (−2.2 &lt; y &lt; 2.2). We construct the nuclear-modification factor $R_{dAu}$ for these kinematics and as a function of collision centrality (related to impact parameter for the $R_{dAu}$ collision). We find that the modification is largest for collisions with small impact parameters, and observe a suppression ($R_{dAu}$ &lt; 1) for $p_T$ &lt; 4 GeV/$c$ at positive rapidities. At negative rapidity we observe a suppression for $p_T$ &lt; 2 GeV/$c$ then an enhancement ($R_{dAu}$ &gt; 1) for pT &gt; 2 GeV/$c$. The observed enhancement at negative rapidity has implications for the observed modification in heavy-ion collisions at high $p_T$.
DOI: 10.17182/hepdata.142077.v1/t6
title: "Figure 5-3" of "Transverse-Momentum Dependence of the J/psi Nuclear Modification in d+Au Collisions at sqrt(s_NN)=200 GeV"

description: $J/\psi$ invariant yield as a function of $p_T$ for each centrality at $|y|$ &lt; 0.35. The type C systematic uncertainty for each distribution is given as a percentage in the legend. Type A represents uncertainties that are uncorrelated from point to point, Type B represents uncertainties that are correlated from point to point, and Type C represents uncertainties in the overall normalization.
description: We present measured $J/\psi$ production rates in $d$+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV over a broad range of transverse momentum ($p_T$ = 0–14 GeV/$c$) and rapidity (−2.2 &lt; y &lt; 2.2). We construct the nuclear-modification factor $R_{dAu}$ for these kinematics and as a function of collision centrality (related to impact parameter for the $R_{dAu}$ collision). We find that the modification is largest for collisions with small impact parameters, and observe a suppression ($R_{dAu}$ &lt; 1) for $p_T$ &lt; 4 GeV/$c$ at positive rapidities. At negative rapidity we observe a suppression for $p_T$ &lt; 2 GeV/$c$ then an enhancement ($R_{dAu}$ &gt; 1) for pT &gt; 2 GeV/$c$. The observed enhancement at negative rapidity has implications for the observed modification in heavy-ion collisions at high $p_T$.
DOI: 10.17182/hepdata.142077.v1/t7
title: "Figure 5-4" of "Transverse-Momentum Dependence of the J/psi Nuclear Modification in d+Au Collisions at sqrt(s_NN)=200 GeV"

description: $J/\psi$ invariant yield as a function of $p_T$ for each centrality at $|y|$ &lt; 0.35. The type C systematic uncertainty for each distribution is given as a percentage in the legend. Type A represents uncertainties that are uncorrelated from point to point, Type B represents uncertainties that are correlated from point to point, and Type C represents uncertainties in the overall normalization.
description: We present measured $J/\psi$ production rates in $d$+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV over a broad range of transverse momentum ($p_T$ = 0–14 GeV/$c$) and rapidity (−2.2 &lt; y &lt; 2.2). We construct the nuclear-modification factor $R_{dAu}$ for these kinematics and as a function of collision centrality (related to impact parameter for the $R_{dAu}$ collision). We find that the modification is largest for collisions with small impact parameters, and observe a suppression ($R_{dAu}$ &lt; 1) for $p_T$ &lt; 4 GeV/$c$ at positive rapidities. At negative rapidity we observe a suppression for $p_T$ &lt; 2 GeV/$c$ then an enhancement ($R_{dAu}$ &gt; 1) for pT &gt; 2 GeV/$c$. The observed enhancement at negative rapidity has implications for the observed modification in heavy-ion collisions at high $p_T$.
DOI: 10.17182/hepdata.142077.v1/t8
title: "Figure 7a-1" of "Transverse-Momentum Dependence of the J/psi Nuclear Modification in d+Au Collisions at sqrt(s_NN)=200 GeV"

description: $J/\psi$ invariant yield as a function of $p_T$ for each centrality for −2.2 &lt; $y$ &lt; −1.2. The type C systematic uncertainty for each distribution is given as a percentage in the legend. Type A represents uncertainties that are uncorrelated from point to point, Type B represents uncertainties that are correlated from point to point, and Type C represents uncertainties in the overall normalization.
description: We present measured $J/\psi$ production rates in $d$+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV over a broad range of transverse momentum ($p_T$ = 0–14 GeV/$c$) and rapidity (−2.2 &lt; y &lt; 2.2). We construct the nuclear-modification factor $R_{dAu}$ for these kinematics and as a function of collision centrality (related to impact parameter for the $R_{dAu}$ collision). We find that the modification is largest for collisions with small impact parameters, and observe a suppression ($R_{dAu}$ &lt; 1) for $p_T$ &lt; 4 GeV/$c$ at positive rapidities. At negative rapidity we observe a suppression for $p_T$ &lt; 2 GeV/$c$ then an enhancement ($R_{dAu}$ &gt; 1) for pT &gt; 2 GeV/$c$. The observed enhancement at negative rapidity has implications for the observed modification in heavy-ion collisions at high $p_T$.