The $\varphi (1020)\to e^{+}{e}^{-}$ meson decay measured with the STAR experiment in Au+Au collisions at $\sqrt{s_{{}_{NN}}}$ = 200 GeV

We report the measurement of the leptonic ($e^{+}{e}^{-}$) decay channel of the $\varphi$(1020) meson in Au+Au collisions at $\sqrt{s_{{}_{NN}}}$ = 200 GeV by the STAR experiment. The transverse momentum ($p_{\mathrm{T}}$) spectrum is measured for 0.1 $\le p_{\mathrm{T}}\le 2.5$ GeV/$c$ at mid-rapidity ($\mathrm{\mid }y\mathrm{\mid }\le 1$). We obtain the $p_{\mathrm{T}}$-integrated $\varphi$(1020) mass $M_{\phi}=1017.7\pm0.8 (\rm {stat.}) \pm0.9 (\rm {sys.})$MeV\mathrm{/}$c^{2}$andwidth$\Gamma_{\phi} = 8.0\pm 2.5(\rm {stat.}) \pm 2.3(\rm {sys.}) $\text{MeV/}$c^{2}$, which are within 1.5,$\sigma$ and 1.1,$\sigma$ of the vacuum values, respectively. No significant difference is observed in the measured $p_{\mathrm{T}}$ spectrum, $dN\mathrm{/}dy$, or $<p_{\mathrm{T}}>$ of the $\varphi$(1020) meson between the $e^{+}{e}^{-}$ and hadronic ($K^{+}{K}^{-}$) decay channels as measured by the same experiment. The experimental results are compared to a theoretical model including medium-modified $\varphi$(1020).