Search for the rare decay of $\psi (3686)\to {\mathrm{\Lambda }}_c^{+}\bar{p}{e}^{+}{e}^{-}+c\mathrm{.}c\mathrm{.}$ at BESIII

Based on a data sample of $(448.1\pm 2.9)\times {10}^6\psi (3686)$ decays collected with the BESIII experiment, a search for the flavor changing neutral current transition $\psi(3686)\rightarrow \Lambda_c^+ \overline{p} e^+ e^- + c.c.$ is performed for the first time. No signal candidates are observed and the upper limit on the branching fraction of $\psi(3686)\rightarrow \Lambda_c^+ \overline{p} e^+ e^-$isdeterminedtobe$1.7\times10^{-6}$ at the 90% confidence level. The result is consistent with expectations from the Standard Model, and no evidence for new physics is found.