Physical Review D, vol.97, no.7, 2018 (SCI-Expanded)
We search for rare decays of D mesons to hadrons accompanied by an electron-positron pair (h(h(′))e+e-), using an e+e- collision sample corresponding to an integrated luminosity of 2.93 fb-1 collected with the BESIII detector at s=3.773 GeV. No significant signals are observed, and the corresponding upper limits on the branching fractions at the 90% confidence level are determined. The sensitivities of the results are at the level of 10-5-10-6, providing a large improvement over previous searches.