Elliptic flow versus $p_{T}$ for charged hadrons from Cu+Cu collisions at 0–60% centrality at $\sqrt{s_{NN}}$ = 22.4 GeV measured with the subevent method with a pseudorapidity gap of 0.3 units compared with previously published STAR results for 200 and 62.4 GeV Cu+Cu [27] measured with full TPC event plane method $v_{2}${TPC} and full FTPC event plane method $v_{2}${FTPC}. The error bars are statistical. Results are also compared to $v_{2}$($p_{T}$) model calculations.

Elliptic flow $v_{2}(\eta)$ for charged hadrons fromCu+Cu collisions at 0–60% centrality at $\sqrt{s_{NN}}$ = 22.4 GeV. The present STAR results are compared to the measurement from the PHOBOS [29] collaboration for Cu+Cu at 22.4 GeV. The PHOBOS results include statistical and systematic errors whereas the STAR results are plotted with statistical uncertainties only, and systematic errors are discussed in Section III C. Results are also compared to $v_{2}(\eta)$ calculations from the indicated models.

Elliptic flow $v_{2}${TPC} and $v_{2}${4} as a function of centrality for charged hadrons from Cu+Cu collisions at 0 − 60% centrality at $\sqrt{s_{NN}}$ = 22.4 GeV, compared with previously published results from the STAR collaboration at 200 GeV and 62.4 GeV.

$\Omega + \bar{\Omega}$ invariant mass spectra from Cu+Cu $\sqrt{s_{NN}} = 200$ GeV collisions, where $|y| < 0.5$. The uncertainties on the spectra points are statistical and systematic combined.

$K^0_S$ invariant mass spectra from Au+Au $\sqrt{s_{NN}} = 200$ GeV collisions, where $|y| < 0.5$. The uncertainties on the spectra points are statistical and systematic combined.

$\Lambda$ and $\bar{\Lambda}$ invariant mass spectra from Au+Au $\sqrt{s_{NN}} = 200$ GeV collisions, where $|y| < 0.5$. The $\Lambda$ and $\bar{\Lambda}$ yields have not been feed down subtracted from weak decays. The uncertainties on the spectra points are statistical and systematic combined.

$K^0_S$, $\Lambda$, and $\bar{\Lambda}$, spectra divided by $\langle N_{part} \rangle$ for Cu+Cu $0 − 10\%$ ($\langle N_{part} \rangle \sim 99$) and Au+Au $20 − 40\%$ ($\langle N_{part} \rangle \sim 141$) $\sqrt{s_{NN}} = 200$ GeV collisions, where $|y| < 0.5$. The $\Lambda$ and $\bar{\Lambda}$ yields have been feed down subtracted from weak decays. The uncertainties on the spectra points are statistical and systematic; for clarity the uncertainty on $\langle N_{part} \rangle$ has not been included. The curves show the functions described in the text used to extract $dN/dy$.

$\Xi + \bar{\Xi}$ spectra divided by $\langle N_{part} \rangle$ for Cu+Cu $0 − 10\%$ ($\langle N_{part} \rangle \sim 99$) $\sqrt{s_{NN}} = 200$ GeV collisions, where $|y| < 0.5$. The uncertainties on the spectra points are statistical and systematic; for clarity the uncertainty on $\langle N_{part} \rangle$ has not been included. The curves show the functions described in the text used to extract $dN/dy$.

$\Xi + \bar{\Xi}$ spectra divided by $\langle N_{part} \rangle$ for Au+Au $20 − 40\%$ ($\langle N_{part} \rangle \sim 141$) $\sqrt{s_{NN}} = 200$ GeV collisions, where $|y| < 0.5$. The uncertainties on the spectra points are statistical and systematic; for clarity the uncertainty on $\langle N_{part} \rangle$ has not been included. The curves show the functions described in the text used to extract $dN/dy$.

$\Omega + \bar{\Omega}$ spectra divided by $\langle N_{part} \rangle$ for Cu+Cu $0 − 10\%$ ($\langle N_{part} \rangle \sim 99$) $\sqrt{s_{NN}} = 200$ GeV collisions, where $|y| < 0.5$. The uncertainties on the spectra points are statistical and systematic; for clarity the uncertainty on $\langle N_{part} \rangle$ has not been included. The curves show the functions described in the text used to extract $dN/dy$.

$\Omega + \bar{\Omega}$ spectra divided by $\langle N_{part} \rangle$ for Au+Au $20 − 40\%$ ($\langle N_{part} \rangle \sim 141$) $\sqrt{s_{NN}} = 200$ GeV collisions, where $|y| < 0.5$. The uncertainties on the spectra points are statistical and systematic; for clarity the uncertainty on $\langle N_{part} \rangle$ has not been included. The curves show the functions described in the text used to extract $dN/dy$.

The enhancement factor for (multi-) strange particles in Cu+Cu $\sqrt{s_{NN}} = 200$ GeV collisions, where $|y| < 0.5$. The $\Lambda$, and $\bar{\Lambda}$ yields have been feed-down subtracted in all cases. The black bars show the normalization uncertainties, and the uncertainties for the heavy-ion points are the combined statistical and systematic errors. Curves described in the text, where $B_{K} = 2.0$, $B_{\Lambda} = 2.4$, $B_{\Xi} = 5.0$ and $B_{\Omega} = 12.1$.

The enhancement factor for (multi-) strange particles in Au+Au $\sqrt{s_{NN}} = 200$ GeV collisions, where $|y| < 0.5$. The $\Lambda$, and $\bar{\Lambda}$ yields have been feed-down subtracted in all cases. The black bars show the normalization uncertainties, and the uncertainties for the heavy-ion points are the combined statistical and systematic errors. Curves described in the text, where $B_{K} = 2.0$, $B_{\Lambda} = 2.4$, $B_{\Xi} = 5.0$ and $B_{\Omega} = 12.1$.

Ratio of particle yields in central Cu+Cu and midcentral Au+Au collisions when $\langle N_{part} \rangle = 99$ in each case for $|y| < 0.5$. $\pi$ yields are from elsewhere [17]. Boxed uncertainties are from the Glauber calculations and are correlated for every particle. $\langle N_{part>1} \rangle$ refers to the parameterization shown by eq. 1, while the EPOS and AMPT models are described in the text. The default settings are used for each model. The vertical lines show the remaining independent statistical and systematic uncertainties.

$\rho^0$ production cross section determined with the data set collected with trigger B, as a function of momentum transfer $t$, fitted with a double exponential fit function in the range $t < 0.1$. The statistical errors are shown. The ratio of incoherent to coherent cross sections is measured to be $0.20 \pm 0.8$. The fit parameters are shown in Table I.

Comparison of theoretical predictions to the measured total cross section for coherent $\rho^0$ production as a functionof $\sqrt{s_{NN}}$ . The measured cross section is based on the dataset collected with trigger B. The error bars show the sum of the statistical and systematic uncertainties. See text for details.

The correlation function C, C is plotted in units of (GeV/c)$^2$ and the relative azimuthal angle ∆φ in radians for 30-40% centrality in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. Relative statistical errors range from 0.8% in peripheral collisions to 0.9% in the most central collisions at the peak of the distribution.

The correlation function C, C is plotted in units of (GeV/c)$^2$ and the relative azimuthal angle ∆φ in radians for 0-5% centrality in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV..Relative statistical errors range from 0.8% in peripheral collisions to 0.9% in the most central collisions at the peak of the distribution.

The correlation function C, C is plotted in units of (GeV/c)$^2$ and the relative azimuthal angle ∆φ in radians for 0-5% centrality in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV..Relative statistical errors range from 0.8% in peripheral collisions to 0.9% in the most central collisions at the peak of the distribution.

Projection of the correlation function C, for|∆φ|<1.0 radians on the ∆η axis for 70-80% centrality in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. The correlation function C is plottedin units of (GeV/c)$^2$.The correlation function C is plotted in units of (GeV/c)$^2$. The solid line shows the fit obtained with Eq.2. The dotted line corresponds to the baseline, b, obtained in the fit and shaded band shows uncertainty in determining b.

Projection of the correlation function C, for|∆φ|<1.0 radians on the ∆η axis for 70-80% centrality in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. The correlation function C is plottedin units of (GeV/c)$^2$.The correlation function C is plotted in units of (GeV/c)$^2$. The solid line shows the fit obtained with Eq.2. The dotted line corresponds to the baseline, b, obtained in the fit and shaded band shows uncertainty in determining b.

Projection of the correlation function C, for|∆φ|<1.0 radians on the ∆η axis for 30-40% centrality. Statistical errors at(\Deltaeta_1,Deltaeta_2~(0,0) are approximately 0.084 for Au+Au. The correlation function C is plotted in units of (GeV/c)$^2$. The dotted line corresponds to the baseline,b, obtained in the fit and shaded band shows uncertainty in determining b.

Projection of the correlation function C, for|∆φ|<1.0 radians on the ∆η axis for 30-40% centrality. Statistical errors at(\Deltaeta_1,Deltaeta_2~(0,0) are approximately 0.084 for Au+Au. The correlation function C is plotted in units of (GeV/c)$^2$. The dotted line corresponds to the baseline,b, obtained in the fit and shaded band shows uncertainty in determining b.

Projection of the correlation function C, for|∆φ|<1.0 radians on the ∆η axis for 0-5% centrality in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. The correlation functionCis plotted in units of (GeV/c)$^2$. The correlation function C is plotted in units of (GeV/c)$^2$. The solid line shows the fit obtained with Eq.2. The dotted line corresponds to the baseline,b, obtained in the fit and shaded band shows uncertainty in determining b.

Projection of the correlation function C, for|∆φ|<1.0 radians on the ∆η axis for 0-5% centrality in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. The correlation functionCis plotted in units of (GeV/c)$^2$. The correlation function C is plotted in units of (GeV/c)$^2$. The solid line shows the fit obtained with Eq.2. The dotted line corresponds to the baseline,b, obtained in the fit and shaded band shows uncertainty in determining b.

RMS as function of the number of participating nucleons for the correlation function C, for nine centrality classes in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. The dotted line represents a lower limit estimate of the RMS explained in the text and the shaded band represents systematic uncertainties on the RMS.

RMS as function of the number of participating nucleons for the correlation function C, for nine centrality classes in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. The dotted line represents a lower limit estimate of the RMS explained in the text and the shaded band represents systematic uncertainties on the RMS.