Rapidity and centrality dependence of particle production for identified hadrons in Cu+Cu collisions at $\sqrt{s_{NN}} = 200$ GeV

The BRAHMS collaboration Arsene, I.C. ; Bearden, I.G. ; Beavis, D. ; et al.
Phys.Rev.C 94 (2016) 014907, 2016.
Inspire Record 1419279 DOI 10.17182/hepdata.89453

The BRAHMS collaboration has measured transverse momentum spectra of pions, kaons, protons and antiprotons at rapidities 0 and 3 for Cu+Cu collisions at $\sqrt{s_{NN}} = 200$ GeV. As the collisions become more central the collective radial flow increases while the temperature of kinetic freeze-out decreases. The temperature is lower and the radial flow weaker at forward rapidity. Pion and kaon yields with transverse momenta between 1.5 and 2.5 GeV/c are suppressed for central collisions relative to scaled $p+p$ collisions. This suppression, which increases as the collisions become more central is consistent with jet quenching models and is also present with comparable magnitude at forward rapidity. At such rapidities initial state effects may also be present and persistence of the meson suppression to high rapidity may reflect a combination of jet quenching and nuclear shadowing. The ratio of protons to mesons increases as the collisions become more central and is largest at forward rapidities.

138 data tables

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$, $m_{\mathrm{T}}-m_{0}$ versus $p_{\mathrm{T}}$ for $\mathrm{K}^{-}$ in $\mathrm{Cu}-\mathrm{Cu}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$, $m_{\mathrm{T}}-m_{0}$ versus $p_{\mathrm{T}}$ for $\mathrm{K}^{-}$ in $\mathrm{Cu}-\mathrm{Cu}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$, $m_{\mathrm{T}}-m_{0}$ versus $p_{\mathrm{T}}$ for $\mathrm{K}^{-}$ in $\mathrm{Cu}-\mathrm{Cu}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$

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Rapidity dependence of deuteron production in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV

The BRAHMS collaboration Arsene, I. ; Bearden, I.G. ; Beavis, D. ; et al.
Phys.Rev.C 83 (2011) 044906, 2011.
Inspire Record 856692 DOI 10.17182/hepdata.89452

We have measured the distributions of protons and deuterons produced in high energy heavy ion Au+Au collisions at RHIC over a very wide range of transverse and longitudinal momentum. Near mid-rapidity we have also measured the distribution of anti-protons and anti-deuterons. We present our results in the context of coalescence models. In particular we extract the "volume of homogeneity" and the average phase-space density for protons and anti-protons. Near central rapidity the coalescence parameter $B_2(p_T)$ and the space averaged phase-space density $<f> (p_T)$ are very similar for both protons and anti-protons. For protons we see little variation of either $B_2(p_T)$ or the space averaged phase-space density as the rapidity increases from 0 to 3. However both these quantities depend strongly on $p_T$ at all rapidities. These results are in contrast to lower energy data where the proton and anti-proton phase-space densities are different at $y$=0 and both $B_2$ and $f$ depend strongly on rapidity.

25 data tables

$C_{\Lambda}(p_{\mathrm{T}})$ versus $p_{\mathrm{T}}$ for $\mathrm{\Lambda}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$ near $y=[0, 1, 2, 3]$ for $0-20$% central

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$ versus $p_{\mathrm{T}}$ for $\mathrm{p}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$ near $y=0$ for $0-20$% central

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$ versus $p_{\mathrm{T}}$ for $\mathrm{d}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$ near $y=0$ for $0-20$% central

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Kaon and Pion Production in Central Au+Au Collisions at \sqrt{s_{NN}}=62.4 GeV

The BRAHMS collaboration Arsene, I.C. ; Bearden, I.G. ; Beavis, D. ; et al.
Phys.Lett.B 687 (2010) 36-41, 2010.
Inspire Record 836865 DOI 10.17182/hepdata.89451

Invariant pT spectra and rapidity densities covering a large rapidity range(-0.1 < y < 3.5) are presented for $\pi^{\pm}$ and $K^{\pm}$ mesons from central Au+Au collisions at $\sqrt{s_{NN}}$ = 62.4 GeV. The mid-rapidity yields of meson particles relative to their anti-particles are found to be close to unity ($\pi^-/\pi^+ \sim 1$, $K^-/K^+ \sim 0.85$) while the anti-proton to proton ratio is $\bar{p}/p \sim 0.49$. The rapidity dependence of the $\pi^-/\pi^+$ ratio is consistent with a small increase towards forward rapidities while the $K^-/K^+$ and $\bar{p}/p$ ratios show a steep decrease to $\sim$ 0.3 for kaons and 0.022 for protons at $y\sim 3$. It is observed that the kaon production relative to its own anti-particle as well as to pion production in wide rapidity and energy ranges shows an apparent universal behavior consistent with the baryo-chemical potential, as deduced from the $\bar{p}/p$ ratio, being the driving parameter.

40 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 $\mathrm{\pi}^{+}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=62.4\,\mathrm{Ge\!V}$ near $y=-0.2-0.0$ for $0-10$% central

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$ versus $p_{\mathrm{T}}$ for $\mathrm{\pi}^{+}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=62.4\,\mathrm{Ge\!V}$ near $y=0.0-0.2$ for $0-10$% central

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$ versus $p_{\mathrm{T}}$ for $\mathrm{\pi}^{+}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=62.4\,\mathrm{Ge\!V}$ near $y=0.7-0.9$ for $0-10$% central

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Nuclear stopping and rapidity loss in Au+Au collisions at sqrt{s_{NN}}=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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Nuclear modification factor for charged pions and protons at forward rapidity in central Au + Au collisions at 200-GeV.

The BRAHMS collaboration Arsene, I. ; Bearden, I.G. ; Beavis, D. ; et al.
Phys.Lett.B 650 (2007) 219-223, 2007.
Inspire Record 729167 DOI 10.17182/hepdata.89447

We present spectra of charged pions and protons in 0-10% central Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV at mid-rapidity ($y=0$) and forward pseudorapidity ($\eta=2.2$) measured with the BRAHMS experiment at RHIC. The spectra are compared to spectra from p+p collisions at the same energy scaled by the number of binary collisions. The resulting nuclear modification factors for central Au+Au collisions at both $y=0$ and $\eta=2.2$ exhibit suppression for charged pions but not for (anti-)protons at intermediate $p_T$. The $\bar{p}/\pi^-$ ratios have been measured up to $p_T\sim 3$ GeV/$c$ at the two rapidities and the results indicate that a significant fraction of the charged hadrons produced at intermediate $p_T$ range are (anti-)protons at both mid-rapidity and $\eta = 2.2$.

17 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 $\overline{\mathrm{p}}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$ versus $p_{\mathrm{T}}$ for $\mathrm{\pi}^{-}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$ versus $p_{\mathrm{T}}$ for $\mathrm{p}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$

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Centrality dependent particle production at y = 0 and y approx. 1 in Au + Au collisions at s(NN)**(1/2) = 200-GeV.

The BRAHMS collaboration Arsene, I. ; Bearden, I.G. ; Beavis, D. ; et al.
Phys.Rev.C 72 (2005) 014908, 2005.
Inspire Record 678407 DOI 10.17182/hepdata.89446

Particle production of identified charged hadrons, $\pi^{\pm}$, $K^{\pm}$, $p$, and $\bar{p}$ in Au+Au collisions at $\sqrt(snn) =$ 200 GeV has been studied as a function of transverse momentum and collision centrality at $y=0$ and $y\sim1$ by the BRAHMS experiment at RHIC. Significant collective transverse flow at kinetic freeze-out has been observed in the collisions. The magnitude of the flow rises with the collision centrality. Proton and kaon yields relative to the pion production increase strongly as the transverse momentum increases and also increase with centrality. Particle yields per participant nucleon show a weak dependence on the centrality for all particle species. Hadron production remains relatively constant within one unit around midrapidity in Au+Au collisions at $\sqrt(snn) =$ 200 GeV.

13 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 $\mathrm{\pi}^{+}$,$\mathrm{\pi}^{-}$,$\mathrm{K}^{+}$,$\mathrm{K}^{-}$,$\mathrm{p}$,$\overline{\mathrm{p}}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$

$\langle p_{\mathrm{T}}\rangle$ versus $N_{\mathrm{part}}$ for $\mathrm{\pi}^{+}$,$\mathrm{\pi}^{-}$,$\mathrm{K}^{+}$,$\mathrm{K}^{-}$,$\mathrm{p}$,$\overline{\mathrm{p}}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$

$\beta_{\mathrm{S}}$,$T$,$\chi^2$,$\nu$ versus $\mathrm{Centrality}$ for $\mathrm{h}^{+}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$

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On the evolution of the nuclear modification factors with rapidity and centrality in d + Au collisions at s(NN)**(1/2) = 200-GeV.

The BRAHMS collaboration Arsene, I. ; Bearden, I.G. ; Beavis, D. ; et al.
Phys.Rev.Lett. 93 (2004) 242303, 2004.
Inspire Record 645789 DOI 10.17182/hepdata.89444

We report on a study of the transverse momentum dependence of nuclear modification factors $R_{dAu}$ for charged hadrons produced in deuteron + gold collisions at $\sqrt{s_{NN}=\unit[200]{GeV}$, as a function of collision centrality and of the pseudorapidity ($\eta = 0,1,2.2,3.2 $) of the produced hadrons. We find significant and systematic decrease of $R_{dAu}$ with increasing rapidity. The midrapidity enhancement and the forward rapidity suppression are more pronounced in central collisions relative to peripheral collisions. These results are relevant to the study of the possible onset of gluon saturation at RHIC energies.

9 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 $\frac{h^{+}+h^{-}}{2}$,$\frac{h^{+}+h^{-}}{2}$ in $\mathrm{p}\mathrm{p}$,$\mathrm{d}-\mathrm{Au}$ at $\sqrt{s}=200\,\mathrm{Ge\!V}$ near $\eta=0$

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$ versus $p_{\mathrm{T}}$ for $\frac{h^{+}+h^{-}}{2}$,$\frac{h^{+}+h^{-}}{2}$ in $\mathrm{p}\mathrm{p}$,$\mathrm{d}-\mathrm{Au}$ at $\sqrt{s}=200\,\mathrm{Ge\!V}$ near $\eta=1$

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$ versus $p_{\mathrm{T}}$ for $\mathrm{h}^{-}$,$\mathrm{h}^{-}$ in $\mathrm{p}\mathrm{p}$,$\mathrm{d}-\mathrm{Au}$ at $\sqrt{s}=200\,\mathrm{Ge\!V}$ near $\eta=2.2$

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Charged meson rapidity distributions in central Au + Au collisions at s(NN)**(1/2) = 200-GeV.

The BRAHMS collaboration Bearden, I.G. ; Beavis, D. ; Besliu, C. ; et al.
Phys.Rev.Lett. 94 (2005) 162301, 2005.
Inspire Record 647076 DOI 10.17182/hepdata.89445

We have measured rapidity densities dN/dy of pions and kaons over a broad rapidity range (-0.1 < y < 3.5) for central Au+Au collisions at sqrt(snn) = 200 GeV. These data have significant implications for the chemistry and dynamics of the dense system that is initially created in the collisions. The full phase-space yields are 1660 +/- 15 +/- 133 (pi+), 1683 +/- 16 +/- 135 (pi-), 286 +/- 5 +/- 23 (K+) and 242 +/- 4 +/- 19 (K-). The systematics of the strange to non--strange meson ratios are found to track the variation of the baryo-chemical potential with rapidity and energy. Landau--Carruthers hydrodynamic is found to describe the bulk transport of the pions in the longitudinal direction.

60 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 $\mathrm{\pi}^{+}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$ near $y=-0.1-0.0$ for $0-5$% central

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$ versus $p_{\mathrm{T}}$ for $\mathrm{\pi}^{+}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$ near $y=0.0-0.1$ for $0-5$% central

$\frac{1}{2\pi p_{\mathrm{T}}}\frac{\mathrm{d}^2N}{\mathrm{d}p_{\mathrm{T}}\mathrm{d}y}$ versus $p_{\mathrm{T}}$ for $\mathrm{\pi}^{+}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$ near $y=0.4-0.6$ for $0-5$% central

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Nuclear stopping in Au + Au collisions at s(NN)**(1/2) = 200-GeV.

The BRAHMS collaboration Bearden, I.G. ; Beavis, D. ; Besliu, C. ; et al.
Phys.Rev.Lett. 93 (2004) 102301, 2004.
Inspire Record 636579 DOI 10.17182/hepdata.89443

Transverse momentum spectra and rapidity densities, dN/dy, of protons, anti-protons, and net--protons (p-pbar) from central (0-5%) Au+Au collisions at sqrt(sNN) = 200 GeV were measured with the BRAHMS experiment within the rapidity range 0 < y < 3. The proton and anti-proton dN/dy decrease from mid-rapidity to y=3. The net-proton yield is roughly constant for y<1 at dN/dy~7, and increases to dN/dy~12 at y~3. The data show that collisions at this energy exhibit a high degree of transparency and that the linear scaling of rapidity loss with rapidity observed at lower energies is broken. The energy loss per participant nucleon is estimated to be 73 +- 6 GeV.

2 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 $\mathrm{p}$,$\overline{\mathrm{p}}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$ . NaN values means no observation.

$\frac{\mathrm{d}N}{\mathrm{d}y}$ versus $y$ for $\mathrm{p}$,$\overline{\mathrm{p}}$,$\mathrm{p}-\overline{\mathrm{p}}$ in $\mathrm{Au}-\mathrm{Au}$ at $\sqrt{s_{\mathrm{NN}}}=200\,\mathrm{Ge\!V}$ . The correction for the $\Lambda$ contribution is not straight forward since BRAHMS does not measure the $\Lambda$s and PHENIX and STAR only measures the $\Lambda$s at mid-rapidity! If one assumes that the mid-rapidity estimated in the paper of $$R=\frac{\Lambda-\bar{\Lambda}}{\mathrm{p}-\bar{\mathrm{p}}} = \frac{\Lambda}{\mathrm{p}} = \frac{\bar{\Lambda}}{\bar{\mathrm{p}}} = 0.93\pm 0.11(\mathrm{stat})\pm 0.25(\mathrm{syst}) $$ and the BRAHMS "acceptance factor" of $A=0.53\pm 0.05$ which includes both that only 64% decays to protons and that some are rejected by the requirement of the track to point back to the IP. The corrected $\mathrm{p}$ ($\bar{\mathrm{p}}$ or net-$\mathrm{p}$) is then : $$\left.\frac{\mathrm{d}N}{\mathrm{d}y}\right|_{\mathrm{corrected}} = \frac{\mathrm{d}N}{\mathrm{d}y}(1/(1+RA))= \frac{\mathrm{d}N}{\mathrm{d}y}\left(0.67\pm 0.05(\mathrm{stat})\pm 0.11(\mathrm{syst})\right)$$ Which can be used at all rapidities if one believes that R is constant. The fact that net-$\mathrm{K}=\mathrm{K}^{+}-\mathrm{K}^{-}$ follows net-$\mathrm{p}$ (see fx. talk by Djamel Ouerdane at QM04), seems to indicate that the net-$\Lambda$ follow the net-$\mathrm{p}$ trend and the correction is reasonable.