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Left panel: raw $p_{\rm T,ee}$-differential yield ($S$) in peripheral (70--90\%) Pb--Pb collisions at \fivenn for $0.7 \leq \mee < 1.1$~\GeVmass overlaid with the opposite charge-sign distribution ($OS$) and the same charge-sign spectrum multiplied by the acceptance correction factor $R_{\rm acc}$ ($B$). Right panel: signal over background as a function of \ptee in peripheral (70--90\%) Pb--Pb collisions at \fivenn for $0.7 \leq \mee < 1.1$~\GeVmass.
Left panel: raw $p_{\rm T,ee}$-differential yield ($S$) in peripheral (70--90\%) Pb--Pb collisions at \fivenn for $0.7 \leq \mee < 1.1$~\GeVmass overlaid with the opposite charge-sign distribution ($OS$) and the same charge-sign spectrum multiplied by the acceptance correction factor $R_{\rm acc}$ ($B$). Right panel: signal over background as a function of \ptee in peripheral (70--90\%) Pb--Pb collisions at \fivenn for $0.7 \leq \mee < 1.1$~\GeVmass.
Dielectron $m_{\rm ee}$-differential yields in semi-peripheral (50--70\%) and peripheral (70--90\%) Pb--Pb collisions at \fivenn, compared with the expected e$^{+}$e$^{-}$ contributions from known hadronic decays. The error bars and boxes represent the statistical and systematic uncertainties of the data, respectively, whereas the bands show the uncertainties of the hadronic cocktail. Arrows indicate upper limits at 90\% confidence level.
Excess dielectron $m_{\rm ee}$-differential yields after subtraction of the cocktail of known hadronic decay contributions in semi-peripheral (left) and peripheral (right) Pb--Pb collisions at \fivenn, compared with calculations for coherent two-photon production of \ee pairs folded with the detector resolution\,\cite{Zha:2018tlq,Brandenburg:2021lnj,Klusek-Gawenda:2020eja,Klein:2016yzr,Klein:2018cjh}. For details see the text. The error bars and boxes represent the statistical and systematic uncertainties of the data, respectively. Arrows indicate upper limits at 90\% confidence level.
Excess dielectron $m_{\rm ee}$-differential yields after subtraction of the cocktail of known hadronic decay contributions in semi-peripheral (left) and peripheral (right) Pb--Pb collisions at \fivenn, compared with calculations for coherent two-photon production of \ee pairs folded with the detector resolution\,\cite{Zha:2018tlq,Brandenburg:2021lnj,Klusek-Gawenda:2020eja,Klein:2016yzr,Klein:2018cjh}. For details see the text. The error bars and boxes represent the statistical and systematic uncertainties of the data, respectively. Arrows indicate upper limits at 90\% confidence level.
Dielectron $p_{\rm T,ee}$-differential yields in peripheral (70--90\%) Pb--Pb collisions at \fivenn for three different \mee ranges, i.e.\ 0.4~$\leq$~\mee~$<$~0.7~\GeVmass (left), 0.7~$\leq$~\mee~$<$~1.1~\GeVmass (middle), and 1.1~$\leq$~\mee~$<$~2.7~\GeVmass (right), compared with the expected \ee contributions from known hadronic decays and calculations for coherent two-photon production of dielectrons folded with the detector resolution\,\cite{Zha:2018tlq,Brandenburg:2021lnj, Klusek-Gawenda:2020eja,Klein:2016yzr,Klein:2018cjh}. For details see the text. The error bars and boxes represent the statistical and systematic uncertainties of the data, respectively, whereas the bands show the uncertainties of the hadronic cocktail. Arrows indicate upper limits at 90\% confidence level.
Dielectron $p_{\rm T,ee}$-differential yields in peripheral (70--90\%) Pb--Pb collisions at \fivenn for three different \mee ranges, i.e.\ 0.4~$\leq$~\mee~$<$~0.7~\GeVmass (left), 0.7~$\leq$~\mee~$<$~1.1~\GeVmass (middle), and 1.1~$\leq$~\mee~$<$~2.7~\GeVmass (right), compared with the expected \ee contributions from known hadronic decays and calculations for coherent two-photon production of dielectrons folded with the detector resolution\,\cite{Zha:2018tlq,Brandenburg:2021lnj, Klusek-Gawenda:2020eja,Klein:2016yzr,Klein:2018cjh}. For details see the text. The error bars and boxes represent the statistical and systematic uncertainties of the data, respectively, whereas the bands show the uncertainties of the hadronic cocktail. Arrows indicate upper limits at 90\% confidence level.
Dielectron $p_{\rm T,ee}$-differential yields in peripheral (70--90\%) Pb--Pb collisions at \fivenn for three different \mee ranges, i.e.\ 0.4~$\leq$~\mee~$<$~0.7~\GeVmass (left), 0.7~$\leq$~\mee~$<$~1.1~\GeVmass (middle), and 1.1~$\leq$~\mee~$<$~2.7~\GeVmass (right), compared with the expected \ee contributions from known hadronic decays and calculations for coherent two-photon production of dielectrons folded with the detector resolution\,\cite{Zha:2018tlq,Brandenburg:2021lnj, Klusek-Gawenda:2020eja,Klein:2016yzr,Klein:2018cjh}. For details see the text. The error bars and boxes represent the statistical and systematic uncertainties of the data, respectively, whereas the bands show the uncertainties of the hadronic cocktail. Arrows indicate upper limits at 90\% confidence level.
Left: Excess dielectron $p_{\rm T,ee}^{\rm 2}$-differential yields after subtraction of the cocktail of known hadronic decay contributions in peripheral (70--90\%) Pb--Pb collisions at \fivenn for different \mee ranges, i.e.\ 0.4~$\leq$~\mee~$<$~0.7~\GeVmass, 0.7~$\leq$~\mee~$<$~1.1~\GeVmass and 1.1~$\leq$~\mee~$<$~2.7~\GeVmass, compared with calculations for coherent photon--photon production of dielectrons folded with the detector resolution\,\cite{Zha:2018tlq,Brandenburg:2021lnj,Klusek-Gawenda:2020eja,Klein:2016yzr,Klein:2018cjh}. Right: Excess dielectron $p_{\rm T,ee}^{\rm 2}$-differential yields after subtraction of the cocktail of known hadronic decay contributions in peripheral Pb--Pb (70--90\%), Au--Au (60--80\%) and U--U (60--80\%) collisions at $\sqrt{s_{\rm NN}}$ $=$ 5.02, 0.2 and 0.193\,TeV\,\cite{STAR:2018ldd}, respectively, in a similar \mee range. The error bars and boxes represent the statistical and systematic uncertainties of the data, respectively. Arrows indicate upper limits at 90\% confidence level.
Left: Excess dielectron $p_{\rm T,ee}^{\rm 2}$-differential yields after subtraction of the cocktail of known hadronic decay contributions in peripheral (70--90\%) Pb--Pb collisions at \fivenn for different \mee ranges, i.e.\ 0.4~$\leq$~\mee~$<$~0.7~\GeVmass, 0.7~$\leq$~\mee~$<$~1.1~\GeVmass and 1.1~$\leq$~\mee~$<$~2.7~\GeVmass, compared with calculations for coherent photon--photon production of dielectrons folded with the detector resolution\,\cite{Zha:2018tlq,Brandenburg:2021lnj,Klusek-Gawenda:2020eja,Klein:2016yzr,Klein:2018cjh}. Right: Excess dielectron $p_{\rm T,ee}^{\rm 2}$-differential yields after subtraction of the cocktail of known hadronic decay contributions in peripheral Pb--Pb (70--90\%), Au--Au (60--80\%) and U--U (60--80\%) collisions at $\sqrt{s_{\rm NN}}$ $=$ 5.02, 0.2 and 0.193\,TeV\,\cite{STAR:2018ldd}, respectively, in a similar \mee range. The error bars and boxes represent the statistical and systematic uncertainties of the data, respectively. Arrows indicate upper limits at 90\% confidence level.