The expected 95% CL exclusion contour (-1$\sigma$) for a simplified model of dark-matter production involving an axial-vector operator, Dirac DM and couplings $g_{q}$ = 0.25, $g_{\chi}$ = 1 and $g_{l}$ = 0 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.

The expected 95% CL exclusion contour for a simplified model of dark-matter production involving an axial-vector operator, Dirac DM and couplings $g_{q}$ = 0.25, $g_{\chi}$ = 1 and $g_{l}$ = 0 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.

The observed 95% CL exclusion contour for a simplified model of dark-matter production involving an axial-vector operator, Dirac DM and couplings $g_{q}$ = 0.1, $g_{\chi}$ = 1 and $g_{l}$ = 0.1 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.

The expected 95% CL exclusion contour (+1$\sigma$) for a simplified model of dark-matter production involving an axial-vector operator, Dirac DM and couplings $g_{q}$ = 0.1, $g_{\chi}$ = 1 and $g_{l}$ = 0.1 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.

The expected 95% CL exclusion contour (-1$\sigma$) for a simplified model of dark-matter production involving an axial-vector operator, Dirac DM and couplings $g_{q}$ = 0.1, $g_{\chi}$ = 1 and $g_{l}$ = 0.1 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.

The expected 95% CL exclusion contour for a simplified model of dark-matter production involving an axial-vector operator, Dirac DM and couplings $g_{q}$ = 0.1, $g_{\chi}$ = 1 and $g_{l}$ = 0.1 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.

The observed 95% CL exclusion contour for a simplified model of dark-matter production involving a vector operator with couplings $g_{q}$ = 0.25, $g_{\chi}$ =1 and $g_{l}$ = 0 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.

The expected 95% CL exclusion contour ($+1\sigma$) for a simplified model of dark-matter production involving a vector operator with couplings $g_{q}$ = 0.25, $g_{\chi}$ =1 and $g_{l}$ = 0 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.

The expected 95% CL exclusion contour ($-1\sigma$) for a simplified model of dark-matter production involving a vector operator with couplings $g_{q}$ = 0.25, $g_{\chi}$ =1 and $g_{l}$ = 0 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.

The expected 95% CL exclusion contour for a simplified model of dark-matter production involving a vector operator with couplings $g_{q}$ = 0.25, $g_{\chi}$ =1 and $g_{l}$ = 0 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.

The observed 95% CL exclusion contour for a simplified model of dark-matter production involving for a vector operator with couplings $g_{q}$ = 0.1, $g_{\chi}$ = 1 and $g_{l}$ = 0.01 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.

The expected 95% CL exclusion contour ($+1\sigma$) for a simplified model of dark-matter production involving for a vector operator with couplings $g_{q}$ = 0.1, $g_{\chi}$ = 1 and $g_{l}$ = 0.01 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.

The expected 95% CL exclusion contour ($-1\sigma$) for a simplified model of dark-matter production involving for a vector operator with couplings $g_{q}$ = 0.1, $g_{\chi}$ = 1 and $g_{l}$ = 0.01 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.

The expected 95% CL exclusion contour for a simplified model of dark-matter production involving for a vector operator with couplings $g_{q}$ = 0.1, $g_{\chi}$ = 1 and $g_{l}$ = 0.01 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.

The 90% CL exclusion limit on the $\chi$-proton scattering cross section in a simplifed model of dark-matter production involving an axial-vector operator, Dirac DM and couplings $g_{q}$ = 0.25, $g_{\chi}$ = 1 and $g_{l}$ = 0 as a function of the dark-matter mass $m_{\chi}$.

The 90% CL exclusion limit on the $\chi$-nucleon scattering cross section in a simplifed model of dark-matter production involving a vector operator, Dirac DM and couplings $g_{q}$ = 0.25, $g_{\chi}$ = 1 and $g_{l}$ = 0 as a function of the dark-matter mass $m_{\chi}$.

The observed and expected 95% CL limits on M* for a dimension-7 operator EFT model with a contact interaction of type $\gamma\gamma\chi\chi$ as a function of dark-matter mass $m_{\chi}$.

The observed and expected limit at 95% CL on the production cross section of a $Z\gamma$ resonance as a function of its mass.

The observed 95% CL upper limits on signal strength $\mu$, the ratio of the experimental limit to the predicted signal cross section, for a simplified model of dark matter production involving an axial-vector operator, Dirac DM and couplings $g_{q}$ = 0.25 and $g_{\chi}$ = 1 as a function of the DM and the mediator particle masses. The bound on $\mu$ only applies for choices of couplings that yield the same kinematic distributions as the benchmark model.

Acceptance, in %, for a simplified model of dark matter production involving an axial-vector operator, Dirac DM and couplings $g_{q}$= 0.25 and $g_{\chi}$ = 1 for various $m_{\chi}$ and $m_{\textrm{med}}$ values. It is constant as a function of $m_{\chi}$ for a fixed $m_{\textrm{med}}$ in the region $m_{\textrm{med}}>2m_{\chi}$.

Fiducial reconstruction efficiencies in the three inclusive signal regions for a simplified model of dark matter production involving an axial-vector operator, Dirac DM and couplings $g_{q}$= 0.25 and $g_{\chi}$ = 1 for various $m_{\chi}$ and $m_{\textrm{med}}$ values. It is constant as a function of $m_{\chi}$ for a fixed $m_{\textrm{med}}$ in the region $m_{\textrm{med}}>2m_{\chi}$.

(Color online) Global polarization of $\Lambda$–hyperons as a function of centrality given as fraction of the total inelastic hadronic cross section. 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 $\overline{\Lambda}$–hyperons as a function of $\overline{\Lambda}$ transverse momentum $p^{\overline{\Lambda}}_{t}$. 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 $\overline{\Lambda}$–hyperons as a function of $\overline{\Lambda}$ pseudorapidity $\eta^{\overline{\Lambda}}$. 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 $P_{\Lambda}=(1.8\pm 10.8)\times 10^{-3}$ with $\chi^{2}/ndf=5.5/10$. Open squares show the results for Au+Au collisions as $\sqrt{s_{NN}}$=62.4 GeV (centrality region 0-80%). A constant line fit gives $P_{\Lambda}=(-17.6\pm 11.1)\times 10^{-3}$ with $\chi^{2}/ndf=8.0/10$. Only statistical uncertainties are shown.

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

(Color online) Acceptance correction function $A_{0}(p^{H}_{t}, \eta^{H})$ defined in (10) as a function of $\Lambda$ (filled circles) and $\overline{\Lambda}$ (open squares) transverse momentum (top) and pseudorapidity (bottom). The deviation of this function from unity affects the overall scale of the measured global polarization according to Eq. 9. See the text for details and discussions on $A_{0}$ $p^{H}_{t}$ and $\eta^{H}$ dependence.

(Color online) Acceptance correction function $A_{0}(p^{H}_{t}, \eta^{H})$ defined in (10) as a function of $\Lambda$ (filled circles) and $\overline{\Lambda}$ (open squares) transverse momentum (top) and pseudorapidity (bottom). The deviation of this function from unity affects the overall scale of the measured global polarization according to Eq. 9. See the text for details and discussions on $A_{0}$ $p^{H}_{t}$ and $\eta^{H}$ dependence.

(Color online) Function $A_{2}(p^{H}_{t}, \eta^{H})$ defined in (11) as a function of $\Lambda$ (filled circles) and $\overline{\Lambda}$ (open squares) transverse momentum (top) and pseudorapidity (bottom). The deviation of this function from zero defines the contribution to the observable (3) from $P^{(2)}_{H} (p^{H}_{t}, \eta^{H})$ in the expansion (6).

(Color online) Function $A_{2}(p^{H}_{t}, \eta^{H})$ defined in (11) as a function of $\Lambda$ (filled circles) and $\overline{\Lambda}$ (open squares) transverse momentum (top) and pseudorapidity (bottom). The deviation of this function from zero defines the contribution to the observable (3) from $P^{(2)}_{H} (p^{H}_{t}, \eta^{H})$ in the expansion (6).